resistance to rotation, of crank durring short blk assembly

[grumpyvette]

Ok youve just installed your crankshaft in the engine block, with new main bearings and everything's well coated with assembly lube,and oil, and youve torqued down the main caps to spec. in at least three stages, and then gone back and rechecked the studs or bolts per the manufacturers instructions, but you have yet to install the pistons and rods, OK, its time to check the rotational resistance at the first stage.
With the crank shaft alone in the main bearings, any inconsistency in the assembly lube thickness, or journal surface finish could and probably will cause a difference in rotational resistance or drag, if it spins fairly easily with a couple fingers on the crank snout with all the mains torqued down and your plastic-gauge checks and micrometers say the bearing clearances are correct your going to be fine, I generally look to have less than 5 ft lbs resistance , on keeping it rotating, once it starts to move, a properly installed strait crank in a properly honed set of main caps with properly clearances main cap bearings well coated with a 50%/50% mix of assembly lube and marvel mystery oil on the bearing crank surfaces and less than 10 lbs to get it to start rotating as the surface tension of most assembly lubes will resist rotation until it starts to rotate, then the resistance to rotation drops off rapidly

now once you add all the connecting rods, pistons and rings obviously resistance to rotation will increase as rings slide along bore walls and you've added rod bearings, Keeping in mind that we are discussing a short block with no heads installed yet and rings riding on well oiled cylinder walls, that should require less than 40 ft lbs to spin, less than 30 lbs of resistance is ideal, because an engine turns more easily with the heads removed or the spark plugs removed.

[b]a crank bye it self ,sitting in a properly machined block with the bearings in place, having been coated with a decent assembly lube, (I generally mix CRANE CAMS ASSEMBLY LUBE WITH MARVEL MYSTERY OIL IN ABOUT A 50%/50% mix on bearings) and the main caps torqued in place should require no more that 10 ft lbs to start to spin (MAXIMUM) and in most cases noticeably less to keep it spinning, in-fact most are easily spun with finger pressure alone.[/b]
if it takes more than 10 ft lbs somethings either not machined correctly or your clearances or lube are wrong.
after you add the rods and pistons with the rings its resistance to rotation obviously increases but should still be UNDER 40 ft lbs to spin an assembled short block,If your carefully checking clearances you should see a minimal increase in resistance to the crank rotation, during assembly, as each piston assembly is added and torqued into place as ring drag increases resistance but the bearings should add little or any drag if properly sized and lubed.
obviously youll want to check the piston to bore clearance at several locations along the circumference of the bore to piston clearance, and check the blocks cylinder bore for consistent diam. and the bore being truly round in shape and but don,t forget to check the piston ring groove back clearance in the ring grooves and the ring end gaps plus look for piston pin bind in the piston pin bore, look for rod journals that are tapered or out of round and connecting rods with a big end thats not round or bearing that are not consistent in diameter across the bearing bore, but Ive also occasionally seen guys try to install rods without checking side clearance or who failed to get the correct side of the connecting rods facing each other or guys using rod bearings that didn,t have the correct edge bevel to clear the journal s radias edge, usually the narrower clevite (H) series have extra clearance

Get out the torque wrench and with the damper bolt installed turn the crank,and while its yet to have the rods and pistons installed, and its lying in its bearings, IT SHOULD TAKE ABOUT 10-12 ft lbs OR LESS to get it moving, and LESS than 10 lbs to keep it moving.
EVEN IN NEW MAIN BEARINGS, it should REQUIRE EVEN LESS ONCE IT LAPS INTO PLACE WITH THE ASSEMBLY LUBE
IF it takes more force theres a clearance issue or the crank or block needs to be checked carefully for straightness, journal tapper and roundness and surface finish and the bearings need to be checked for clearance and proper installation and crush,remember if it won,t turn or spin easily STOP RIGHT THERE and find out why! don,t forget to check the TRUST BEARING fore and aft movement/CLEARANCE
once youve installed EACH connecting rod, you'll want to do the test again, remember each piston with its rings adds drag, AND YOU NEED TO VERIFY THE RING GAPS AND PISTON GROVE DEPTH AND CLEARANCE TO ALLOW THE RINGS TO SLIDE BACK INTO THE GROOVES, but in a well oiled cylinder,its not going to add a huge increase, in drag, as the rings ride on an oil film that prevents incorrect full surface physical contact, between the ring face and bore walls, and the bore surface will lap into the rings and vice versa during the break-in process.
IVE dunked my piston/ring assembly's in a can of MARVEL MYSTERY OIL just before installation with a ring compressor and have never seen the slightest indication of problems either on ring sealing getting the rings broken in, or on tearing the engines down later for inspections the amounts not that great, ideally each one installed adds a bit of resistance but at no time should the short block take over 40 ft lbs ABSOLUTE MAXIMUM to start it spinning,and LESS than 20 lbs to keep it moving, even with all the rings and pistons installed,yes you need to verify the bearing clearances during assembly and IT SHOULD take between 20lbs-25 lbs to start it spinning if the clearances are correct! and LESS than 20 lbs to keep it moving
IF it takes over 40 ft lbs to get it rotating ,youll need too DISASSEMBLE and FIND OUT WHY!

when you get the crank polished take the time and effort to clean out any cross drill oil feed passages and to very carefully de-burr the passage opening edges, as this is a very commonly overlooked issue, below is what at first looks like a perfectly polished crank, with oil feed passages to the rod bearings, but the deep scratches the oil feed passage openings left in the rod bearing surfaces bare witness, after a single rotation, during a trial assembly show they are HARDLY burr free or ready for use, and obviously he failed to check each rod bearing during the assembly process, and probably ignored , what was very likely un-even or rather excessive resistance to the crank rotation. which should never exceed about 40 ft lbs even with all 8 rod bearings and pistons installed


http://www.automedia.com/Engine_Assembl ... 100901e1/1

http://www.automedia.com/Engine_Assembl ... 100901e2/1

http://www.automedia.com/Engine_Assembl ... 101001e3/1

watch the slide show, read the links, its a fairly well done speed course in the basics

READ THIS LINKED INFO
viewtopic.php?f=69&t=9930
Common assembly clearances

GET THE RING END GAP TOO TIGHT AND WHEN THE RINGS EXPAND WITH ENGINE HEAT THE ENDS TOUCH THE RINGS LOCK IN THE BORE AND THE PISTON LANDS SHEAR OFFGET THE GAP A BIT TOO LARGE AND YOU MIGHT BURN A BIT MORE OIL OR LOOSE SOME COMPRESSION, YOU'LL SEE A CHART LATER IN THE THREAD, BUT GENERALLY YOU'LL WANT .0045-.0065 PER INCH OF BORE DIAM. FOR A RING END GAP


(ALWAYS consult your piston manufacturer for recommended clearances. Many pistons require a tighter bore)

Piston to bore 0.0055 - 0.0065" ( measured at centerline of wrist pin, perpendicular to pin)


Piston ring gap MINIMUM end clearances Top 0.022"
2nd 0.016"
Oil 0.016"

Wrist pin 0.0006 - 0.0008" in piston, 0.0008 - 0.0010" in rod for full floating pin (End play 0.0 - 0.005"

Rod bearings 0.002 - 0.025" , side clearance 0.010 - 0.020"

Main bearings 0.002 - 0.003" , 0.005 - 0.007 crankshaft end play

Piston to head clearance 0.035 MINIMUM including gasket (steel rods), 0.060" MINIMUM aluminum rods

Valve to piston clearance MINIMUM 0.020" exhaust , 0.010" intake NO VALVE FLOAT
Recommended: 0.080 intake, 0.100 Exhaust (steel rods) 0.100 intake, 0.120 Exhaust aluminum rods






most piston compression rings have a dot on the upper surface to indicate the side designed to face the top of the piston

ideally the pressure above the piston gets behind the top compression ring and increases the force holding the ring face to the bore surface, noticabl;y more than the ring tension alone can do.
http://www.enginelabs.com/engine-tech/e ... ng-tension

If you put together a stock 400 Chevy, and put standard tension rings in it, it’s probably going to take about 30 to 35 foot-pounds of torque to turn that shortblock,” Massingill said. “If you put it together with the rings that we utilize [for the Engine Masters Competition], it’s going to take about eight or nine pounds. Can you imagine, at 7,000 or 8,000 rpm, the difference that that is? It can easily be 30-35 horsepower.”
BTW

IVE dunked my piston/ring assembly's in a can of MARVEL MYSTERY OIL just before installation with a ring compressor and have never seen the slightest indication of problems either on ring sealing getting the rings broken in, or on tearing the engines down later for inspections

remember that when you go to re-install the compressed piston rings, and piston in the engine block,bores that dunking the piston in MARVEL MYSTERY OIL , just before, its slid into the ring compressor will coat the rings and bore contact areas enough to prevent many small problems that insufficient lube might case





bearings AND connecting rods have an inner facing side and outer side the inner side facing the matching rod has far less edge clearance because they don,t need the radias that is required for the edge of the crank journals


btw
heres the good assembly lube (I usually add about 10% oil too the assembly lube,to get it easy to smear on surfaces during the assembly process)
http://www.cranecams.com/index.php?show ... l=2&prt=15

Ive generally found the H-series bearings are the best choice
MORE USEFUL INFO

BE 100% SURE that the oil pump bolt or STUD doesn,t protrude past the inner main cap surface , because if it bears on the rear main bearing shell it will almost always result in a quickly failed rear bearing

failure to use the correct stud, bolt or nut or check clearances when mounting an oil pump can cause problems


ONE RATHER COMMON MISTAKE IS USING THE WRONG OIL PUMP STUD OR BOLT TO MOUNT THE OIL PUMP AS IF EITHER EXTENDS THRU THE REAR MAIN CAP IT CAN AND WILL BIND ON THE BEARING AND LOCK OR RESTRICT, SMOOTH ROTATION
http://engineparts.com/techbulletins/CL77-1-205R.pdf

viewtopic.php?f=50&t=1222

http://www.chevyhiperformance.com/tech/ ... index.html

viewtopic.php?f=50&t=10363

http://www.4secondsflat.com/Thrust_bear ... lures.html

http://www.circletrack.com/techarticles ... index.html

http://www.connectingrods.net/connectin ... tretch.php

http://www.circletrack.com/techarticles ... index.html

http://www.circletrack.com/enginetech/1 ... education/

http://engineparts.com/it_bearinginstall.asp

http://www.circletrack.com/enginetech/c ... ce_basics/

http://engineparts.com/it_crankinstall.asp

viewtopic.php?f=53&t=8685&p=30565#p30565

viewtopic.php?f=53&t=247

http://www.youtube.com/user/cpmotors#p/u/3/mPwCsPik7KU

http://www.chevyhiperformance.com/tech/ ... index.html

the CRANE assembly lube is excellent but IVE used this grease mixed with a bit of mobile 1 oil as a substitute on bearings at times with excellent results
advance auto carries some
http://www.grumpysperformance.com/p1171 ... _large.jpg
http://shop.advanceautoparts.com/productdetail.aspx?MfrCode=VLV&MfrPartNumber=632&CategoryCode=3251

if your well lubed short block won,t spin at under 40 ft lbs once assembled even with high drag rings its a HUGE PROBLEM!
you need to use moly assembly lube
pull ALL the pistons and rods and verify the crank alone takes LESS than 15 lbs to spin, if not start checking clearances, once that's done verify the piston side clearances, then ring end gaps, ring to groove clearances in the pistons and the piston pin to piston pin bore side clearances,then remember the rods have an inner and outer facing side, and the bearings do also in most cases, check rod side clearance and thrust bearing clearance, and when your assembling the pistons & rods to the crank rotate the crank after each ones installed to find any unusual increased drag, a slightly bent rod, or the wrong bearings can add a good deal of drag


one factor to keep in mind is that rods typically have a side that rides against its matched companion and a side thats BEVELED for clearance on the crank journals radias EXAMPLE



notice the top rods non-beveled side that faces the matching rod is up, but on the lower rod the the beveled side that faces the crank counter weight is up on the lower rod

notice how one side of the bearing holding section has a radias (left)(GOES TOWARD CRANK COUNTER WEIGHT) but the opposite sides flush (right) (FACES MATCHED ROD)
you really need to read thru these threads
viewtopic.php?f=53&t=1795

viewtopic.php?f=53&t=1138

viewtopic.php?f=53&t=1168

viewtopic.php?f=53&t=247

viewtopic.php?f=50&t=989

viewtopic.php?f=69&t=2645&p=6834#p6834

viewtopic.php?f=50&t=1027

http://www.circletrack.com/howto/1818/index.html

viewtopic.php?f=50&t=55


btw spray the bearing and the crank surfaces, and the plastigage with WD40 before you measure clearances and it won,t tend to stick as much


WATCH THIS VIDEO
NEVER USE A TORQUE WRENCH LIKE A BREAKER BAR TO LOOSEN BOLTS as it TENDS TO QUICKLY DESTROY ITS ACCURACY & consistency

http://www.youtube.com/watch?v=zgwwOJ0B ... r_embedded

viewtopic.php?f=53&t=852&p=1812&hilit=resistance+rotation#p1812

viewtopic.php?f=53&t=2726&hilit=plastigauge

viewtopic.php?f=54&t=10500&p=44355&hilit=bearing+clearances#p44355

viewtopic.php?f=59&t=1390&p=3423&hilit=+precision#p3423

http://www.chevelles.com/forums/showthread.php?t=379622

ONE youve installed the engine in the car, and ASSUMING you've PRE-PRIMED the oil pump and oil runs out of the rockers,if it takes more than 40 ft lbs to get it to turn freely , without the spark plugs installed, or accessory belts on, or the transmission installed, somethings binding or the clearances are wrong, Id start by loosening all the rockers and see if it makes a difference, you would not be the first guy to think everything's adjusted correctly yet have the valves not adjusted correctly

read these threads above

if youve used a quality assembly lube, and have the correct clearances it should require NO MORE than 40 ft lbs of force to start an engine too turn and under 20 ft lbs to keep it spinning, and thats with new rings in a newly honed bore, that effort required should drop rapidly to the point that less than 20 ft lbs are required to spin a short block after its been well oiled and rotated dozens of times.
one factor some new guys over look is that rods and bearings are designed with one side having a bevel that faces the counter weights and a non-bevel edge facing the matched rod



In any application where your tightening a nut on a stud , such as on the outer threaded ends of main cap studs or head bolt studs,or rod bolts, youll want to use a lube on the threads that gives consistent torque reading from your torque wrench indicating the correct bolt or stud TENSION, oil and MOLY assembly lube and various thread sealants do not always do that,the end in the blocks course threads have thread sealant, the fine threads on the outer end require a totally different lubricant


GOOD and VERSITILE



WORKS GREAT BUT LIMITED TO A NARROW BORE RANGE AND EXPENSIVE

http://www.amazon.com/KD-Tools-850-Diam ... 0002STSMG/

this type (ABOVE) handles many applications but the cheap versions are a P.I.T.A. to work with


BTW when you go to buy a ring compressor....this type(ABOVE & BELOW) works far better than the others, but its specific to a very limited range in bore size applications



http://store.summitracing.com/partdetail.asp?autofilter=1&part=PRO%2D66766&N=700+115&autoview=sku

Proform 66766 $31

Tech InformationInstallation Tips


Engine Bearing Installation and Fitting Tips

When measuring bearing measurements, they should always be taken at 90-degrees to the parting line to determine the minimum clearance. If measuring the bearing wall thickness, use a special micrometer with a ball anvil to fit the curvature of the bearing ID. The best way to determine bearing clearance is to measure the bearing ID with the bearings installed in the housing and the bolts torqued to the specified assembly torque. Use a dial bore gauge to measure the bearing ID at 90-degrees to the parting line, then subtract shaft size from bearing ID to determine the clearance. If the dial bore gauge is zeroed at the actual diameter of the crankshaft journal to be installed, the dial bore gauge will then read clearance directly and the subtraction calculation can be eliminated. About .001" clearance per inch of shaft diameter is a good rule of thumb. Increasing that by about .0005" will add a little margin of safety when starting out, especially for rods. Example: .001" X 2.100 = .0021" then add .0005", so starting out set clearance at .0026" for a 2.100 shaft.

If clearance adjustments need to be made, use either an extra clearance part for more clearance or an undersize part for less clearance. It is permissible to mix sizes if less than .001" adjustment in clearance is desired. When mixing sizes for a select fitting: a) never mix parts having more than .0005" difference in wall size; b) and always install the thickest wall shell in the upper position if installing a rod bearing or the lower position if installing a main bearing. When working with a reground shaft, always measure assembled bearing ID's first. Next have a shaft sized to produce the desired clearance since there are no extra clearance parts available for undersize shafts.

When measuring a bearing ID or wall thickness, avoid measuring at the parting line. The diagram illustrates there is a parting line relief machined into nearly all bearing shells. This relief is to allow for any mis-match between upper and lower shells due to tolerance differences, or possibly resulting from cap shift or twist during assembly. To determine bearing wall eccentricity or assembled bearing ID ovality, measure at a point at least 3/8" away from the parting line.

When installing any bearing DO NOT ATTEMPT TO POLISH THE BEARING RUNNING SURFACE WITH ANY TYPE OF ABRASIVE PAD OR PAPER. Bearing overlay layers are extremely soft and thin – typically .0005" on high performance parts. These thin layers can easily be damaged or removed by an abrasive media. Because the overlay layer is electroplated, it may exhibit microscopic plating nodules that make it feel slightly rough. The nodules are the same material as the rest of the plated layer and will quickly be flattened by the shaft. Bearing surfaces can be lightly burnished with solvent and a paper towel if desired.

Arriving at the correct choice of a high performance bearing for any given racing application is much like determining what clearance works best. From past experience, our knowledge of the intended usage and common sense can guide us in making an initial choice. Next, we can fine tune the selection process based on those results. The information given here is intended to aid in the initial selection as well as the fine tuning process.

The following table serves as a brief overview of the features included in each of the special Clevite 77® brand high performance bearing series.


narrow bearings have beveled edges to prevent the edge of the crank journal radias touching the bearing, h series are beveled edge bearings designed for higher loads so they are a bit harder
70-95 454 Chevy Clevite performance main bearing set. Clevite 77 "H" Series bearings have a medium level of eccentricity, high crush, and rod bearings have a hardened steel back and thin overlay. These bearings also have enlarged chamfers for greater carankshaft fillet clearance and are made without flash plating for better seating. Use "H" Series bearings with crankshafts that have oversize fillets and where engines run in medium to high RPM range.

[grumpyvette]

viewtopic.php?f=53&t=509&p=632#p632

youll need ring assembly info also

and never beat the damper onto the crank, use the correct tool


look at the picture carefully
the small 7/16 thread ,on the tool threads into the crank, the damper slips over the tool, the large washer style bearing slips over the tool followed by the solid washer followed by the large nut that threads on the tool, the back of the tool is normally a 9/16 or 5/8 hex this is held with a box end wrench to keep the engine from turning, the large nut is usually a 1 1/8" nut and it is tightened with an open end 1 1/8" wrench or a adjustable wrench against the two washers drawing the damper onto the crank snout! lube the threads on the tool, the inside of the damper and crank snout with oil before starting. the damper will normally slide on about 1/4 of the way bye hand then the tool is needed to draw the damper on the last 3/4 of the distance, don,t over tighten the tool the 7/16" thread will snap off in the crank after the damper bottoms out on the lower timing gear if you do!,
NEVER USE A HAMMER AND BLOCK OF WOOD TO DRIVE THE DAMPER ON, YES THOUSANDS OF GUYS THINK THEY DID IT WITHOUT ANY PROBLEMS BUT...
IT WILL DAMAGE THE THRUST BEARING CLEARANCES,
IT CAN BREAK THE ELASTOMER TORSION RING ON STOCK DAMPERS
IT CAN CAUSE THE INERTIAL RING ON FLUIDAMPER TO BECOME JAMMED INTERNALLY
IT CAN CAUSE THE DAMPER TO FAIL.
IF THE DAMPER FAILS THE CRANK WILL EVENTUALLY BE DAMMAGED
IT GREATLY STRESSES THE CRANK SHAFT
IT CAN DAMAGE THE CRANKS TRANSMISSION PILOT BEARING
IT CAN DAMAGE THE TRANSNSMISSION
ALMOST EVERY TYPE OF DAMAGE IS NOT SOMETHING THAT SHOWS UP RIGHT AWAY, BUT IT WILL DAMAGE THE PARTS LISTED AND THERES THOUSANDS OF GUYS THAT ARE WONDERING WHY THOSE PARTS FAILED 6-24 MONTHs LATER WITH NO CLUE AS TO THE CAUSE!
[b]ASK YOURSELF THIS QUESTION, IF CRANKSHAFTS THAT ARE A FEW THOUSANDS OUT OF LINE I.E. NOT PERFECTLY STRAIT ARE BENT/STRAITEN WITH A LEAD HAMMER BY CRANK MANUFACTURES (and yes thats how its done) AND CRANKS THAT ARE DROPPED ON A CONCRETE FLoOR SOMETIMES BEND SLIGHTLY ,(happens all the time) WHAT MAKES YOU THINK THAT BEATING ON THEM WITH A HAMMER AND A BLOCK OF WOOD WONT DAMAGE THEM? AND WHILE WERE AT IT WHAT WOULD YOU DO TO SOME GUY YOU CAUGHT BEATING ON YOUR ENGINE BLOCK WITH A HAMMER? WELL WHAT DO YOU THINK THE CRANKS DOING TO YOUR MAIN CAPS WHEN YOU BEAT ON THE CRANK? PROPERLY USED THAT INSTALLATION TOOL CAN EXERT OVER 15 TONS OF PRESSURE TO SLIDE THE DAMPER ON, IF IT WONT SLIDE ON, THERES A PROBLEM! FIND IT AND FIX IT .....DON,T BEAT ON THE DAMPER/CRANK

having a few tools designed to easily rotate the engine on hand helps
crank rotators


flywheel turning tools


http://www.jegs.com/i/JEGS/555/80743/10002/-1

http://www.jegs.com/webapp/wcs/stores/servlet/KeywordSearchCmd?storeId=10001&catalogId=10002&langId=-1&Ntk=all&Jnar=0&itemPerPage=90&Ne=1%2B2%2B3%2B13%2B1147708&searchTerm=55580530

[grumpyvette]

check your cranks end play (forward/aft slack in the bearings)

http://members.rennlist.com/v1uhoh/cranksha.htm

http://www.tpub.com/content/constructio ... 050_74.htm

http://www.chevyhiperformance.com/tech/ ... index.html

http://books.google.com/books?id=TXEMMg ... &ct=result

http://www.circletrack.com/howto/1815_c ... index.html

http://books.google.com/books?id=1dcXtE ... &ct=result




HERES A GREAT DEAL OF INTERESTING RELATED INFO

viewtopic.php?f=53&t=619&p=10925&hilit=bearings#p10925

viewtopic.php?f=54&t=3519&hilit=bearings

viewtopic.php?f=54&t=3834&p=10199&hilit=bearings#p10199

viewtopic.php?f=53&t=3449&p=9293&hilit=bearings#p9293

viewtopic.php?f=54&t=2187&p=9097&hilit=bearings#p9097

viewtopic.php?f=53&t=247&p=8348&hilit=bearings#p8348

viewtopic.php?f=51&t=1479&p=7446&hilit=bearings#p7446

viewtopic.php?f=53&t=2727&p=7078&hilit=bearings#p7078

viewtopic.php?f=53&t=2351&p=6453&hilit=bearings#p6453

viewtopic.php?f=53&t=88&p=5709&hilit=bearings#p5709



http://www.summitracing.com/parts/CRN-99004-1/




ABOVE FOR BOLT THREADS NOT BEARINGS





ABOVE FOR BEARINGS, LIFTERS CAM LOBES ETC.
read these links

http://www.summitracing.com/parts/MAN-40177/?rtype=10

http://www.performanceproducts4benz.com ... -lube.html

viewtopic.php?f=53&t=3449&p=9133#p9133

viewtopic.php?f=54&t=2187

viewtopic.php?f=54&t=2725&p=7076&hilit=studs+sealant#p7076

viewtopic.php?f=44&t=805&p=1171&hilit=studs+sealant#p1171

viewtopic.php?f=53&t=247

viewtopic.php?f=53&t=852

viewtopic.php?f=53&t=3897

viewtopic.php?f=53&t=5478

viewtopic.php?f=53&t=509

viewtopic.php?f=53&t=4419

viewtopic.php?f=51&t=1479

viewtopic.php?f=51&t=2919

[grumpyvette]

sometimes IM absolutely amazed at the way obvious indication thats somethings very wrong with an engine during the assembly process are being ignored by guys that seem to be clueless to the obvious indications that theres a serious problem.
I get a call from a friend who has a 455 Pontiac, on his engine stand in his garage, its his first engine build, that hes in the process of assembling, and btw this doesn,t just apply to Pontiac engines,he got the block back from the machine shop and has a new crank shaft, he drops the bearings in place coats them with assembly lube, drops the crank into the bearings and installs the main caps , after torquing the main caps, to the listed specs ,he finds it took over 80 ft lbs to get the crank to rotate, in the bearings.
bearings do come in different sizes and crank journals can obviously be cut and polished to different sizes, and its not unusually for a crank to have some or all journals, measure slightly different that the manufacturers intended diam. so measuring and checking each bearing clearance and journal is mandatory,..that resistance to easy rotation, should have been a huge flashing red light signal, with sirens blaring, that something was terribly wrong, a crank with no connecting rods installed should spin freely with minimal finger pressure.
yet his lack of experience and his thinking that the machine shop must have checked all this out before they gave him the components had him thinking that this condition must be normal, he was about to install the connecting rods and pistons but luckily thought to call and ask questions.
the resulting checks showed he had installed a standard crank with .0010 oversize bearings and never used any plasti-gauge or bothered to measure.
If he had continued he would surely have had a engine come apart withing minutes of starting as the main bearings were totally ruined. as it was he needed to replace the main bearings and polish the crank, checking the block amazingly indicated it was not warped or in need of re machining.... we ALL make mistakes its part of the learning process, but at the first indication something seems to be not correct STOP ASK QUESTIONS
IF your ever unsure STOP and ask questions before you proceed, NEVER assume ,ALWAYS do research before you guess! and it sure helps to have experienced friends so join the local ho rod clubs, yes 70%-90% of the guys will be clueless or unwilling to help, but theres usually at least one experienced old geezer who is willing to teach new guys, if your willing to supply lunch or a few beers during the process




Common assembly clearances

(ALWAYS consult your piston manufacturer for recommended clearances. Many pistons require a tighter bore)

Piston to bore 0.0055 - 0.0065" ( measured at centerline of wrist pin, perpendicular to pin)


Piston ring gap MINIMUM end clearances Top 0.022"
2nd 0.016"
Oil 0.016"

Wrist pin 0.0006 - 0.0008" in piston, 0.0008 - 0.0010" in rod for full floating pin (End play 0.0 - 0.005"

Rod bearings 0.002 - 0.025" , side clearance 0.010 - 0.020"

Main bearings 0.002 - 0.003" , 0.005 - 0.007 crankshaft end play

Piston to head clearance 0.035 MINIMUM including gasket (steel rods), 0.060" MINIMUM aluminum rods

Valve to piston clearance MINIMUM 0.020" exhaust , 0.010" intake NO VALVE FLOAT
Recommended: 0.080 intake, 0.100 Exhaust (steel rods) 0.100 intake, 0.120 Exhaust aluminum rods
related info
viewtopic.php?f=44&t=4125&p=16379&hilit=pontiac+related#p16379

viewtopic.php?f=53&t=5933&p=18274&hilit=cam+degree+tools#p18274

http://www.chevelles.com/forums/showthread.php?t=379622

http://boxwrench.net/specs/pont_265-455.htm

viewtopic.php?f=53&t=2726

viewtopic.php?f=59&t=1390&p=3423&hilit=precision#p3423

http://vintage.mitchell1.com/PClubData/ ... 745121.pdf

http://www.amazon.com/How-Build-Perform ... 1884089674

http://www.mre-books.com/pontiac/engines.html

http://www.highperformancepontiac.com/t ... index.html

http://www.highperformancepontiac.com/t ... index.html

btw these are not all that bad as an engine stands, he purchased it from northern tool, I can,t see how anyone who is serious about building engine does it without at lease a reasonably strong/ stable engine stand
http://www.northerntool.com/shop/tools/ ... _200442439

[elisalvador]

hy grumpy im building a pontiac 400 , engine has a rope seal , in stalled the crank and rods/pistons and i know the rope seal adds more drag, the amount of pounds needed to get crank moving is 39 lbs and to keep it rotating is 30 lbs. is this normal,,,,, is it ok for a rope seal ????,,, i know its a little on the high side according to your specs...thanks

[grumpyvette]

OK Im assuming your measuring the crank resistance without any rods attached here. correct?
if the rope rear seal was liberally coated with moly assembly lube the crank alone should require a good deal LESS torque to allow it to spin , like 15-20 lbs max, so,Id first try whacking the cranks rear flange in all directions with a large rubber mallet several times at about every 45 degrees around the clock, going around at least 5 full times to fully seat the seal on the rear main journal. as that won,t require any dis-assembly.
if after removing the rear main cap you find its only the rear main rope seal causing the extra drag id suggest trimming it and reinstalling it and try for a 20 lb drag, if its a bit higher it will work, but that's not ideal, still it will wear in, during engine operation so its not going to stop the assembly provided thats determined to be the source of your resistance to rotation.
if it drops to 15-20 lbs you good to continue, with further assembly, if not,STOP! pull the rear main cap and lower seal on the block and check the resistance to rotation, it should drop to that 15 lbs, if not you have other issues, if after removing the rear main cap you find its only the rear main rope seal causing the extra drag id suggest trimming it and reinstalling it and try for a 20 lb drag, if its a bit higher it will work, but that's not ideal, still it will wear in, during engine operation so its not going to stop the assembly provided thats determined to be the source of your resistance to rotation., did you use plasti-gauge on the bearings to verify clearances? did you coat all the bearings with assembly lube during final assembly?
are you sure all the main caps are on the correct journals with the caps facing the correct direction and are all the bearings seated correctly?
have you checked to see if the journal edges and bevel on the bearings are touching, or binding?
you might simply need to trim the rope seal a bit and reinstall it , but I sure would figure out why your having that much resistance before continuing the build, if thats the crank alone in the block that takes 30 plus ft lbs to keep spinning. with the rear main lower cap removed you better start checking to locate the reason ,
now if you remove that lower rear main cap and don,t see a noticeable drop in resistance Id sure look at the thrust bearing clearance and other bearing clearances ? ? ?
the difference between assembling an engine correctly and just bolting parts together is recognizing that each step in the process will result in clues to its correct or faulty assembly, and having the smarts to ask questions and stop and correct anything that you find that might be a problem or indication that some parts not fitted correctly and as you gain experience youll find ignoring obvious signs of potential problems almost always comes back to bite you in the ass later.
and yes I learned that the same way 99% of us did, by screwing up my first few engine builds in some ways, now that doesn,t mean those engines didn,t run, but it sure means that they didn,t run to nearly their full potential or last as long as I expected or in some other way taught me that stopping and asking questions before proceeding was far preferable too the results youll get assuming that
the USE A BIGGER HAMMER!
AND
plunge FORWARD REGARDLESS!
APPROACH DOES WORK!
BECAUSE with experience youll find they RARELY DO!



http://www.wallaceracing.com/torque-engine-specs.html

VERIFY THE EDGE OF THE MAIN CAP BEARINGS IS NOT BINDING ON THE JOURNAL SIDE BEVEL RADIAS (BLUE /GREEN AREAS)


VERIFY THE MAIN CAPS FACE THE CORRECT DIRECTION AND ARE IN THE CORRECT LOCATION, SEATED CORRECTLY AND TORQUED IN STAGES TO CORRECT TORQUE, BEARING TABS IN CORRECT PLACE








rope rear main seals can be used and they work reasonably well, but there are vitron seals available that tend to last longer and seal better
obviously you first need access to the rear main seal, and its a whole lot easier if the engines out of the car, on an engine stand , during the instal process, but in any case youll remove the old rear main seal, carefully clean and degrease the area in the block and main cap where the seal you selected to use is installed.
if your using the vitron/rubber style rear main seal , the process duplicated the chevy rear seal info posted earlier,the surface facing the block or cap is lightly coated with a good flexible sealant, the seal installed with the flexible lip facing the front of the block, the ends of each seal get a dab of silicone sealant and a bit of MOLY grease on the inner surface the crank journal rests against, once the caps installed, hot oil from the running engine expands the rope seal, in theory sealing the rear main, in most cases it does a decent job.

if your using a rope/graphite seal the groove in the block and main caps carefully cleaned and degreased with brake cleaner and a brush. IF access is available ,the rope seals placed in the groove,with a bead of silicone on the outer edge facing the bottom of the groove in both the block and rear main cap , and its forced into the groove by rolling a large socket over its inner surface, compressing it into the groove,and a razors used on the ends to cut them flush then a dab of silicone applied to each end of the seal where they mate, the seal expands when soaked with hot oil from the running engine, the moly grease tends to prevent wear until the rope seal absorbs oil, in theory applying a low pressure contact seal, that prevents oil leaks.....the vitron seals tend to work a bit better.

the pictures below show a filthy block that needs to be cleaned and the guy trying to install obviously the larger and longer rear main seal from the larger crank diameter that must be cut and modified to fit but the process is nearly identical


Kit says to use a smooth cylindrical object to pack seal in groove. big deep-socket worked fine.




the rope seal below looks correctly seated but it must be coated with a mix of oil and moly assembly lube before the cranks installed






http://www.ehow.co.uk/how_8000662_insta ... ntiac.html
http://www.jbp-pontiac.com/products/gas ... seals.html


http://www.tinindianperformance.com/Pon ... 0Seals.htm

http://www.allpontiac.com/rearmain_seal.html

http://www.bopengineering.com/viton_compare.shtml

http://www.bopengineering.com/seal_instructions.pdf

Which Pontiac rear main seal do I need?
At Tin Indian Performance, we sell / advertise our seals according to the main journal size of the appropriate engine that uses them.



Pontiac engines / blocks that have 3 inch mains are 326 / 350 / 389 / 400. Keep in mind that when I say this, it means the cid of the original block casting. Pontiac engines / blocks that have 3.25 inch mains are the 428 and 455 blocks. The most common main journal size for aftermarket blocks is 3"; however, 3.25" mains are also available as well. Now for those who are into measuring things and have the crankshaft available to them, the 3 inch main blocks have a crank sealing surface of approximately 3.188 inches. This would require the TIP-RM300 seal The 3.25 inch main bearing cranks have a sealing surface of 3.436 which would use the TIP-RM325.

So when ordering your seal, know what main bearing journal size you have.
If it is a 3" main you will need a TIP-RM300.
If it's a 3.25" rear main journal, then it is a TIP-RM325.

[87vette81big]

Try repacking the Rear Main Rope Seal tighter Elsalvidor .
They do have considerable drag compared to a rubber seal. Till the engine fires & spins 50-100 Revolutions around.
Rope Seal burnishes in.
No perfect rear main seal made for a Pontiac except for Original NOS GM ASBESTOS Fiber Rope Seal.
Best made ever. Almost unobtainable.
EPA to blame why gone forever.

Rubber Viton works best in Indian Adventure Aftermarket $5-6k Race block & with Billet Crower crankshaft.

You can always remove Crankshaft, remove upper seal half. Lower cap seal.
Install crank.Torque main caps down to specs.
Recheck. Will be 5-10 Ft/lbs. If clearances correct.
Pontiac Factory cranks are super tangle line straight. Crankpin index near perfect. Unless crankshaft grinder goofed up.

The original GM Asbestos Fiber Rope Rear Main seal NOS in box worth up to $400 - $500 to Pontiac Die Hards like me.
They worked that good.
Makes a Viton look Meak....They will drip some oil no matter whats tried.

Original GM Will Not.

[elisalvador]

thanks guys . the crank and pistons and rods are installed ,, and it takes 39 lbs to get it started and it drops to 30 lbs to keep it rotating,,, im assuming this is ok ?? its a little on the high side ,,,, i also measured it with just the crank and it took 19 lbs to get it moving and 10 lbs to keep it rotating .....thanks again

[grumpyvette]

thanks guys . the crank and pistons and rods are installed ,, and it takes 39 lbs to get it started and it drops to 30 lbs to keep it rotating,,, im assuming this is ok ?? its a little on the high side ,,,, i also measured it with just the crank and it took 19 lbs to get it moving and 10 lbs to keep it rotating .....thanks again

that sounds reasonable for a newly assembled Pontiac short block

[elisalvador]

thanks again guys

[grumpyvette]

Doing a cam swap and took a pic inside the cam bearing hole and saw this pictured below, is this normal?

HERES THE PICTURE HE POSTED WITH A COMMENT, ADDED!



any time you find some sign of wear on an engine,part, or indications of parts contacting each other ,where you think they might be a problem,
STOP! look it over and ask questions, before you proceed.
Look closely at the first picture,look thru the cam bearings at the second, third block web ares also, it looks like several counter weights are contacting the block as they rotate, IF it was my engine Id check the trust bearing clearance, and if I found significant wear, replace the cam bearings and the mains and rod bearings, IF YOU find significant wear on the THRUST bearing clearance check, simply because that bearing material went some place and the cam bearing look like they are well worn.

[87vette81big]

Will require a new crankshaft likely.
Thrust surface will measure .030"-.060" wear.

[grumpyvette]

and YES, as pointed out by BRIAN, you might find the crankshaft thrust bearing surface so worn, it needs to be welded and re-machined or a new replacement crank installed>

[87vette81big]

The Scat 9000 Series crankshaft is what I used in my 1994 GMC Suburban.
Special Alloy Iron Crank. 1-piece rear main seal.
$199.99 from Summit. Free shipping.
All New.
Micro polushed & chamfered oil feed holes.
Micrometer checked + - .0002" from GM Blueprint specs.
Not Crower or BRC Billet quality tolerance but still excellent for $200.00.
UDA made.
9000 CRANK Prebalanced to GM SPECS. + - 40 grams is Factory Tolerance.
Scat balances to + - 1 gram middle of Road STOCK GM BOB WIEGHT.
I installed as is . No machine shop balance.
15,000 miles later no ussues.
80 pdi cold oul pressure.
65-70 psi hot.
Idle 45 psi hot.
Vandervell half grooved main bearing set.
Vandervell rod bearings.
Melling M55A 1967-70 Z28 oil pump.
Ran Suburban hard today driving throygh 2-3 foot snow drifts.

[87vette81big]

Its a pretty good day after all Grumpy.
The Fed Ex guy dropped a small package.
I purchased a NOS FELPRO Pontiac Rear Main Seal.
The original Felpro Logo from 1970's shown on Fleabay.
Just $10 bucks.
Package shows application 1959-70 Pontiavc 389 &400.
Poncho 400 was made till 1979.
So this Rope Rear Main seal was made in late 1969-70 year.
43 years old. Still nice. No Rot.
Its 100% Asbestos center core like Pontiac used original 1955-79.
Take photos later & post.