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Author Topic:   crank turns hard by hand at one spot !!!!!!!
pbrcowboy2
unregistered
posted October 19, 2003 06:02 PM           
alot of you more experienced racers on here have provided us with more knowledge then i can even tell of!!! thank you for all your guy's help!!! Thank you once again!!!!

Here's the newest question guys!! my heads are off my oil pan is off and my camshaft is out but why is it when i turn my crank over by hand it spins all right but when it gets to one point it gets real tight and stiff like its locked up or something?
Would love any feedback from you guys!!


BK19
Member
posted October 19, 2003 07:57 PM
it could be one of the main caps are mixed up or bearing clearances to tight


racer17j
Member
posted October 19, 2003 10:56 PM
yup check the clearences turn it to where it startes to get stiff and check the ones that are at tdc and bdc thats where your bind will more than likely be


dean_7585
Member
posted October 22, 2003 06:22 AM
Is just the crank in or do you have the rods in too ?? When I built mine I had a tough spot and it ended up being the rod bolts hitting the cam.


rico 08
Member
posted October 22, 2003 07:31 AM
If there's a rod on backwards the small end will hit the counterweight of the crank,also a bent rod will do the same.


tilley88
Member
posted October 22, 2003 08:28 AM
Sounds like a wrist pin seizin.


pbrcowboy2
unregistered
posted October 22, 2003 04:20 PM           
we took the oil pan off and found out we have a racin crank turned .020 the rods are on!! and we have 380 dome pistons. how does the rod bolts hit the cam? we are gonna take off the caps and replace the bearings. yall think we should keep the high volume oil pump or put a stock pump in there?


rico 08
Member
posted October 22, 2003 05:51 PM
Take all the main caps off and buy/borrow a dial indicator,spin the crank with the dial on the journals,look for any runout,especially on the center main(bent crank)also get some plastigauge and check your clearances.I always run a stock volume pump.


Sidebite252
Member
posted October 28, 2003 08:13 PM
We do the same as Rico 08 - checking the runout on the crank. Anything over .003 is probably looking for trouble. .0015 to .002 is preferred. Also - our own experience - Beg, borrow, or steal a micrometer and I.D. gauge and check the clearance this way. We've been bitten by using plastagauge and have thrown it out of the shop. Bent crank could be your problem but that's just one place to look.


ChityBang2
Member
posted November 07, 2003 02:35 PM
CHECK YOUR LINE BORE.OR BENT CRANK


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