Okay , I've just reassembled my crankshaft w\new bearings and put back new pistons\rings on the old con. rods. After all this I cant get the crankshaft to turn again.Ibroke the harmonic balancer bolt off in the crank, tryin to turn the darn thing.This thing's frozen tight. what do I do?Any Ideas would help? anybody????????????

 

Take the mains off and pull it out.

Check your bearing clearances.
Check for contact somewhere like at the bottom of the cylinders.
Check to make sure the con rods are on the crank the right way.

You've done something wrong in assembly and asking us what you did wrong without being able to see the engine is just going to be guesswork.

Were you able to turn the crank before installing the con rods? If so then you did something wrong when you installed the con rods.

[This message has been edited by Stephen 87 IROC (edited July 16, 2002).]

 

A couple of questions. One did you happen to plasti-guage the bearings to see what tolerance you had between the crank and the bearings. For race applications .003" is usually the standard and for street .001-.002 depending on the motor and application. Second did you put any kind of lubricant on the bearings before assembling the motor? Third did you measure the piston skirt to cyl. wall clearance to see if you have the proper clearance per manufactures recomendations?

Oh yea, one more thing if any dirt or debris got onto the bearings before you put it together it could keep it from turning. You have to make absolutly sure everything is CLEAN before assembling the motor.

Just a few things off the top. When I assemblied our 355 we trial fit everything and checked and double checked all the clearances. When building a motor leave nothing up to chance or chance just might kick you in the butt when you least expect it like a rod out the side of the block. Hope this helps.

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Wayne Best
Best Racing
67 rs Camaro

• 355 cu in Chevy
• 12.5:1 compression
• 10.90s @ 120 mph

87 Formula 350 w/388cu.in. motor

www.geocities.com/best_racing

 

OKay guys, thanks for the input.The crank turned before I put in the pistons\con rods.I did not use any plasti-guage to check clearence, maybe I should do that.I used a white grease on all bearings and mating surfaces.Whats the right procedure for aligning the crank.Is it to loosen main caps\ bolts, hammer the crank back and forth and then hammer forward then torque to spec?maybe it was the con.rods I think i put it all back togther right.I think its just out of alignmint.I did manage to get the broken bolt out of the end of the crank today. that was close, so okay are there any more tricks?

Thanks for all the Help.

 

I also vote for backwards conrods.

 

Most don't know it but I was told by an engine builder that you should bolt your mains on to half the torque setting going in an cirlce from the middle going outward. once all of them are torqued to half, lossen and spin the crank and retorque to half. Something about aligning the mains and fitting them. Once you have done that once or twice, before you do the final torqueing, spin the crank and then torque.

Just a thought, You might want to get new bearings thou, you might have squished one to much now.

P.s. many maginginzes talk about this also

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86 Chevrolet Camaro Iroc Z-28 Fully Loaded With T-Tops
Mods;
Spohn SubFrame Connectors, S&W Race Car Chassis 8 point Roll Cage, 1997 SS Aniversary 3.42 POSI Rear End with 12" Rotors and 4 Piston PBR Calipers, Balanced Drive shaft... Others soon to come...

Best times before any mods done, Complety Stock;15.6 @ 87mph
Waiting for the tracks to open again to see what I got going on Now!

ntimad8.cz28.com

 

Well Ok I freed the cranshaft up,I removed pistons 5-8 and checked everything and cleaned things again and replaced pistons 1 at a time.Rotating as I went,after the last one was back in I torqued the mains to half,then to full.Then everything spun O.K.I really think some CRUD got between the rod berings on #6,cleaned everything up and it's fine..............Also Put in my Camshaft And Double roller timing set-4deg. REtard.

Thanks for all the help, maybe soon I'll Have it Runnin.. 82 Z-28 350ci

 

Should do the plastic guage.. cheap insurance..

 

Plasti guage, nothing I hope he cleaned the crank oil passages throughly and with high pressure air, or it will freeze up again soon.

Kevin

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86 Chevrolet Camaro Iroc Z-28 Fully Loaded With T-Tops
Mods;
Spohn SubFrame Connectors, S&W Race Car Chassis 8 point Roll Cage, 1997 SS Aniversary 3.42 POSI Rear End with 12" Rotors and 4 Piston PBR Calipers, Balanced Drive shaft... Others soon to come...

Best times before any mods done, Complety Stock;15.6 @ 87mph
Waiting for the tracks to open again to see what I got going on Now!

ntimad8.cz28.com