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Discussion Starter #1
I bought a 540 Dart shortblock and today I have been disassebling and double checking everything.

It's a good thing I did, but before I bag on anyone, I'm going to give him the opportunity to make it right.

I have a question about crankshaft endplay...

All I've read says BBC needs .006-.010

I have maybe .001 !! Do they make bearings with say .005 smaller shoulder or what do I do?

Jeff
 

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Use some 600 grit paper on a piece of glass. Use WD 40 and wet sand the sides of the thrust bearing until you get your clearance. I set my 598" NA BBC at .007.
 

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steelcomp was here
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Hold On There...

Before you start sanding on anything, loosen the rear main and move the crank front to rear and see what you get. Make sure the rear cap and block aren't shifted slightly taking up that few extra thou you need. Tighten one of the other main caps to pry against and use a small prybar or screwdriver and move the crank fore and aft with some reasonable force. Once you've done this, then tighten the rear main and re-check. It's uncomon to have so little thrust clearance.
 

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Before you start sanding on anything, loosen the rear main and move the crank front to rear and see what you get. Make sure the rear cap and block aren't shifted slightly taking up that few extra thou you need. Tighten one of the other main caps to pry against and use a small prybar or screwdriver and move the crank fore and aft with some reasonable force. Once you've done this, then tighten the rear main and re-check. It's uncomon to have so little thrust clearance.
Steel comp is right. Take the rear main upper off (rearmain cap ) and try again. Core shift and other things will make this happen.Also I would spin the crank with the rear saddle off and see if it is smooth. Retorque and try again. Don't go setting clearances on a one shot attempt. IMO M
 

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Discussion Starter #7
Alright - I loosened the rear main cap and then gently wedged a screwsriver so that I was holding the crank forward and re-torqued the rear main.

Now I can get about .0045 by using reasonable force with a screwdriver.

Still too tight?
 

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steelcomp was here
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.0045 is on the tight side, but I think it's OK. I usually shoot for .0050 min, but I've heard others say less.
 

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Discussion Starter #9
I just spun the crank around and it takes much less force to rotate it now. You guys were right about core shift on the main cap.

After spinning it around a bit I can get .006 out of it now.

I think I'm good....

Thanks guys!
 

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I just spun the crank around and it takes much less force to rotate it now. You guys were right about core shift on the main cap.

After spinning it around a bit I can get .006 out of it now.

I think I'm good....

Thanks guys!
Hey clutch, Retorque and try again. IMO M
 

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FYI thrust bearings are only made thicker in case of a burned up crank.,A crank grinder will weld it back up and fit it to that bearing.
 

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Dart blocks have no locating pins, etc for the rear cap. So...the rear cap could go on anywhere back and forth wise. The guys have you on the right track, prying forward on the crank, then tightening/ torquing the rear main.
Wags
 

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Resident Ford Nut
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I just spun the crank around and it takes much less force to rotate it now. You guys were right about core shift on the main cap.

After spinning it around a bit I can get .006 out of it now.

I think I'm good....

Thanks guys!
I'm sure you could have got the same info on Hot Boat :p

Sleeper CP :D
 

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.004 times the bore size top ring .0045 to .005 2nd ring.Speed pro ring says now to open the 2nd up a bit more releaves any pressure between rings.Most ring packages will have instructions for gaps, for NOS ,blower ,turbo,NA,the more boost the wider gap.Get some childs and albert zg rings,there expensive but really good,overlapping 2nd ring,I prefer those over total seals style 2nd ring.
 

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Village Idiot
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Uh, oh..another can of worms. LOL
Wags
Ask what they should be. Ask whether the second ring gap should be looser or tighter than the first. That ought to start something. Oh, then ask about zero gap rings. LOL
Wags
We have already been through this one before haven't we?:D

Paul
 

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I've always done it by snugging the rear main, tapping the crank from the rear, then from the front and then torque the main. Always worked for me.

Tim
It is funny, I use this method with a rubber mallet, while my brother uses the screwdriver method. Both work. We have had to sand the bearings a few times to get the clearances we want as we run converters in our cars, but you have to check it one of these ways first. Good luck.

Paul
 
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