Eagle crank and chamfered bearings

[incharge]

Someone help me understand this I have a stock stroke Eagle crank and a set of King Main bearings with a RJC Girdle fresh back from the machine shop ,Went to install the crank and tighten the mains and the girdle and it spins alittle tight , took it apart and checked everything and it looks like the side of the bearings are rubbing on the radius of the journals, how can it be hitting there if I have about .0008 thousand end play back and forth?? was told thet I need to chamfer the bearings

 

[Jeff Rand]

Check the end play starting with the thrust bearing first. You might want to start with one half of the thrust (upper half in the block), then put the #2 cap on and check it and observe any loss in end play. Then put in another main bearing and check again to see if there is any reduction. You might have had more then .008" with just the thrust then the other mains reduced it down.
Jeff

 

[kingots2004]

good aftermarket cranks have a radius built up at the sides of the journal. regular cranks are flat across with very little radius the big radius gives the crank more strength. sounds to me like you do in fact need chamfered bearings. i cant believe the machine shop didn't tell you this. oh and be careful who machines the crank I've seen some machine shop turn this larger radius out of cranks which weakens them

 

[incharge]

But you would think that with .0008 end play that this would be enough to clear the radius on the journal??

 

[kingots2004]

measure the journal it tappers back futher than it looks if the crank calls for chamfered bearing your gonna have to run them.why even try to risk it for the money

 

[gnxtc2]

You have alot of variables. Did the machine shop line hone the mains with the girdle and heads attached? Yes, you might have to chamfer the bearing: mains and/or rods.

Did you set the thrust bearing before you tightened down the cap? Snug the cap down slightly and wack the crank with a plastic dead blow hammer from both ends to set the thrust.

Billy T.
gnxtc2@aol.com

 

[incharge]

Was lined honed with the girdle bolted down , heads were not on ..

 

[NC87GN]

Went through the same scenerio and had to chamfer my main bearing as well. Any reputable machine shop can do. Shop labor is about an hour.. HTH

Mike Banas
87GN

 

[gnxtc2]

Was lined honed with the girdle bolted down , heads were not on ..

Chamfer the bearings and see what happens.

Billy T.
gnxtc2@aol.com

 

[incharge]

Any ideas on how to do the chamfering myself ?? Dremel tool ?

 

[challengermike]

You have to use a bearing knife,and scrape a champher into them.Or by champhered bearings.My mopar 499 stroker i built i had to use ACL brand bearings.I dont know if they make them for buick.But i am sure somebody must make them.

 

[turbodave231]

You can check and find the points where the bearings are contacting the fillets using machist's blue. And .0008" is not enough end play in the crank.

I would not recommend attempting the chamfering yourself unless you are a good machinist. To do this properly, you will need a fixture and a lathe. I am setup to narrow rod bearings but I've not built a fixture for mains yet.

I believe Dan at DLS can supply chamfered bearings or chamfer yours.

 

[incharge]

I think the book states .003 to 0009. is the correct end play..

 

[turbodave231]

You better recheck your specs. .0008 is 8 ten thousandths.

I beleive the BMS book says the end play ought to be like .005