Crankshaft
Team Owner
Joined: Apr 1999
Posts: 21,953
Likes: 1,445
From: Reno Nevada
2024 C3 of the Year Finalist- Modified
If the bearing surfaces look good without scoring ( minor deffects can be polished out) I don't believe in under grinding forged cranks.
The other check is straightness. The crank can't be bent from end to end. Cranks can be straightened
The other check is straightness. The crank can't be bent from end to end. Cranks can be straightened
Team Owner
Joined: Apr 1999
Posts: 21,953
Likes: 1,445
From: Reno Nevada
2024 C3 of the Year Finalist- Modified
Intermediate
Joined: Sep 2012
Posts: 35
Likes: 0
Take it to a good automotive machinist. He can check it for straightness in a special fixture, magnaflux it for cracks, and check the journals for scoring and if they are slightly eggshaped or not. There is not a thing wrong with having a crank turned .010, as long as the guy doing it knows what he is doing. This will not penetrate the induction hardess. These checks are not expensive.
I am not sure what you mean by "the sleeves". Has the block had sleeves installed to repair some cylinders, or maybe it is an aluminum block, or are you referring to the main bearing shells as sleeves? If you are talking about the bearings, never reuse them.
I am not sure what you mean by "the sleeves". Has the block had sleeves installed to repair some cylinders, or maybe it is an aluminum block, or are you referring to the main bearing shells as sleeves? If you are talking about the bearings, never reuse them.
Thread Starter
Racer
Joined: May 2010
Posts: 370
Likes: 0
From: Westminster
Talking about main bearing shells as sleeves should i replace when i get the crank turned? And if i need new ones should i just call eagle?
If i take the crank and get it turned .010 should i also take the cam? never heard of the brand it is EPI?
Engine Block just a 4 bolt 350.
The problem with the engine was water in number 6 and 8 and 5 and 7 and flywheel wouldnt engage the starter and when it did it would grind.
If i take the crank and get it turned .010 should i also take the cam? never heard of the brand it is EPI?
Engine Block just a 4 bolt 350.
The problem with the engine was water in number 6 and 8 and 5 and 7 and flywheel wouldnt engage the starter and when it did it would grind.
Le Mans Master
Joined: Apr 2007
Posts: 7,353
Likes: 72
From: Graceland in a Not Correctly Restored Stingray
IF the crank has been nitrided, turning it .010" will remove the hardened surface, necessitating re-processing.
And, if you have the crank re-sized at all you'll need new bearings. That said, all it might need is a good micro-polishing. Without pics (at least) we're somewhat guessing in the dark, but any decent shop will know what to and not to recommend.
And, if you have the crank re-sized at all you'll need new bearings. That said, all it might need is a good micro-polishing. Without pics (at least) we're somewhat guessing in the dark, but any decent shop will know what to and not to recommend.
Last edited by TheSkunkWorks; Nov 18, 2012 at 08:06 PM.
Race Director
Joined: Nov 2002
Posts: 12,142
Likes: 54
From: Taylor Michigan
A preliminary test
a quick and easy way without a set of 'mikes is to draw your fingernail across the journals...if your nail catches then your warned its not right....then its off to the parts house/machine shop and let them explain what you need....
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Melting Slicks
Joined: Feb 2006
Posts: 3,428
Likes: 5
From: Japan
As for straightness, you can pretty much tell by putting new bearings into the block, oiling them, dropping the crank in, torquing the caps down, and turning it. The crank should rotate smootly with no change in rotational drag as it turns. If it 'sticks' or tightens as you're turning it that's a good indication that someting isn't quite 'plumb'; either you have some journal misalingment that would require align boring to correct or a bent crank or a combination of both. In agreement with the others, you can tell by visually inspecting the journals if the crank need cutting or polishing. Scratches, cuts, or gouges should be polished out but I wouldn't go turning the crank .010" under unless I had a real good reason to do so.
Those Eagle cranks are heavy and they're also real tough, so it would have taken something pretty severe to damage it as badly as you seem to suspect...
Those Eagle cranks are heavy and they're also real tough, so it would have taken something pretty severe to damage it as badly as you seem to suspect...