S/B rod clearance?
04-04-2004, 04:00 PM
#1
32' SUNSATION
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S/B rod clearance?
What should the clearance be between rods on a Small Block Chevy. The Rods Are ALUMINUM and It currently has .035 ?
This motor will spin 6000RPM and has 10:1 comp.
This motor will spin 6000RPM and has 10:1 comp.
04-04-2004, 05:00 PM
#4
MarineKinetics
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Kanookstr
Are you referering to bearing clearance or rod side clearance? .0035" rod bearing clearance is excessive and should be corrected. I would keep side clearance to .020
Bob
Are you referering to bearing clearance or rod side clearance? .0035" rod bearing clearance is excessive and should be corrected. I would keep side clearance to .020
Bob
Last edited by rmbuilder; 04-04-2004 at 05:04 PM.
04-04-2004, 05:09 PM
#6
MarineKinetics
Platinum Member
Kanookstr
Personally I would not use rods w/ .035 side clearance due to possible oil control issues. Are you thinking of using these in a marine engine?
Bob
Personally I would not use rods w/ .035 side clearance due to possible oil control issues. Are you thinking of using these in a marine engine?
Bob
Last edited by rmbuilder; 04-04-2004 at 05:12 PM.
04-04-2004, 05:13 PM
#7
32' SUNSATION
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I was afraid of that, but that's what I am stuck with.
Is it that serious, or will it survive with a high volume pump??? Hate to have to get a new crank, but if it won't work, I'll have too.
Yes this is for a marine application on a 2800lbs boat
Is it that serious, or will it survive with a high volume pump??? Hate to have to get a new crank, but if it won't work, I'll have too.
Yes this is for a marine application on a 2800lbs boat
04-04-2004, 05:30 PM
#8
MarineKinetics
Platinum Member
Kanookstr
A H/V pump wont cure the problem, it may even aggravate it. The oil exits via the side clearance between the rods dispersing oil to the camshaft, lower cylinder walls, and the underside of the piston crown. Oil control in certain areas is critical and if not properly managed can lead to engine failure. Especially in the case of getting past the oil ring and into the combustion chamber resulting in severe detonation.
Question:
Have the rods been clearanced or has the crank been ground resulting in the excessive clearances? I would not run aluminum rods in a marine engine.
Bob
A H/V pump wont cure the problem, it may even aggravate it. The oil exits via the side clearance between the rods dispersing oil to the camshaft, lower cylinder walls, and the underside of the piston crown. Oil control in certain areas is critical and if not properly managed can lead to engine failure. Especially in the case of getting past the oil ring and into the combustion chamber resulting in severe detonation.
Question:
Have the rods been clearanced or has the crank been ground resulting in the excessive clearances? I would not run aluminum rods in a marine engine.
Bob
Last edited by rmbuilder; 04-04-2004 at 05:47 PM.
04-04-2004, 06:50 PM
#9
32' SUNSATION
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The crank was ground resulting in this clearance.. The engine belongs to a friend of mine, and he asked me to ask about this. Is there any suggestions as to how to fix the problem without replacing the crank?? He's on a tight budget.
