Found light cylinder scuff during upgrade
01-23-2019 | 07:24 PM
#22
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Joined: Jan 2002
Posts: 4,612
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From: ALTO, MI
If these were automotive bottom ends and You plan on putting a blower on it the bottom end should be taken apart and clearanced for marine high HP.
I bet you are going to find that the pistons are tight.
Spend the $ now OR spend the $$$ after it blows up.
Doing it right and bullet proof the first time is CHEAP.
BTDT
I bet you are going to find that the pistons are tight.
Spend the $ now OR spend the $$$ after it blows up.
Doing it right and bullet proof the first time is CHEAP.
BTDT
01-23-2019 | 07:48 PM
#23
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From: Buffalo, NY
Guys I found this light scuff taking one of my heads of last night. You cannot feel it with your finger but if you drag a finger nail on it you can just barely feel some light rumbles. These are GM ZZ572 crate motor bottom ends that have never been apart. They probably have 125-130 hours on them. Engine never burned any oil or smoked. I was hoping not to have to get into the bottom ends. What do you guys think??
01-23-2019 | 08:55 PM
#24
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From: Cedar Springs MI
Ya, actually I have been looking closer at the other cylinders and most of them have some very light scuffing at the north and south edges of the cylinders and some have light marks at all four corners. When I first bought this boat the timing was set to all in at 50 degrees. I caught it and fixed the timing issue, but with what Dan posted earlier wonder if to much timing caused these scuffs....?
01-23-2019 | 09:02 PM
#25
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From: Buffalo, NY
Ya, actually I have been looking closer at the other cylinders and most of them have some very light scuffing at the north and south edges of the cylinders and some have light marks at all four corners. When I first bought this boat the timing was set to all in at 50 degrees. I caught it and fixed the timing issue, but with what Dan posted earlier wonder if to much timing caused these scuffs....?
01-24-2019 | 11:21 AM
#28
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From: Northport N.Y.
Lol one day I wanted to cry lol. Only had about five hours on motors. Start of a poker run motors where cold had no corrections from close loop yet and was a cold day. Finished a cooler of beer on the way home on the other engine.
01-24-2019 | 03:47 PM
#29
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From: Cedar Springs MI
Talked with my local machinest this morning and I am bring him both short blocks. He will be doing final disassembly and inspection. Check the cranks, upgrade rod bolts and reman rods, hone cylinders with torque plate, new rings, new rod bearings, new crank bearings, and new cam bearings. They will wash block and reassemble short block with the appropriate clearances for a supercharged marine application. Little more money than I had expected to spend on this upgrade but I think it’s money very well spent for peace of mind!!!
Last edited by rob vanharten; 01-24-2019 at 03:49 PM.
