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43L SNAFU

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CJ Inglis

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" I have... had an 87 4.3L OMC

" I have... had an 87 4.3L OMC engine in my Celebrity. A couple of years ago, I was deployed over the winter and, long story short, cracked block and head. Then I deployed to Korea for about 15 months and once I finally came back, my buddy, who was storing the boat was in the desert. OK, brings me to now. Last weekend we rebuilt an 87 Monte Carlo engine and dropped it into the boat. We used the camout of the OMC but kept the crank from the Chevy. He had to get back to KY so I finished up with putting all the marine accessories back on (alt, exhaust, etc...). Here's the problem. It won't start. All cylinders have good spark. The distributer IS in right. I've checked it 3 times now. Odd thing though is that only cylinders 5 and 6 seem to be getting wet. I've pulled the plugs several times and the rest seem to be clean and dry???
Time for the question. Does anyone know if useing the car crank with marine cam might be the problem? This is the 4th engine I've ever built but its' got me frustrated. My next step is to ensure that the pistons are on the compression stroke at the right time. I know the #1 is but haven't checked the rest. In fact, I just thought of that as I was typing.
Any suggestions would be appreciated.

CJ "
 
" If the firing order on your

" If the firing order on your original engine is the same as the firing order of the new engine (in its original application) then there should not be a problem with using the marine cam with the automotive crank. If they were not set up to fire in the same order, then you would need to change the crank in order to match the cam timing to the pistons.

Keep in mind though, that if you did not re-ring the new engine, and you change the cranks (I assume you would use new main and rod bearings) then this could slightly change how far up the cylender the piston will travel, and could result in a broken ring if there is a ridge at the top of the cylender. "
 
" Good point. I did re-ring th

" Good point. I did re-ring the new engine and kept the old crank specifically for that reason. There was a pretty good ridge on the cylinders and honing didn't remove it. I didn't replace the mains because I never took the crank out. By the time we got it all apart, I realized that we didn't have the parts for that job and time was limited. In any event, I had read that the marine and auto engines were the same except for the manifold and carb. In fact, I read that here somewhere. That was my biggest concern. I think the problem may just be bad fuel. I hope so anyway. I am going to check the compression order this evening and cross my fingers. Thanks for the input though. "
 
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