INBOARD HEAD-SCRATCHER

I have a Ski Nautique we decided to repower with a new, factory re-built 351 Ford engine. This is an old (1974), straight inboard boat. The old engine had a lot of crankcase pressure and was blowing oil out. Otherwise it ran great. <br />We bought an engine, ordering a counter rotation 351. When it arrived, we installed it and when trying to put in the distributor, realized it was a standard rotation engine. Sent it back after receiving the correct engine. Installed this engine, cranked it up and began the break-in. The first time we exceed 2,000 rpm's it starts to knock. We eliminated all possibilities, leading us t the conclusion it was a main bearing knock. The supplier sent us another engine which we installed with extra care. Thoroughly cleaned everything. Primed the engine thoroughly. Within a matter of hours, and again when first accelerating beyond 2,000 rpm's, it starts to knock. Same knock.<br />We call back the supplier and they tell us the first engine failed due to a lack of lubrication in # 8. And it's our fault. I can't figure how they determined this. Both engines always had0 oil pressure. The only way I see that I could cause a lack of lubrication is by not putting oil in the engine. And if that was the case, there would be a lack of lubrication everywhere, not just # 8.<br />We pull out the second engine and do a little investigation. They had subsequently told me that the rear main bearing on the first engine was bad. We take off all the main bearing caps and all are good except the rear one. It's smoked. The rod bearings being fed oil behind this bearing are undamaged. This indicated to me that there was no "lack of lubrication" to that bearing but something else was obviously wrong with both engines. Any ideas? I need the opinion of an unbiased, Ford (counter-rotation), mechanic. <br />We're still waiting to hear if they plan on standing behind their warrantee. I just want to make sure this won't happen again. We've installed this engine 3 times now. I want the next time to be the last.

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I've never worked on a ccw engine or this type of inboard, but....<br />- is it possible that whatever you are bolting up to the flywheel is out of alignment with the center-line of the crank causing a side-load condition?<br />- is it the upper or lower bearing shell thats bad or both halves?<br />- I find it a little strange that a 'main' bearing will cause knock. I've seen mains worn .020 and still didn't knock. rods of course are a different story....(something in the drive-line causing binding...knocking?)<br />- is it possible that the bearing installed doesn't line up with a oil journal in block? (wrong bearing?)<br /><br />I'm no expert, so take it for what its worth...<br />Good luck!!<br />

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Hey CF094,<br />Was the original engine a counter-rotation? I think Schematic is on the right track with the out of alignment theory. <br />Backlash

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What factory did the engine?

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A flex plate bolts directly to the flywheel. it accepts a splined input shaft from the transmission, which is bolted via bell housing, to the engine block. The output shaft of the transmission bolts to a coupler on the end of the straight/drive, drive (prop) shaft. The only place an out of alignment situation can occur is where the shaft bolts to the transmission. We did have an alignment problem which was quite obvious, resulting in vibration. After careful, and several adjustments, we eliminated all vibration. <br /><br />Your theory sounds logical, but I think between the transmission and the flex plate to buffer any stresses, the crankshaft shouldn't be affected. Correct me if you think I'm wrong.

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Haven't got a clue what you're working on, but....<br />-what kind of adjustments did you perform?<br />-flex plate won't compensate for lateral (up and down)misalignment.(not the ones I've seen)<br />- do any of you splined shafts have a grease zerk? over-greasing puts an unbelievable, incredible, ridiculous amount of strain on the drivetrain.<br />- is this similiar to an automotive transmission and bell housing arrangement?<br />- remove plugs > everything in neutral > turn engine over by hand(1/2" rachet handle on dampner bolt)take note of effort required(maybe use a torque wrench) > back out bell housing Bolts 1/4" > turn engine over again (is it easier?)lift up on trans..push to left...push to right...does it get easier in any one position compared to being bolted up <br />-I've seen some applications that require you to actually dial in(using a dial-indicator on crank to bell housing bore) a new engine to a bell-housing and redowl the housing.<br />-Maybe I'm out to lunch with this misalignment thing, maybe its just bad rebuilding(wrong rear main bearing) but one thing is for sure..........DON'T CONTACT THE REBUILDER UNTIL YOU IDENTIFY THE ISSUE, CAUSE IF HE COMES OVER AND SPOTS THE PROBLEM.....YOUR WARRANTY IS ----ED<br />Good luck!!<br />

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Bell housing/transmission arrangement is the same as an automotive, standard transmission. Unfortunately, the latest engine has already been shipped back to the supplier. It still doesn't seem possible to me that any stresses could be transmitted to the crank, when the transmission is bolted up tight to the engine. It's a good suggestion though. I'll be sure to do this test before cranking up the next one. Thanks a bunch for your input. If you or anybody else has anything else please let me know. I'll keep you posted with our status here.

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Yo: I have to agree, if you have a conventional clutch and transmission, it would be hard to misalign it. I wasn't sure what you were dealing with. <br />-did the clutch release properly(usually won't if disc put in backwards) <br />-was the oil hole in bearing lined up to oil journal?<br />-was the bearing blue?<br />-how high was oil pressure?<br />-are you absolutely sure the negative battery cable was connected directly to engine block?<br />-no ground cables were 'missed' or broken?<br /><br />Aint a whole lot left that you should have to be accountable for.....<br /><br />Good luck....be sure to let us know!!

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There's no clutch. Forward, neutral, & reverse, "Velvet Drive" transmission. I wish I'd looked closer at the bearing/oil journals. Too late now. The bad bearing was gold colored, down to the... Brass? Oil looked like a gold metalflake paint. Oil pressure was always 40 lbs. <br /><br />Now I'm trying to figure out where you're going with the battery ground question. The negative cable was bolted directly to the block. It's possible, thinking back that there could have also been a ground strap, can't remember. Maybe from transmission to block? Wouldn't seem necessary anyway. So tell me, where was the question going????

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I've wracked my brain trying to figure out something we could have done wrong. I just can't find it and they say they couldn't have built two bad engines. Still waiting to hear from them on the second, sent back engine. Will let you know their response.<br /><br />I'll have to think about your latest theory, tomorrow when I'm not so tired. Thanks again.

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how did the thrust main bearing look?(#3i think)

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May sound dumb but is the boat sitting at such an angle that it is throwing off the normal flow of oil? It's under pressure so it shouldn't matter but after reading everything, you have a real mystery.

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got some good info coming......don't beat yourself up yet!!!!!!!<br />

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<br /><br />-Another issue with the 351(not sure if windsor or cleveland) was the failure to drill the rear main bearing oil journal all the way through to the main oil gallery.(partially through, or not at all) This resulted in oil starvation at high speeds. If engine rpm kept low, engine would last, but if high rpm was kept up for a while.....rear main failure!<br /><br />-To rule this out along with improper bearing installation....before you install the next engine.......mount engine on stand > pan off > remove oil sender > connect up and pressure up engine with external oil source > let sit under pressure for a few minutes > count drips from each bearing journal and compare(low drips=low lubing=bad rebuild). If you don't have a 'pig' (external pressured oil supply) its easy to build one for cheap.<br /><br />-one last thing.....is it possible to install the flexplate backwards and have the trans input splines bottom out on the flexplate splines causing preload? When you bolt up the next engine to the trans. check for crank end-play(easy to do right from the dampner)<br />-and as we discussed.....don't forget the ground cable issue(Caa)cover all angles....<br />Good Luck man....

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Schematic, I don't know how you do it!! What is your background? I am amazed at the lengths the good people of this board will go to help each other out. <br /><br />Good luck and keep up the great work.<br /><br />Liam

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I definately second that comment. I'll print all this right now so we don't forget to check everything when we get the next engine. Still now word from the rebuilder. I'll keep you posted. Thanks again for everything.

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Thanks guys, its comments and appreciation that you guys show that makes this fun...<br />

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Just wanted to let you know that the re-builder has indicated to my shop guys that they will stand behind the warrantee. No explanation yet. I wonder if they found something they were doing wrong. I'll keep you posted. <br />Schmatic... If your ever going to Miami I'd love to take you fishing. Let me know. CFO94@AOL

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clanton...I just noticed that you're in Florida. The factory that built my engine is in Florida. Do you have anything to tell me?