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I'm No Expert
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Discussion Starter #1
Well the motor runs strong, sounds good, but when it's idleing i can bearly see alittle bit of white smoke when it's running out of the right (even side) bank. I'm pretty much positive i know what cylinder is causing the problem because when i pulled the plugs last time the number 6 plug was black and oily looking. When i saw i see white smoke at idle, i'm talking like you have to be up close and looking at exhaust to see it so it's not a huge amount but what does suck is at startup. When i start it up after i had shut it down and let it sit for a while a nice puff of white smoke comes out and then it cleans up. What do you guys think this could be, i'm guessing there's pretty much nothing i can do to fix this other than tear it down?
 

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Well the motor runs strong, sounds good, but when it's idleing i can bearly see alittle bit of white smoke when it's running out of the right (even side) bank. I'm pretty much positive i know what cylinder is causing the problem because when i pulled the plugs last time the number 6 plug was black and oily looking. When i saw i see white smoke at idle, i'm talking like you have to be up close and looking at exhaust to see it so it's not a huge amount but what does suck is at startup. When i start it up after i had shut it down and let it sit for a while a nice puff of white smoke comes out and then it cleans up. What do you guys think this could be, i'm guessing there's pretty much nothing i can do to fix this other than tear it down?
Shaun, Need info on the boat to think. M
 

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Well the motor runs strong, sounds good, but when it's idleing i can bearly see alittle bit of white smoke when it's running out of the right (even side) bank. I'm pretty much positive i know what cylinder is causing the problem because when i pulled the plugs last time the number 6 plug was black and oily looking. When i saw i see white smoke at idle, i'm talking like you have to be up close and looking at exhaust to see it so it's not a huge amount but what does suck is at startup. When i start it up after i had shut it down and let it sit for a while a nice puff of white smoke comes out and then it cleans up. What do you guys think this could be, i'm guessing there's pretty much nothing i can do to fix this other than tear it down?
Shaun, run a compresion check first and call me back. M
 

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Cantard
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My guess is that if its a bbc it is leaking water past an exhaust guide or the guide has a crack in it.
 

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My immediate guess would be guides but a leak down would help to determine if is rings. Ususally leaky guides puff smoke on start up then the smoke will disapate.
 

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I'm No Expert
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Discussion Starter #7
I should have gave this info in the original post but i did do a comp test a few months back when i was searching for my noise problem. All cyl where right around 180-185 if i remember correctly.

Before i put this motor together i gave bob mckray (think thats the spelling) these heads bare and he checked and assembled them.

ok, i've done a leak down before but it was a long time ago in autoshop, can anybody give me the proceedure again. From what i remember you do a comp test, then little oil in the cyl and do another comp test.
 

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How am i suppose to tell if it's a guide or not, from those instructions it tells you if your loosing comp through rings, int valve, or ext valve...
Listen to where the compression is going, pull the valve covers and LISTEN. If you are doing a leak down you do it with the valves adjusted and again with the valves backed off. Leak no leak heads or rings.M
 

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shaun, it's a valve guide seal. Are you running PC type or umbrella type. If its, a PC type, maybe came loose from the guide, if umbrella seal then maybe the guid is a little loose, but if definitely valve relateded. When you shut it off, any oil on the stem can run down past the seal and shows up when you fire it off. Smokes the most when the motor is stone cold, less when refired after setting awhile, and vertually nothing once it's warm and running. If it doesn't show up to bad on you plugs I wouldn't worry to much about it, unless it really bothers you.



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You are certain that this white smoke is isn't just some steam or a water related problem and the oil on the plug isn't something else?
I might be wrong, but it should give a puff of blue smoke if it's valve guide or seal related.

At this point, I wouldn't make too big a deal out of it. If it's not blowing constant or making any unusual noise, I'd say just keep on running it and enjoy the coming summer unless it becomes worse. At the very least, pull the valve cover on that side and visually inspect that the seals (the perfect circle type) are seated down on the guide. I have on more than one occasion found a seal or two taking a joy ride up on the valve stem.
I think you've done all you can so far without actually tearing into it. With that being said, there's always SOMETHINGthat needs attention with these kinds of boats. I'm right there with ya. I've got a loose stringer that needs replacing but just not right now.
 

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I'm No Expert
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Discussion Starter #15
So last night another guy in the jet section had a oily plug, they started telling him the same thing, do a leak down. What they also said was to check the intake gasket as it maybe wasnt sealing on that port. I started thinking about my build more and i realized my heads have these plugs in them. I put the plugs in, they where aluminum and i didnt use any sealer on them. I pulled the valve cover last night on that side and sure enough the port that goes to #6 has this plug right in it. I'm wondering if maybe the plug is not fully sealing and sucking in oil? Am i just crazy or is this a possibility? THese heads are drilled for extra head bolts, my block wasnt so i didnt use them.

 

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It's what we do
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shaun, it's a valve guide seal. Are you running PC type or umbrella type. If its, a PC type, maybe came loose from the guide, if umbrella seal then maybe the guid is a little loose, but if definitely valve relateded. When you shut it off, any oil on the stem can run down past the seal and shows up when you fire it off. Smokes the most when the motor is stone cold, less when refired after setting awhile, and vertually nothing once it's warm and running. If it doesn't show up to bad on you plugs I wouldn't worry to much about it, unless it really bothers you.
I agree
 

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Shaun, Back off all the valves and then pull all the plugs. Then seal the water exit and plumb the garden hose to the motor and give it full pressure. White smoke is water or ATF blue smoke is oil. If the water stops flowing and you can't hear any flowing then all should be good. Normal household water pressure is only 17 LBS and hopefully the motor holds that. If not, I would spin the motor by hand and as each cylinder comes to TDC check for water pouring out the plug holes. If #6 is fowling it could be a head gasket weeping and Might just be a re-torque. ENGINE DIAGNOSTICS SUCKS. M
 

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Some guy
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So last night another guy in the jet section had a oily plug, they started telling him the same thing, do a leak down. What they also said was to check the intake gasket as it maybe wasnt sealing on that port. I started thinking about my build more and i realized my heads have these plugs in them. I put the plugs in, they where aluminum and i didnt use any sealer on them. I pulled the valve cover last night on that side and sure enough the port that goes to #6 has this plug right in it. I'm wondering if maybe the plug is not fully sealing and sucking in oil? Am i just crazy or is this a possibility? THese heads are drilled for extra head bolts, my block wasnt so i didnt use them.

That should only take you a minute to remove the plug and put some sealer on it, worth a try? I would think it you have it snug it would not be leaking past the threads though.
 

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I'm No Expert
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Discussion Starter #20
went out and looked at it a bit. The seal looks to be staying on the guide, at least i tried to move it with a screw driver and i couldnt. Bob Said also that he doubted thats what was happening because if it would have came off that easy when he assembled these heads he wouldnt have left it like that. He wants me to pull the spings drop the valve a bit and try to wiggle it.

I pulled those plugs, they came out pretty easy. The plugs are steal, i put some rtv on them and cranked them back down. On the bottom of the plugs they where oily, i made sure to wipe off access oil before removing them so it wasnt oil that ran down i dont think.

I'm going to change the plugs, run it this next trip and see what it does.
 
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