S.O.S

Vondy if you're bored at work here's my msn. Luchog01@hotmail.com

OK, if I did this right, that exhaust manifold has a leak. I put the riser higher than the intake hose, filled the hose until I could see water in the riser drain plug hole. Water came out of number 1. The lowest. And all of them if I leveled it out.

So, if I did it right and my exhaust manifold is leaking, is it possible that's it or do I need to keep digging deeper?

Damn I really like the look of these manifolds, hope I can repair or find some more. It really makes the H/M.

David,
It sounds like you did the water test correctly as long as you didn't get the water high enough for it to enter the exhaust cavity via the ports in the riser elbow. These are the holes between the water jacket and the exhaust side where water enters the exhaust stream. It's why Chris told you to raise the riser elbow end higher.

Good you have the bolts loose. Try running them out against the elbow to the point where they start "jacking" against the elbow. Don't put too much pressure on them. You don't want to damage the aluminum threads is possible (they may not be in decent shape now). Then go at it with a putty knife. Then a wood chisel. If you damage ether face no big deal because I'd say they are going to need refacing anyway.

When you get them apart, you'll need to see if it's the manifold or the riser. Stand the manifold on end hose side down and fill the water jacket up to the top (elbow flange end).

Take a close look inside the elbow near the two plug holes I mentioned.

vondy wrote: So what do you guys think? Are we looking for two problems? Could that much water possibly get into the oil from the leaky manifold?

This question is really still up in the air!! Just as Lunciano said, it's hard to imagine you'd get that much water past the rings. However, I have no idea how much water it really takes to turn oil as milky as you found yours.

8122pbrainard wrote: vondy wrote: So what do you guys think? Are we looking for two problems? Could that much water possibly get into the oil from the leaky manifold? This question is really still up in the air!! Just as Lunciano said, it's hard to imagine you'd get that much water past the rings. However, I have no idea how much water it really takes to turn oil as milky as you found yours.

Hum....    Should I pull some more parts off or fix the exhaust and see what happens? I like the idea of borrowing another manifold but I don't know anyone. Might have to give Ryan's buddies a call.

Just thinking out loud here.....
Perhaps the manifold has been leaking for a while, giving me some starting problems as some have mentioned. I did have to open up the throttle to start after sitting on Sunday's trip. I figured I just did not have the carb tuned in yet.

Maybe the overheating compounded the problem to the point where much more water got into the cylinder. If I shut the boat down and it happens that that cylinders exhaust valve is open then the water could have pooled into the cylinder. Again, not knowing if it's enough to milkshake the oil.

vondy wrote:

David, This is great advise and in a perfect world will work BUT I've taken a set of H/M's apart that looked about as bad as yours do and do yourself a favor and drop them off at a machine shop that is better equiped to do this job. I tried everything above but what happens is even if you get the putty knife between the riser and the manifold they will still not want to come apart because the bolts are corroded in the flange holes.

I ended up cutting mine off and then had to drill and ez out the studs out of the manifolds, on some of them that still didn't work so I had to step up my drill sizes and then run a tap down the holes . It all worked out fine but you will spend hours on them and make a bigger mess of them than you can imagine. If you don't have the tools this is a big PITA.

[/QUOTE]

Good point. Is there a lip between these too joints are is it a simple butt joint?[/QUOTE]

butt joint

Alan,

I looked back at an old post of mine and found a pic you posted.



My post was about a leak at this joint. Don't know if that has anything to do with my issue now.

I also found some post back in 2007 stating that H/M was recasting these manifolds. Does anyone know if this ever came to be?

Thanks!

Thanks Pete, just might order some. Good to have around.

Luchog wrote: vondy reading again... I have my serious doubts you performed the leak test correctly... I will suggest again... you lay the manifold over as it is positioned in the boat (front slightly up, runners down) and send pressurised water in it through the water inlet. it's a 5 minutes test all you need is a garden hose held by hand. This way we'll make sure you are not opening the exhausts for nothing.

Your saying with the risers facing down right? I did not do that. I did 79's way. I'm not sure how water could be getting into the exhaust chamber without me having a leak of some sort.

Here's a rough illustration of what I did. Even if some water at the riser exit pooled over, it would have been a lot to make it back up the riser and into the manifold. I slowly filled it, no pressure, and stopped when I saw it crest at the upside-down riser exit. And it was full of water, not just a trickle.

So my guess is there's either a crack in there or the gasket between the riser and manifold is completely blown out internally.

Either way, I have dug enough of the gasket out trying to separate that I don't think there is any turning back.

Keep it coming guys. And tell me if I'm doing anything wrong in these procedures.

8122pbrainard wrote: David, It sounds like you did the water test correctly as long as you didn't get the water high enough for it to enter the exhaust cavity via the ports in the riser elbow. These are the holes between the water jacket and the exhaust side where water enters the exhaust stream. It's why Chris told you to raise the riser elbow end higher.

Seeing your sketch, just as Luciano, I too am now worried that you didn't get water into the exhaust side per the above. Look down into the elbow if you haven't already. You'll see the ports. That's were you do not want to get the water level high enough for it to enter the exhaust side.

yes that is true you should leave it about 1/4" short, just make sure that it didn't spill over the wall from water pressure as it was being filled, but if your getting a steady stream going out you should be able to see the level go down as your looking in to the riser's opening and at some point it should stop leaking once the water level matches the cracks level, so try driing it out and if more water keeps coming out then you have a leak internal to the manifold.

79nautique wrote: If your illustration is correct it's not the #4 cylinder it's either #1 or #5 depending on the side you pulled it off of. get the halfs separated, plug the endlet hoss, stand it on end and carefully pour water down the jacket if you see any water in the center exhaust section they are cracked, don't need pressurized water to find that out.

keep in mind that once water gets in the exhaust chamber it will exit the manifold through the lowest runner, in the engine it's number 4, but in the bench it could be any depending on how vondy placed it for testing.

vondy wrote: We read and old post where someone mentioned the PCM manual listing the top 10 reasons water get into the oil and cracked exhaust manifold was number 1.

I think we all really hope it is just that...

vondy wrote: We have a mechanic friend here who says water will get right passed the rings and it only takes a bit to milkshake. Thats what he says at least.

are you trying to convince us or yourself?