My Exhaust leak

[Liquid Asset]

Ok, After taking all of my old exhaust blankets off yesterday I found what appears to be the leak. I am having trouble Identifying it. It appears that the exhaust leak is coming from the seal identified by the arrow on the right.

The part on the right that is not painted was covered by an exhaust blanket. It appears that the leak is coming from where the middle arrow is. But I can not imagine that there would be a leak there. Doesnt the large spacer keep the water in the exhaust manifold?

If yall could shed some insight onto this I woudl appreciate it.

[Genesis]

That is definitely a problem

[Liquid Asset]

By the way, does anyone have a breakdown of this? I can not find it in my Detroit manual. I do not want to dive into this without knowing what I am looking at. I need to get it fixed ASAP so I can start using the boat again.

By the way, Can a Turbo leak exhaust between the intake and Exit side?

[hattitude]

By the way, Can a Turbo leak exhaust between the intake and Exit side?

If I understood you correctly the answer is yes.

There are two "chambers" to a turbo, both with bladed wheels, connected by a common shaft. If there is soot between the two "chambers" and it is not there because it was directed there by the exhaust blankets from an outboard leak, then you have a leak in the inside exhaust housing. I had a similar leak and had my turbo rebuilt. The problem was solved.

Your exhaust joint is a design I am not familiar with, but I have had good luck sealing problem exhaust joints with Silkolene 762 hi-temp jointing compound.

Good luck,

Bernie

[Genesis]

The hotpipe comes off with just the bolts that are obvious. Between the hotpipe and the manifold (which is water cooled by the engine coolant) should be a metal gasket.

It appears you have two spacers between the manifold and hotpipe - that's a bit unusual but was likely done due to exhaust geometry issues and is of no consequence other than giving you more bolts to remove.

Get new gaskets, clean up the mating surfaces, and coat both sides of the new gasket LIGHTLY with Silkolene. Reassemble. Note that the Silkolene will smoke to beat the band on first use - this is NORMAL as its a heat-set compound.

That should fix it, providing the leak isin't in the pipe itself - it PROBABLY isn't.

Take your time getting the bolts out if they appear frozen. The hot pipe and manifold are both cast iron and if you break either, or break a bolt off in the manifold, you will be most unhappy. The latter (broken or damaged manifold) is EXTREMELY bad as replacements are absolutely stupid expensive.

BTW, expect that your inter (or after) coolers are nasty fouled - exhaust lekas usually do that.

[Liquid Asset]

I am going to pull the Intercoolers and clean them. I know they are probably really fouled. The turbos are fouled too, I know this because they air filters were black after bringing the boat home from Ft. Lauderdale. I ususally woudl not have run the boat knowing I had this leak, but It had to come home so I could do the work.

My turbos are filthy too. But I think I may have an exhaust leak on one or possibly two of them. What I didn't know is are there seals that could have not been replaced when they cleaned the turbos back when we purchased the boat, or could it appear to have an exhaust leak because of the exhaust leak I have on the up pipe?
What is the opionion of exhaust risers. I have been looking around and there are some people who offer riser coatings that are hard fiberglass with fire retardant resin. Is there an advantage to that over the soft blankes which are a pain in the butt. I need to have new blankets made, but since I have them off, I could remove the risers and send them to someone for a hard coating.

[Genesis]

I would not with the existing hotpipes.

They erode from the inside and if they're original they may have only half (or less!) of their wall thickness left. You will eventually have to replace them. BTW they ARE available and the last time I had to buy one (I managed to break a turbo stud on Gigabite by being hasty instead of patient when changing a turbo) they only cost $150 or so - they're not THAT bad.

I like the hardcoat on the exhaust from the turbo back, but not on the hotpipes. Part of the problem is that the flanges have to be covered, and you can't and still get bolts in them. You do NOT want those flanges sitting out there without insulation over them - the burn risk will be extreme. You're talking about 800F+ temperatures in there....

I'd just do the blankets myself....

BTW the turbos can leak from the exhaust housing half-seals. Fairly common, especially if the exhaust from the turbo back is not properly supported and is putting too much torque on the housing. If you've got carbon there its probably not from this leak - you likely have two leaks and need to address both.

[Liquid Asset]

Here is a picture of the turbo. The arrow points to the area where the soot is located. I dont know where it si coming from, but I am sure there is a leak somewhere.

[Genesis]

Oh, you have those infamous turbos with Monmon clamps.... those things are known to have leaking problems.

Its the turbo. It'll have to be taken apart (the exhaust side) and re-sealed. While you're at it check the supports for the piping from the turbo back to the exhaust, and if its inadequately supported, do something about that to prevent it from happening again.

[SKYCHENEY]

Are you sure that's an exhaust leak there and not an oil leak? If oil leaks there it vaporizes on the red hot turbo and really creates a mess. Was there oil on the blankets?