Leaking exhaust manifold gasket

[toyotafreak]

My port side exhaust manifold is leaking from three cylinders. Smelt it, and used tubing as a stethoscope - I can distinctly hear puffing sounds hitting the end of the tubing. I didn't find any evidence of the manifold actually leaking, just the gasket.

So what do I do?

Take the manifold off, clean both surfaces and replace the gasket? Is a bit of sandpaper and steel wool good enough?

Mr. Cohn would you recommend going to the local dealer for the gasket in the interest of time?

Any suggestions are welcome.

[westtx]

Other than the leak, is the boat running good again?

[Capt Rick]

No these are marine gaskets
1717350021   Gasket,ExhaustManifold      $25.70

Remove both manifolds, use flash- light to look inside where exhaust is to see if any water or rust is there. Also connect garden hose to intake side using the rubber hose and clamp. allow water to run thru manifold and out. like it is installed on engine . If there is a crack it shows up with water in exhaust chamber usually at middle chambers....Replace both manifold if leak is found on one. 

[toyotafreak]

Scott, no it's still running rough but I haven't swapped out plugs yet. Drained tank and filter, added FI cleaner and new Chevron Super ($3.60). Pulled a bit of excess oil; now dead on. One by one pulled spark plugs while idling on hose - each affected idle, although possibly some less than others. No oil in any spark plug hole. It was during the plug-ex that I followed up on the clicking noise. Will install the new plugs after squaring away the exhaust leaks. My gut tells me it's not plugs or bad fuel. I'm fearing fuel injectors and/or fuel pumps. We'll see.

Capt., thanks for the help. When you say look inside for rust, you're talking manifold, right?

Please let me know why to remove both sides, and also to replace both if one has problem. I only ask because my partner just had this problem with his 03 Centurion (350 Magnum) and was counseled to only disturb the problem side, not both.

[Capt Rick]

If the manifold get a crack and allows water into engine that may cost alot more then changing out exhaust manifolds. If one has failed the other will fail within 400 hours from my experience. Look for rust stain inside exhaust manifold. If the oil is milky or raised that is a sign of bad manifold. You can pull 1 injector harness at a time to see if they are firing..

Clicking noises and rattles are ok on this engine under 1000 rpm..

[toyotafreak]

Thanks, sir. On my way out right now...

[toyotafreak]

I can't figure out how to get the multiple attachments to work. Forum looks all funny too. Will try to post the pics I have ready when I can figure out what's wrong.

Scary stuff. As soon as I got the ski tow frame out of the way I noticed the exhaust manifold is dented in the same location that the valve cover is dented. I had seen the valve cover dent some time ago and have been keeping an eye on it to see if it ends up cracking through. There does seem to be a tiny amount of oil beginning to get through. The paint is not nicked or scratched, so I think this dent must have happened before painting while the engine was in a crate or like it got banged into something while being moved around.

It apears that every cylinder on that side is leaking and that one of them has other problems. It's unusually dark and wet. There is a bit of fresh oil around the exhaust port, inside the gasket and on the inside of the manifold. There is a bit of water inside the manifold and perhaps some inside the head's exhaust port for that cylinder.

I will ask for your help, Capt. in getting with Toyota about the manifold and valve cover. Things are obviously out of warranty, but I'm sure he'll discuss a latent defect like this that obviously came from the factory. However, I'm a bit concerned about the water and oil.

If it were just that the plug for that cylinder were fouled, it would explain the dark deposits, but how does that oil get there? Or the water? I noticed your coment above oil rising, and I did catchthe oil level higher than I thought I filled to during service. It's not milky, even after a weekend of running, but I can't help but wonder if there's a head gasket or block problem.

Please look at these pics and gimme some feedback.

[toyotafreak]

one through five

[toyotafreak]

six

[toyotafreak]

eleven through fifteen

[toyotafreak]

sixteen just for you all that think v-drive are hard to work on. The aft bulkheads come out with just a couple screws up top and down low - then you have acces to tons of engine.

[toyotafreak]

My bad. Here's sixteen.

[Capt Rick]

1. did you pressure test manifolds....
2. need hull number to look at history
3. That is not latent defect that is screw driver or prybar damage....
4. drain oil into clear containers and see if milky or water on bottom

[Rambling Wreck]

I am leaving the country for 2 weeks tomorrow so I won't know the answer to #1 until I return. I figure I will hear the response to #3 even in Europe-

[Capt Rick]

email me the hull number
toyotav8bt@aol.com