Help! Bought a 1993 Four Winns W/ 5.0 OMC Cobra Motor and Drive - Losing power after crusing

[cameron92]

Not bad ideally you want a warmed up engine & throttle wide open, I think they’d be higher then. Next leak down test and what did the air pressure test show? If all is good test your manifolds & try running it again. See if you still get water in the oil. Air pressure test is really the most important

The air pressure test is losing psi somewhere. I cant hear anything, smoke test didn't reveal anything. Thought maybe I could hear something in the valve cover but hard to say. I think it might be my setup, it is just a rubber ball that inflates and if I pump more then 12 psi it shoots out of the hose

 

[Lou C]

You have to get a better seal for a valid test

 

[Scott Danforth]

It just occurred to me that the previous owner installed a new distributor cap. He mentioned something about timing being out but he had a mechanic look at it. Wondering if that relates to my original issue.

Probably wired it to the wrong firing order

 

[cameron92]

So I tested my manifolds for leaks. Didn't have acetone but just filled the hose with water. The exhaust ports filled up with water as well after about 5 mins. Guessing that's my issue..

 

[Lou C]

I guess in freshwater you don't see the rust like we do here!
PS was the manifold sitting level when you tested it, because it could have run out the outlet of the elbow and then ran back in the center exhaust port and filled the exhaust ports if you tested it with it lying down like the pic! The only way to test a manifold with any liquid is with them standing straight up as installed on the engine!

 

[cameron92]

I guess in freshwater you don't see the rust like we do here!
PS was the manifold sitting level when you tested it, because it could have run out the outlet of the elbow and then ran back in the center exhaust port and filled the exhaust ports if you tested it with it lying down like the pic! The only way to test a manifold with any liquid is with them standing straight up as installed on the engine!

Oh! I was laying them down yes.

 

[Lou C]

Dry em out and try again!
You have water passages and exhaust passages inside those castings, the water must stay separate from the exhaust passage. I would be surprised if yours leak because there was no sign of rust in the exhaust ports in the cyl head or the exhaust ports on the manifold. Usually if they are leaking it's obvious from the amount of rust. The water passages are to keep the manifold at a resonable temp given that it's on an engine in a closed compartment. The exhaust gas flows up and out the elbow and the water does as well, but separately and they mix together when the water and exhaust exit the elbow inside the rubber hose. So if it's lying down like that, the water can flow backwards and wind up right in the exhaust ports.
Get in closer to the engine and see if you can get pix of the inside of the exhaust port on each cyl head and see what the exhaust valves look like. You should be easily able to see them.

 

[cameron92]

I guess in freshwater you don't see the rust like we do here!
PS was the manifold sitting level when you tested it, because it could have run out the outlet of the elbow and then ran back in the center exhaust port and filled the exhaust ports if you tested it with it lying down like the pic! The only way to test a manifold with any liquid is with them standing straight up as installed on the engine!

No relatively rust free!

Dry em out and try again!
You have water passages and exhaust passages inside those castings, the water must stay separate from the exhaust passage. I would be surprised if yours leak because there was no sign of rust in the exhaust ports in the cyl head or the exhaust ports on the manifold. Usually if they are leaking it's obvious from the amount of rust. The water passages are to keep the manifold at a resonable temp given that it's on an engine in a closed compartment. The exhaust gas flows up and out the elbow and the water does as well, but separately and they mix together when the water and exhaust exit the elbow inside the rubber hose. So if it's lying down like that, the water can flow backwards and wind up right in the exhaust ports.
Get in closer to the engine and see if you can get pix of the inside of the exhaust port on each cyl head and see what the exhaust valves look like. You should be easily able to see them.

Here's a video of all 8

 

[cameron92]

Dry em out and try again!
You have water passages and exhaust passages inside those castings, the water must stay separate from the exhaust passage. I would be surprised if yours leak because there was no sign of rust in the exhaust ports in the cyl head or the exhaust ports on the manifold. Usually if they are leaking it's obvious from the amount of rust. The water passages are to keep the manifold at a resonable temp given that it's on an engine in a closed compartment. The exhaust gas flows up and out the elbow and the water does as well, but separately and they mix together when the water and exhaust exit the elbow inside the rubber hose. So if it's lying down like that, the water can flow backwards and wind up right in the exhaust ports.
Get in closer to the engine and see if you can get pix of the inside of the exhaust port on each cyl head and see what the exhaust valves look like. You should be easily able to see them.

No water leakage. Obviously not the same as acetone but I figured it's better then nothing for now.

 

[cameron92]

If I reinstall my manifolds do I need fresh gaskets? Can I get away with automotive gaskets temporarily?