Exhaust Riser?

[Jack2048]

I think I need a new exhaust manifold and risers.
Is there a way to check this?

I haven't run my engine in 5+ years. The risers are 13+ years old.
I started the engine and it ran, not with water. I then did maintenance on it, new water pumps, refreshed electrical connections, and other things. Now, when I start it, with water hooked up, it runs for a bit, then quits and won't restart. I let it sit overnight and it started.

So, since the only difference is it is not failing with water running through the system, I wanted to check the manifolds. Not sure how to determine if they are bad.

Or are you going to say, due to age, and that I run in brackish water, replace anyways, end of life?

Thanks.

 

[Scott Danforth]

You pull the elbows and risers. You clean the mating surfaces, and do a visual inspection. If they need replacement, then you replace them

 

[Jack2048]

You pull the elbows and risers. You clean the mating surfaces, and do a visual inspection. If they need replacement, then you replace them

Ok, will do, thanks. Probably going to need new gaskets for the engine block, I would imagine.

 

[Lou C]

Yep you replace them, it is not a complex job
However, the not running part, is a seperate problem, probably related to it not being used for 5 years. Probably have bad fuel that needs to be pumped out and the fuel system cleaned from the pump to the carb (or fuel injection).
And running it without water, you have to now replace the impeller, maybe the rubber exhaust hoses, you can check them when you have the exhaust off.

 

[Jack2048]

Yep you replace them, it is not a complex job

Yup. Did that when I first bought the boat. I saw water leaking between the riser and the manifold. The manifolds were practically welded to the block had to hit them fairly hard to get them off.

However, the not running part, is a seperate problem, probably related to it not being used for 5 years.

To clarify, I did have it running, not for long, w/o water. Worked fine.
Only ran into a problem when I hooked up the water.
That's why I suspect something in the exhaust area.

Probably have bad fuel that needs to be pumped out and the fuel system cleaned from the pump to the carb (or fuel injection).

Ran it on fresh gas, straight from a can. The tank is empty, been reglassing the hull. Fuel Injected. Did have the injectors cleaned.

And running it without water, you have to now replace the impeller, maybe the rubber exhaust hoses, you can check them when you have the exhaust off.

I initially ran it w/o the pump as I had to replace the whole pump since it was in such bad shape. Had to replace the circulating pump too.

 

[Bondo]

I think I need a new exhaust manifold and risers.
Is there a way to check this?

I haven't run my engine in 5+ years. The risers are 13+ years old.
I started the engine and it ran, not with water. I then did maintenance on it, new water pumps, refreshed electrical connections, and other things. Now, when I start it, with water hooked up, it runs for a bit, then quits and won't restart. I let it sit overnight and it started.

So, since the only difference is it is not failing with water running through the system, I wanted to check the manifolds. Not sure how to determine if they are bad.

Or are you going to say, due to age, and that I run in brackish water, replace anyways, end of life?

Thanks.

Ayuh,..... You pull the risers off the manifolds, clean the gasket surfaces to clean metal, 'n measure the width of the surfaces,.....
New, is 'bout 1/4 inch or wider,....
Failing is when the surfaces can no longer support the gaskets,.....

Many times, they can be brought back to spec with a flat file, or a belt sander,.....

 

[BRICH1260]

Are you getting any overheating alarms? Do the risers feel hot to touch? If not, the stoppage in running is probably not related to the manifold/risers.

 

[Jack2048]

Are you getting any overheating alarms? Do the risers feel hot to touch? If not, the stoppage in running is probably not related to the manifold/risers.

The engine quits a few seconds after starting.

 

[Jack2048]

I pulled the risers and manifolds. As I suspected, I found water in part of the port manifold. The engine mounting surfaces look fine. The riser mating surfaces don't look too bad. I will try cleaning them up and getting new gaskets.
See attached pics, these are the port side, starboard is about the same.

 

[flashback]

Looks good to me, you even got the gasket off in one piece,

 

[Lou C]

They do look pretty good, you'll be able to tell better when the sealing surfaces are totally cleaned up.

 

[Scott Danforth]

Run a large bastard file across them and get thru the putting

Also clean out the crusty flakes. I use a section of 3/16 cable in a drill motor

 

[Jack2048]

Using a not so "large bastard file". Not through the putting/pitting yet. The starboard side was much worse.

 

[Jack2048]

A before and after of the riser.
Will work on the manifolds tomorrow.

 

[Scott Danforth]

Looks like a bit more should be taken off to clean up the left side of the exhaust passage.

 

[flashback]

How is the condition of the snout end of your riser?

 

[Jack2048]

How is the condition of the snout end of your riser?

Well, ya just had to go and ask that question.
I took the rubber boots off, and some rusted pieces fell off, but not too bad.

 

[flashback]

Changed mine a while back and they looked a whole lot worse. You probably got a few more seasons but keep a close watch.

 

[Jack2048]

Changed mine a while back and they looked a whole lot worse. You probably got a few more seasons but keep a close watch.

Did you put any high temp paint on them?

 

[stresspoint]

Yup. Did that when I first bought the boat. I saw water leaking between the riser and the manifold. The manifolds were practically welded to the block had to hit them fairly hard to get them off.


To clarify, I did have it running, not for long, w/o water. Worked fine.
Only ran into a problem when I hooked up the water.
That's why I suspect something in the exhaust area.


Ran it on fresh gas, straight from a can. The tank is empty, been reglassing the hull. Fuel Injected. Did have the injectors cleaned.


I initially ran it w/o the pump as I had to replace the whole pump since it was in such bad shape. Had to replace the circulating pump too.

its never a good thing to run without the water going through.
that said: there are a few things to note ,
was the water pump impeller intact , if not parts of the impeller may have got around the internals of the motor and blocked stuff up .

the other thing to check is the T stat , over time they get a build up and close up .

pull all the hoses and run water through , use a rag around the hose to create a seal , water should flow free thou out the system.

im guessing the cutting out is not to do with the water flow , more likely a clog in the fuel system flush the system and check the FP is operating properly or an electrical issue , check the power going to all the systems.