Exhaust riser hole !

[eminentguy]

Hello all

I noticed some unusual noise in my engine and noticed a drop in maximum rpm and speed I can reach recently.

Inspecting the exhaust riser (part 3863061) has a small hole where I could feel the gas leaking out from it and been told thats is the reason for (not water though) the speed drop ..

Am trying to use a welder to fix it now.. two questions please:
Is welding a bad idea?
Could this really be the reason for the drop in speed and maximum rpm?


Thanks for the great help and tips...

Firas

My engine: penta 5.7 osxi-gf

 

[Bondo]

Re: Exhaust riser hole !

Hello all

I noticed some unusual noise in my engine and noticed a drop in maximum rpm and speed I can reach recently.

Inspecting the exhaust riser (part 3863061) has a small hole where I could feel the gas leaking out from it and been told thats is the reason for (not water though) the speed drop ..

Am trying to use a welder to fix it now.. two questions please:
Is welding a bad idea?
Could this really be the reason for the drop in speed and maximum rpm?


Thanks for the great help and tips...

Firas

My engine: penta 5.7 osxi-gf

Ayuh,... Welcome Aboard,.... Got a picture or 2,..??

If it's cast iron, weldin' won't work,...

replacement is the usual Fix,..

 

[bruceb58]

Re: Exhaust riser hole !

If the riser is corroded enough that it has a hole, replace them. In salt water, normal time to replace is every 5 years.

 

[Ike-110722]

Re: Exhaust riser hole !

Replace it. You don't need the carbon monoxide and most of these risers are cast iron. Can't weld it.

 

[bruceb58]

Re: Exhaust riser hole !

Its not just what is happening on the outside. Could also be doing this between the water jacket and the exhaust itself which will cause water to enter the exhaust side when the engine is shut down, If your risers are in this condition, the manifolds are likely as well.

 

[dozer59044]

Re: Exhaust riser hole !

I had cracks in both of my risers. took all apart and inspected. Found that the cracks were only on the exterior side. so, I JB welded them. Its a temporary fix. But, until you can buy new risers( in my case $300 apiece) It does work.

 

[bruceb58]

Re: Exhaust riser hole !

I had cracks in both of my risers. took all apart and inspected. Found that the cracks were only on the exterior side. so, I JB welded them. Its a temporary fix. But, until you can buy new risers( in my case $300 apiece) It does work.

How can you possibly see if there are cracks inside? Basically impossible since it is impossible to pressure test a riser.

If you want to personally risk a $4k engine with old risers then so be it. Bad advice for others.