Mercruiser Dry Joint Manifold?

[pete636ua]

How do I tell if I have the dry joint manifolds?? - I am having an overheat problem from time to time at cruising speed and am wondering if I should pull the manifolds/riser to check for blockage???

Its a 1999 5.0L Mercruiser S#OL353167

Used only in freshwater - new impeller yearly.

Thanks
Pete

 

[Don S]

Re: Mercruiser Dry Joint Manifold?

You don't have the dry joint exhaust, but it wouldn't hurt to pull the risers and look.
Might also check the water hose from the drive pivot housing to the transom shield to make sure there are no kinks in it.
If it's a raw water cooled system you might want to replace the thermostat. The do build up with crud after a while.

 

[pete636ua]

Re: Mercruiser Dry Joint Manifold?

Don thanks for your advice!!

Here is a better explaination of what is happening...

The boat gets new impellers every season(twins). Hear and there(not often) when cruising the Starboard engines temp alarm sounds - I drop down off plane and it cools down then I am able to cruise for days(seems like) without problems....has happened a few times over the last 3 seasons....Today same thing happened - ran all day no problems on saturday - on sunday coming into port the alarm sounds - I dropped off of plane put starboard in reverse for a sec and the engine cooled down (noted jumpy temp gauge) - I went back on plane and went for another 2 miles with out trouble at the same rpm...weird that I might always be getting weeds on this side??!! The engine has had 2 new T-stats over last 3 seasons and even when changed it dodn't seem to fix the problem - I have opened the drains on the block and manifolds and tried to flush as best as possible....It has a serpentine belt with age unknown although it looks in good shape...could that be it?? What about the exhaust flappers? Haven't noted any type of water leaks anyplace inside the boat - anyway any help is appreciated!!

Thanks
Pete

ENGINE S# OL353167