Impeller pieces?
 

1999 502 MAG, one riser is much hotter to the touch than the other, and is blowing a lot of steam after coming off plane. I replaced the riser/manifold gasket, it looked like the old one had failed. Still having the same issue. Manifolds and risers are only a year old, water passages seemed fine in both. Pulled off raw water pump and that looked fine too, the housing and impeller are only a year old

Last year I shredded an impeller. I thought I got most of the pieces out from the bottom of the oil cooler and from a backflush.

The only thing I can think of is that there is a blockage somewhere past the oil cooler that is diverting water to the port side, causing the starboard side to run hot and steam. Where should I look for this??

how is the water flow through the exhaust?? both side are about the same?

Do the 502's have those little ball and spring deals in the T-stat houseing? I had one of those freeze up and cause a similiar issue. Super easy to figure out just pull the hoses off. When you had the housing and impeller off were thery ANY scores at all? Last thing to look at is a couple weeks ago a friend had his raw water shut off start to close off on him. Make sure if you have one it is open and if you have a sea strainer it is clean.

Thanks guys, water flow is fairly even although now that I know that the one side is steaming my mind wants to tell me that there's less water on that side...

Gonna pull apart the T-Stat and take a look at that.

One questions though, do the PS cooler and/or the fuel cooler have the same kind of grates like the bottom of the oil cooler? I pulled old impeller pieces from the oil cooler, but since the other two are before that, I'm wondering if they have grates to stop debris as well.

Tom

If you do shred an impeller on a closed loop cooled set up, whats the best way to make sure you got all the pieces out? I have a buddy who was running his boat on the muffs and they slipped off and he smoked the impeller.

Thanks for the input and SORRY for the semi hijack

Michael

Not worried about the hijack, but mine's raw water cooled, so I have no idea about fresh water cooled systems.

the best thing is to reconstruct the impellor as you pull the parts out. if it came apart you can usually fit the pieces back to where they came from till you can build a complete impellor. unfortunatly if it got realy hot or if you changed the impellor and have run it some that gets tougher as some small parts may be long gone.

ck all your coolers, have to removed to be sure..have seen lots of stuff caught in P/S cooler