'92 Mercruiser 5.7 / Alpha II - OVERHEAT issue...

[DukesFin]

Okay, the boat: It's a friend's boat and he's asked me for help, so of course, I'm hoping to get it from you folks!

'92 Searay 280 (28')
Twin 5.7 Merc's and Alpha II drives...

The problem:

Port engine is getting overheated when pushed over 3200 RPM.

It's got a new impeller, new water pump and new thermostat.

Cruising around, everything is fine until you try to "push" it over 3200. Temp goes to 170 or 200F. Ease off the throttle and the temp goes right back down to normal.

I'm thinking maybe the flapper in the y-pipe, but thought it would be a VERY good idea to get all of your input...

What other information would be helpful in helping find/diagnose the problem?

Thanks!

 

[xltier]

Re: '92 Mercruiser 5.7 / Alpha II - OVERHEAT issue...

exhaust elbows could be getting clogged.

 

[DukesFin]

Re: '92 Mercruiser 5.7 / Alpha II - OVERHEAT issue...

Any other ideas out there?

(I'm not ignoring the elbow possibility, but would like to try to get more feedback or confirmation...)...

I DO agree though that it seems like it has to be a water/exhaust restriction of some sort...

???

 

[DukesFin]

Re: '92 Mercruiser 5.7 / Alpha II - OVERHEAT issue...

Any other ideas to look at when I'm out there (at the boat) this weekend?

If one doesn't pan out, I'd like to have other options/possibilities to look at instead of waiting one week to try one at a time!

Thanks!