Mirage 28 Intermittent Engine Overheat Probs

[Guest]

Can anybody help please?
I have a 1981 Mirage 28 with a Yanmar 2QM15 engine.
For the last few weeks I have been exp probs with intermittent overheat problems which manifest itself by lack of water through the exaust and the audible engine alarm comming on from time to time. This problem seems to happen when the boat is in rough conditions and slamming or if I am going astern (which I have to do to get into my mooring).
I have replaced the impeller now twice and also changed the thermostat.
I am worried that the overheat will eventully cook the engine. I am running out of ideas and can not just replace evey componant on the engine! (much to the disapointment of the engine dealer!!!)
If any body can help, please post replies.
Thanks and regards,
RodC

 

[david_bagshaw]

If the water flow from the exhaust is reduced when slamming / going astern

My suggestion would be to look for air getting into the suction side either at the pump or the plumbing from the skinfitting to the pump, & thus the pump losing its prime and output being reduced for a time.

Has this always happened or recently started?

is there some obstruction in the plumbing that causes an intermittant blockage?

David psTake a look at www.yachtman.co.uk

 

[Guest]

Sounds like problem with the water inlet. Partly blocked?

 

[Guest]

Waterinlet has been checked and is clear!

 

[Guest]

I bought the boat 1 year ago at that stage this problem was not there as far as I could see. Since I serviced the engine 3 weeks ago this problem has apeared.
RodC