Temperature advice needed on 4.3 mercruiser

[Big Pete]

Hi Guys
I had the boat running for a fair blast , the boat is new to me by the way and my first solo run ..

On start up and idle it sits straight and cool at 140 ish , took her out and gave her a good run on the plane and the temperature goes up to 210 ish , when i slow down back to idle she comes back to 130 ish again .

Is that normal or should i be concerned ?

Forgot to add, Oil Pressure always stays constant sitting minimum half way on gauge ..

 

[joedee983]

Re: Temperature advice needed on 4.3 mercruiser

I had a similar problem with my 4.3. It turned out to be a kinked water hose in the drive. It got enough cooling water up to about 2500 RPM after that it started to overheat.

 

[cr2k]

Re: Temperature advice needed on 4.3 mercruiser

Sounds like you need an impeller. Always something you should replace when you get a boat and have no history.

 

[Bondo]

Re: Temperature advice needed on 4.3 mercruiser

Sounds like you need an impeller. Always something you should replace when you get a boat and have no history.

Ayuh,... I completely Agree...

 

[ENSIGN]

Re: Temperature advice needed on 4.3 mercruiser

Ditto

 

[spect8r]

Re: Temperature advice needed on 4.3 mercruiser

Yep, definitely the impeller. Easy fix.

 

[Big Pete]

Re: Temperature advice needed on 4.3 mercruiser

Thanks guys..

I thought that would be the case , but not knowing how these bigger engines run i wasnt sure. also our sea temperature is around 28c here so wondered if it was maybe possibly acceptable.

I am pretty annoyed as part of the deal with buying this boat was full service included , and to my reckoning impellers are part of a main service..

So i spoke with the dealer around 11.00am this morning and she was also not impressed and agreed should have been done !!!

She made a list of all my other very minor bits i was not happy with. She made 1 phone call and by 12.00pm the boat is out of the water and in there service area on blocks , and will have it all sorted by Wednesday morning ..

So i cant moan at that can i ?

Will see if it cures the problem as apart from that i love the boat

 

[Big Pete]

Re: Temperature advice needed on 4.3 mercruiser

Update..
They had put new impellor in ,, but didnt rinse it through ? Stripped it and washed out a lot of crud and now so far all is now ok..

Time will tell as i havent been out for a long run yet .. It was steady on the quick 20 minute run so fingers crossed ..

 

[sethjon]

Re: Temperature advice needed on 4.3 mercruiser

You should be very concerned. In fact, if the temp gauge is even close to correct you should it down immediately. The first thing to check is the t-stat. After that check to see that water is flowing through the system.