still overheating what else?

[northvanwatertaxi]

Hello thanks to everyone that helped, I'm still having problems with my fwc 302 ford engine with pre alpha merc drive.
It runs fine at idle, but at cruising it still overheats.
The raw water pump is new and working great.
so is the thermostat. tested it in water
manifolds clear so are risers they are ok to touch
temp is 130 at idle and will run fine at 1000 rpms
haave back flushed engine with circulating pump off
there is no water in drive oil or engine
has tons of power and engine sounds good
any idea what else to check?

 

[Bt Doctur]

Re: still overheating what else?

water pump base gasket sucking hot exaust, copper coupler tube has corroded hole thru it, water pocket cover leak,damaged coupler hose (gimbal to transom) kinked/collapsed internally,leaky had gasket blowing hot exaust into the system.

 

[calwldlif]

Re: still overheating what else?

Might be time to look for cracks
head gaskets.
Compression check.
Since you have closed cooling
you can check for exhaust gases,
bubbles or died paper check will reveal presence
of exhaust gases.(there are litmus type papers
you dip in cooling water) I think there are
liquid type tests, drop in coolant and look for
color change.
Do you have a coolant recovery bottle?
does it loose coolant?
Bummer man!!!:%

 

[northvanwatertaxi]

Re: still overheating what else?

yikes! ok thanks I will check compression, plugs
coolant bottle, coolant test. I really appreciate the leads. the transom assembly was just replaced and is a good used one, the leg has been taken out and tested. I will check the risers to see if they are getting hot next time i'm out , that should eliminate the raw water system.
If it is the head gasket I guess it would make sense to at least check the heads out. and clean carbon, I wouldn't mind re-powering because this engine was used (cost me$1000) about 5 years ago and i'm sure I could find another one that is gtg maybe something newer?

 

[Blk-n-Blu]

Re: still overheating what else?

Howbout inline coolers ( oil, power steering) or this:
http://www.sterndrives.com/overheating_highspeed.html

 

[Haut Medoc]

Re: still overheating what else?

I forget, his is a closed system, no?
I remember your posts somewhat....
It is too hard to look back with the new search function, so let's start there.....JK

 

[northvanwatertaxi]

Re: still overheating what else?

Hi Haut, yes it's fresh water cooled. How is your boat running? I remember you were having almost the same problem.

 

[Haut Medoc]

Re: still overheating what else?

No, I had that problem in the past.....
It was the closed part of the heat exchanger, clogged with crap, that reduced it's efficientcy @ high speed....
My boat is running very well, thank you!......JK.....