overheating

9rock · Post by **9rock** » Sun Jan 09, 2011 6:55 pm

well my first season of a Trojan owner rapped up last week when I moved my boat to its next years home, the ride was about 15 m ,
After about 3 miles cruising at 2500 rpms 17 mph the starboard engine started to creep up we backed it down when it hit 190 to 2000 9 mph

when it reached 160 after a short while we dialed it back up and again it did the same thing,,

I had had this engine overheat and found out the thermostat was stuck and replaced it , also I noticed I may be losing a little ati freeze .

just looking for a place to start

Other than that I really enjoyed my Trojan just a few hiccups that u would expect from a 3500 dollar 33yr boat , but all in all I love it and look forward to more boating next year

9

rbcool · Post by **rbcool** » Sun Jan 09, 2011 7:20 pm

Sounds like risers/manifolds

Ron

prowlersfish · Post by **prowlersfish** » Sun Jan 09, 2011 9:11 pm

You can use a radiator pressure tester to test for coolant leaks . Boats for sale tend to sit so you may want to check the thru-hulls for growth also growth on the running gear can add more load to the boat making the engines work harder

Did the temps remain normal after replacing the thermostat ?

Peter · Post by **Peter** » Mon Jan 10, 2011 10:21 am

Not too state the way too obvious,but check the impeller as well.If you loose a couple of rubber vanes off of it, temps will do as you describe.

rbcool · Post by **rbcool** » Mon Jan 10, 2011 10:50 am

Peter wrote:Not too state the way too obvious,but check the impeller as well.If you loose a couple of rubber vanes off of it, temps will do as you describe.

Good one

And a lot easier to check than a manifold!!!!!

Ron

Big D · Post by **Big D** » Mon Jan 10, 2011 9:30 pm

I agree with all the above. I'd check the easy stuff first before taking apart major hardware. Yes check the impeller; if vanes are missing, you must find them. They may be stuck in the oil cooler or heat exchanger and restricting flow. If all the vanes are there, make sure they have not taken a set in a bent position. This will reduce flow as well.

Make sure there are no collapsed or kinked hoses. Check right from the through hull to the engine and so on. Also check to ensure all hose clamps are tight so you don't draw air into the system.

Check your heat exchanger. If it has a removable end plate, remove it to check the insides. It may be clogged and not dissipating heat properly. You may need a gasket to reinstall the plate.

Need more info as well about your application; what kind of engine do you have, v-drives or not, etc. more info is good, helps us help you.

lakeguy72 · Post by **lakeguy72** » Mon Jan 10, 2011 11:21 pm

I had this problem several years ago and I also was losing antifreeze. I replaced the heat exchanger cap and the problem went away. If it's a raw water cooled engine I'd check the other items mentioned.
Lakeguy

9rock · Post by **9rock** » Tue Jan 11, 2011 9:03 pm

Big D wrote:I agree with all the above. I'd check the easy stuff first before taking apart major hardware. Yes check the impeller; if vanes are missing, you must find them. They may be stuck in the oil cooler or heat exchanger and restricting flow. If all the vanes are there, make sure they have not taken a set in a bent position. This will reduce flow as well.

Make sure there are no collapsed or kinked hoses. Check right from the through hull to the engine and so on. Also check to ensure all hose clamps are tight so you don't draw air into the system.

Check your heat exchanger. If it has a removable end plate, remove it to check the insides. It may be clogged and not dissipating heat properly. You may need a gasket to reinstall the plate.

Need more info as well about your application; what kind of engine do you have, v-drives or not, etc. more info is good, helps us help you.

Thanks for the help
360 275hp velvet drive , it has closed cooling engine the one that does the manifolds too ,

I have checked all the obvious stuff , I will do a presure test in the spring and look for a leak . I might tear off the heads of the other motor and do valve seals because it smokes a little when u start it so I hope manifolds are ok but now would be the time to do it

9

vabeach1234 · Post by **vabeach1234** » Tue Jan 11, 2011 10:32 pm

Make sure you check the oil cooler on the Transmission as well. If you picked up some seaweed or trash you could have a blockage. They are easy to back flush.

prowlersfish · Post by **prowlersfish** » Wed Jan 12, 2011 6:41 am

They way I read it is the over heating was fixed but he has a coolant leak .

Stripermann2 · Post by **Stripermann2** » Wed Jan 12, 2011 2:40 pm

prowlersfish wrote:They way I read it is the over heating was fixed but he has a coolant leak .

I read his post as it overheats now and that he previously had a thermostat issue which has since been corrected.

No mention of sea strainers...if not, be sure to check seacock for barnicle growth or other build-up reducing flow. You may have what appears to be good flow but once the demand and under load calls for flow, you won't have enough.

9rock · Post by **9rock** » Wed Jan 12, 2011 6:42 pm

Stripermann2 wrote:
prowlersfish wrote:They way I read it is the over heating was fixed but he has a coolant leak .
I read his post as it overheats now and that he previously had a thermostat issue which has since been corrected.

No mention of sea strainers...if not, be sure to check seacock for barnicle growth or other build-up reducing flow. You may have what appears to be good flow but once the demand and under load calls for flow, you won't have enough.

yes that would be correct I fixed the thermastat problam

the seawater flow would explain the rise in temp but not the leaking antifreez ,, I know from my last inboard closed system that just a little loss of fluid will cause temp rise, so I believe find leak and problam will lie there

9

Trojan Boat Forum

overheating

overheating

Overheating