Volvo 151/290's Running temps?

[hanjae]

Volvo 151/290\'s Running temps?

Took my Triana out for a good run yesterday, the first time ever! More adventurous that the numerous runs from the boatyard to the mooring trying to get her running OK!
My main concern is the running temps on both engines under load appears to be at the top end of the dials, about 1/8th inch from the red. The starboard sometimes is just slightly lower but that has the hot water immersion tank on it. Both engines have new water pumps, the freshwater header tanks are working correctly with no blow off through the pressure caps, I have completely cleaned both systems with Rydlyme, this cleaned the header tanks out beautifully so it must have done a lot for the rest!
My only option is to take out the thermostats, is this advisable. They are in good condition and opened properly when I tested them in a saucepan!



What else can I do? /forums/images/graemlins/confused.gif

 

[spannerman]

Re: Volvo 151/290\'s Running temps?

I have had a few instances where people have tested their stats in a saucepan and said 'yes they open OK' and have gone on to change lots of other components in the system. But they didn't check at what temp they opened, this must be checked with a thermometer and should correspond to the temp stamped on the stat itself.
If they are working correctly, check the exhaust bend to see if it gets too hot to touch, on these engines they tend to rust and block the holes where the seawater enters the exhaust, so you may have a good raw water pressure but it can't get out so the temp goes up due to slow circulation on the raw water side. The other item to check is the oil cooler, as this can be restricted in flow also, anything that inhibits the raw water circulation is going to cause overheating.