yamaha 240 hp

[tonka]

looking for the running temp of the 240 hp diesel ,seems to sit quite high when under load .about 90 degrees/

[Sharky]

90 to 94c is about right for diesel engines. If it is running cool when not under load, check the thermostat

[tonka]

thanks for the answer sharky, thought it was a little bit hot at 90 but feel better now cheers.

[JIY]

I run a YANMAR 250hp on my Tornado - once it warms up the guage always reads amost exactly 90 degrees.

[tonka]

thanks for the answer jiy some people have been telling me that the yamaha 240 hp should run at between 80 to 85 degrees this one sits on 90 so i thought i might have a cooling problem,

[Jelly]

Tonka
I have the 165 Yam and when running it sits about or just below the 90 degree mark.
If you find that it suddenly overheats when you up the revs to over 3/4 throttle (as we did) check the hose that connects the raw water from the leg to the transom sheild, it had come off on ours and we only found it when it was pulled out of the water. (mercrusier pipe clips fit the hose and hold better so the engineer told us).
I've got the workshop manuals for the leg and the 165 if thats of help drop me a pm.
Jelly

[tonka]

thanks jelly will let you know once i have a look at the drives.

[hamadi]

my 421 stip run at 80-90 degrees celcius even with 30 degrees seawater.
Seawater impeller should be inspected before boating season and changed every 2-4 years. Engine temperature rising abnormally when throttle is 3/4 to 4/4 is often caused by loose belt (raw water pump) or clogged mixing elbow. I had this problem yesterday and cleaned the elbow water passages (4) with a rod after soaking in oxalic acid.