Temp on my Yanmar 1500

EFC · May 30, 2003

The reason it cools down when you run it at higher RPM is because it has more HP at higher RPM. Your PTO hp is rated at 2400 RPM, below that it drops of significantly. I tested a yanmar 1401 and at 2400 RPM it had 15.1hp at the PTO. at 2000 RPM it had 8hp. I know it seems like it is going to fly apart but runnig a tractor at an RPM that it is not rated for does far more damage long term

allenp · May 30, 2003

Maybe I wasn't clear, my 1700 runs cooler at 2000-2200 than it does at full throttle (2400). It may be a fluke or just in my mind, but the engine temp seems to run at least 10 degress less at 2200 than it does at 2400.

normde2001 · May 30, 2003

Have your rad. cleaned by a rad. shop, reinstall, flush system,
problem solved.

machinefarm · Jun 1, 2003

RDAM, "Water Wetter" works great. I drag raced in the NHRA division 7 for several years. My home track was Firebird Raceway in Phoenix, AZ. Most of the guys I know ran distilled water with the Red Line company's "water Wetter" product. It did help high performance engines run cooler in the desert. When racers use the product in the heat, it should be a good endorsement for it's effectiveness. Red Line does not reccommend the use of ANY coolant wqith the product, only water. I have not used it in my 1602D because I am now living in Minnesota and don't have any overheating problems no matter how hard I work the Yanmar.

Jim, Machinefarmer

Anonymous Poster · Jun 3, 2003

Does anti-freeze raise the boiling temp? I didn't realize that? I thought that was purely a function of the pressurized system. I was aware of lubricants and rust prohibitors. However, I think you can buy a rust prohibitor by itself.

As the name suggests, it clearly LOWERS the freezing temp

Anonymous Poster · Jun 3, 2003

All antifreeze both raises the boiling temperature and lowers the freezing temperature by putting particles in between the water molecules. We use light weight molecules suchas salt on the roads (which would of course corrode engines) or ethylene glycol in engines). The change in boiling/freezing point is proportional to the number of particles added per unit volume (i.e. the more you add, the more the temperature changes at which you can freeze/boil the water).