Another om603 heating thread

[ashedd]

I know I know... there are many topics on the issue. I think my question is a bit unique, to me at least.

After today I have successfully driven 3 diesel MB's from Newport News Va. to my home in Indiana. TomTom takes your right through the appalachian mountains on this trip. Stunning scenery and it get's nice and cool out at the top.

The max grade that I saw via signs were 5% and 7%. The SD did the hills without breaking a sweat and the temp stayed a rock solid 60 degrees. The 190d parts car did the hills at maximum available power output(3rd gear, foot to the floor, 45-50 mph) and never broke the 60 degree mark.

Now we have the 300d with the om603. This car has power, lots of it. It loves the highway, as many of you know. I was charging hard the whole trip and never got below 70mph in the mountains. That means I was doing 70mph on the same grades the 190 was doing 45 wide open. But the 300d(Black Beauty) temp went from it's normal 65 degrees to 100 during the climbs. Pretty much anytime I put a significant load on the engine the temp would rise. It broke 100 once during the trip but NEVER hit the red mark(220 is it?). Once the load/hill was over with the temp would fall pretty quickly back to good ole 65.

So whats the deal? 2 out of 3 cars holds a constant temp and one of them has a aluminum head like the 603. Last week sometime I citric flushed the 300d's cooling system and replaced the thermostat with a new behr replacement. I also added the correct G-05 coolent.

So what needs replaced? Fan clutch? Water pump? Nothing?

I hope you can understand my reluctance in heating my #14 head unnecessarily.

Thanks

PS.

the black beauty has about 140K miles on it.

[Cervan]

blocked radiator, fan clutch is probibally failing too. i absolutely hate clutched fans. when they start to go for me i take some self tapping screws and run 4 of them through the center to make it solid.

[Bio300TDTdriver]

Originally Posted by ashedd

I know I know... there are many topics on the issue. I think my question is a bit unique, to me at least.

After today I have successfully driven 3 diesel MB's from Newport News Va. to my home in Indiana. TomTom takes your right through the appalachian mountains on this trip. Stunning scenery and it get's nice and cool out at the top.

The max grade that I saw via signs were 5% and 7%. The SD did the hills without breaking a sweat and the temp stayed a rock solid 60 degrees. The 190d parts car did the hills at maximum available power output(3rd gear, foot to the floor, 45-50 mph) and never broke the 60 degree mark.

Now we have the 300d with the om603. This car has power, lots of it. It loves the highway, as many of you know. I was charging hard the whole trip and never got below 70mph in the mountains. That means I was doing 70mph on the same grades the 190 was doing 45 wide open. But the 300d(Black Beauty) temp went from it's normal 65 degrees to 100 during the climbs. Pretty much anytime I put a significant load on the engine the temp would rise. It broke 100 once during the trip but NEVER hit the red mark(220 is it?). Once the load/hill was over with the temp would fall pretty quickly back to good ole 65.

So whats the deal? 2 out of 3 cars holds a constant temp and one of them has a aluminum head like the 603. Last week sometime I citric flushed the 300d's cooling system and replaced the thermostat with a new behr replacement. I also added the correct G-05 coolent.

So what needs replaced? Fan clutch? Water pump? Nothing?

I hope you can understand my reluctance in heating my #14 head unnecessarily.

Thanks

PS.

the black beauty has about 140K miles on it.

Nothing!

I don't know about the other 2 cars, but 65 is NOT the normal temperature for an OM603. Did you put in the correct thermostat? Maybe you are miss reading the gauge. Mine runs a tick above 80 which I believe is the normal operating temperature. Some posts say 83. With a new water pump, fan clutch, clean radiator and condenser, mine will go up to 100 or just a touch over. 105 is in the safe range according to the gauge and the conventional wisdom on this site.

Since the thermostat isn't all the way open at 80, how would the car possibly stay right at 80 under any load?

I wouldn't worry about it if it were mine. If you want something to worry about: worry about how our grandkids are going to pay for the ridiculous cash for clunkers program.