Driving without a fan belt.
 

Hi

I was driving the 240D on the freeway last Friday, when suddenly the alternator bearings froze up and shredded my fan belt.
I kept driving at about 65 mph, expecting the engine to overheat soon.
To my surprise the temperature only rose to about 95° C.
So I kept driving for 50 Miles until I hit Las Vegas city traffic and had to slow down.
Then at once the temperature climbed to 110° C and I had to shut the engine of.

At a speed of about 60 mph there is enough air flow through the radiator to spin the fan and the water pump fast enough to keep the engine temperature in acceptable limits.

I also found that the heater didn't work.
The water pump didn't spin fast enough to force the coolant through the heater core.

Nice to know that you can drive this old Diesels without a fan belt, as long as you drive fast enough.

Amazing. That means they don't technically need electricity OR belts to run :D

EMP Attack Approved for sure! :D

I have a feeling that would not work on the 5 cylinders, the heat production is quite a bit higher....especially on the turbo engines.

Yeah wouldn't work on a 300D, only on the 240D because they don't have a fan clutch.

That problem could be solved with a shoe lace.

I don't think the clutch is the reason it wouldn't work on a turbo motor... I think it's the MASSIVE amount of heat the motor produces pushing the taller diff.

LV is pretty flat too, so the 240 cruising at 60 on flat ground likely has little heat produced.
the reason you had no heat was the WP was not turning much if any at all.
actually, I think the wp would be turning backwards without the motor. the heat likely was moving thermally, not the wp pushing it.

yeah, but velcro shoes are cool...:cool:

I actually doubt a 617 turbo would be making all that much more heat in the same conditions, it would be getting within 2-3mpg of the 240.....so thats a minimal amount more fuel so not that much more heat. However, I bet its enough that it would eventually overheat. The 240 operates below that tipping point.

Ambient air temp would play a role also.

Doesn't the auxilliary pump push any coolant thru the heater core without the water pump?

It would....but its not all that strong, I bet it would have minimal flow-effect with the main pump being non-operational.....never know though, might be just enough to keep the temp out of the red zone depending on ambient temp etc...

It would also stop working once the battery was toasted in this scenario.

I think this is an example of ram air effect.

At 60 mph (+) you have lots of nice air pushing its way into the engine compartment.

At lower road speeds you need your water pump.

I'm glad you posted this 1960mog - yet another nail in the coffin of the "don't remove your mechanical fan" crew.

Not so.
I am running a 300D 6 blade fan and fan clutch in my 240.

The old 240 D's don't have a auxiliary pump.

If the engine is warm enough to need cooling the fan clutch should engage I would think. also the air passively turning the fan would still turn it the same direction, I believe.

Agreed, that would make a ton of noise/impede air flow/cause engine drag if when the engine was moving the fan it was opposite to what the natural air stream was trying to do.

I'm not sure about this.

Correct me if i'm wrong but I don't think it's any additional effort so much as the turbo itself which is producing the extra heat.....

I think the 617 NA could pull this off as well. I've seen my temperature plummet when going downhill in gear when all is well.