I put a Summit aluminum rad in my Traveler and to make plumbing easier, instead of stock hoses I made 2 1/4" rad inlets and used flex hose that is all the same diameter (stock SII hoses neck down to 2" on the rad from 2 1/4" on the engine). I am also using a 180* Robertshaw stat.

Let me first say I am very happy with the cooling performance so far. This is not a problem, just a curiousity I've been thinking about.

When idling or doing anything low-speed (like wheeling) the temp stays right at 180. Doesn't budge. I have the electric fan set to come on a hair above this so the fan will pop on very briefly and shut right back off again every few minutes or so.

At highway speed, anything higher RPM, it hovers between 185-195. Fan stays on constantly. It never, ever gets above this so like I said this really isn't a problem. I'm just kinda wondering why. If it were a leaky head gasket or cracked head it'd get hotter. Besides, the motor only has about 3000 miles on it.

Here's my thought. Since I opened up the coolant flow a lot in the whole system (wider hoses and inlets, RS stat) I am thinking maybe the coolant doesn't spend enough time in the rad to get cooled as efficiently as when the water pump is spinning slowly at idle RPM.

Would it be worth my time to put a regular parts-store stat in to try and restrict flow a little? Or do you guys who know what you're doing think maybe something else is going on?

Thanks,
Darel

Sounds like it's working perfectly to me. Why mess with it?
If anything turn up the stat on the elec fan so it doesn't run all the time on the road. :)

Mine hit 255 yesterday on the trail, wana trade? :rolleyes:

Yup! Your doing good why worry? Turn the fan thermostat up to 200. amybe wire in an on/off switch to override the thermastat when trail riding so you can run the fan.

There is 111,400 Btus in a gallon of gasoline. Your engine turns this into heat and power. You use more gas in the highway than the trail, hence more heat.

There is 111,400 Btus in a gallon of gasoline. Your engine turns this into heat and power. You use more gas in the highway than the trail, hence more heat.


OS, you are just full of knowledge,probably the wisest sob i know :idea:

Not worried, just curious. I just expected it to run warmer on the trail than the highway. No big deal, thanks!

Darel - it could also be that the electric fan is *restricting* air-flow at highway speeds.

I'm unhappy with my "temp probe in the fins" fan controller.

If I set it so it only comes on over 200deg on the highway, it'll hit 250 while idling.. set it so it comes on at 200 while idling, it runs non-stop on the highway..

Next time I'm going for a screw-in temp probe right into the coolant..

Tom,
That's not it, if I turn the fan off on the highway the temp does slowly climb higher. I need the fan at highway RPM. I tried using a "wet" fan stat but I couldn't get the pipe plug out of the side of the water neck (without damage) so I exchanged it for the fin-probe one. It took me a while to get it set but now that I have stopped playing with it I'm very happy and it always comes on and shuts off right where I want it now.

I've been using the Scout to drive to work lately since my International 444E (otherwise known as a '95 diesel F-250) is down with vacuum pump problems. It's been over 85-90 all week, drivng in Center City traffic, and no trouble whatsoever (except the "curiousity" I mention above) so I've decided to stop questioning it and leave it as-is. Perhaps somewhere down the road I will swap in a non-RS thermostat just out of curiousity but not because I feel the need to.

Thanks!
Darel

How advanced is the timing?

12-15 Btdc.

12-15 Btdc. :shaking:


You need to know what your TOTAL timing is at the RPM it's overheating at. Static, plus centrifugal, plus vacuum advance. You can't assume it's still operating to factory specs. You have to measure it with the proper tools.

Don't roll your eyes at me. Someone just asked how far advanced my timing was. Nine times out of ten this question refers to how far advanced it is at idle. Besdies, it's not overheating.
I'll get the timing light out later tonight.

Darel

:rolleyes: