- City
- Olathe
- State
- KS
Louvers, etc. should be used for dissipating heat on the trail... not the road. If your engine's running hot at 40+ mph, you've got "internal" (timing, radiator, flow) issues.
How do you identify which of these 3 you have?

Louvers, etc. should be used for dissipating heat on the trail... not the road. If your engine's running hot at 40+ mph, you've got "internal" (timing, radiator, flow) issues.
Fine around town, and on the trail. Builds heat on hwy.
Could your carb be running lean, that would creat additional heat (right after you get off the highway, check you're plugs to see if their bone white). Advanced timing could cause this also. You're electric fans, can they be restrictive at freeway speed. This would cut down the air flow through the radiator (the advantage of having a mechanical clutch fan).
Take the winch off of the Jeep and run it too. I'll bet that will shave off quite a bit of the temperature too.

How old is the radiator?
If not running lean, check the timing. If base timing is ok, try disconnecting the vacuume advance. That would leave mechanical and centrifugal advance. Now take her on the freeway and check the temp. You have a new radiator, so the next question is did you replace the lower hose. If it doesn't have a spring in it, could it be collapsing from the suction of the pump. Try squeezing the hose to see how stiff it is (sounds silly but it has happened before).
There is base, mechanical, vacuum, and total timing.