Ford 302 rapid temperature rise at idle

[DAVID GAGNARD]

Originally Posted by UKjohnnycobra

Thanks again, all. It may be a couple of days before I can test these ideas and post pics as I will be travelling for a couple of days. I'll bump this thread later.

If you have NO fan shroud at all, that is 95% of your problem.......at speed, air is forced thru the radiator, at idle,only the fans will pull air thru the radiator and without a shroud, they are operating at maybe 50% capacity......

Your pulley sizes are fine,being it runs at the temp it does on at speed, tells me your cooling system is fine....you just don't enough air coming thru at idle without a shrouded fan........

at idle,get out of the car, light a cigarette, put it in front of the radiator and see how much smoke is pulled thru, then put it on the side of the radiator and see how much smoke is going around the radiator instead of thru it, you may be suprised.....the fans will pull the air from on the path of the least resistance, which without a good fitting shroud, it will come from around the raditor instead of thru it.......
David