All great ideas and thoughts by all.
In order:
1- get the cheap HF temp sensor then you can verify that it's getting hot and WHERE it's reading hot. Top of the radiator should be hotter than the bottom etc.
2- you have to narrow things down before buying parts and I know this is what you're trying to do
3- I mentioned airflow before even tho someone said they use that fan successfully. Like Broncobowsher said, we all know that at appr 45 mph that the air being forced thru the radiator from travelling is more cfm than what the engine fan can usually move. This is why you are fine when cruising.
4- We "know" that the engine is cooling ok when cruising at highway speeds correct? If this is true then we almost have to admit that the t-stat is opening, the water pump is pumping correctly (and the right direction), that the hoses don't have air trapped in them and blocking flow, etc, etc.
5- since we are hearing that it is low speed heating issues only (correct us if wrong) then the lack of adequate air flow (edit: also caused by no or inadequate shroud) to cool is the culprit. New engines do generate more heat but it is rare that a stock 302 can't be cooled with a stock mechanical fan even without a shroud when just cruising at 10-25mph. My last stroker (last year) was generating 670deg primary header temps. 500 miles later the exact locations were down at 525F.
Easiest and cheapest fix if there aren't any other issues is to install a stock OE 7 blade mechanical fan with a good fitting stock or aftermarket fan shroud and your cooling problems will go away. There is no comparison in air flow between the OE 7 blade fan and the "looks nice but doesn't flow enough Derale electric fan" you are currently running. This is much easier than upgrading to an Explorer clutch type fan/frt dress.
All signs point to air flow now that you showed us some pics, verified that the wtr pump and radiator are new and shouldn't be plugged or not working.
The stock mechanical fan and shroud are VERY cheap compared to going with a newer style fan from late model Mercedes or Camaros that pull enough air to keep an electric fan on your build. The Tauras/Volvo fan works dang good but getting hard to find (unless you buy a new one??) but they pull a lot of amperage and will probably require fabbing a mount for it and new relay to handle the 60amps of draw (or close and that's why the new MB and GM fans are so great). With the correct fan/shroud combo it doesn't matter if you have 2 coolers in front of the radiator (like OE stacks them in), it will pull all the air needed to cool your engine. All the radiator shops say the same thing- properly setup fans/shrouds won't have any issues pulling air thru ac condensors and tranny coolers in front of radiators.
Good luck and report back. Nice Bronco!
In order:
1- get the cheap HF temp sensor then you can verify that it's getting hot and WHERE it's reading hot. Top of the radiator should be hotter than the bottom etc.
2- you have to narrow things down before buying parts and I know this is what you're trying to do
3- I mentioned airflow before even tho someone said they use that fan successfully. Like Broncobowsher said, we all know that at appr 45 mph that the air being forced thru the radiator from travelling is more cfm than what the engine fan can usually move. This is why you are fine when cruising.
4- We "know" that the engine is cooling ok when cruising at highway speeds correct? If this is true then we almost have to admit that the t-stat is opening, the water pump is pumping correctly (and the right direction), that the hoses don't have air trapped in them and blocking flow, etc, etc.
5- since we are hearing that it is low speed heating issues only (correct us if wrong) then the lack of adequate air flow (edit: also caused by no or inadequate shroud) to cool is the culprit. New engines do generate more heat but it is rare that a stock 302 can't be cooled with a stock mechanical fan even without a shroud when just cruising at 10-25mph. My last stroker (last year) was generating 670deg primary header temps. 500 miles later the exact locations were down at 525F.
Easiest and cheapest fix if there aren't any other issues is to install a stock OE 7 blade mechanical fan with a good fitting stock or aftermarket fan shroud and your cooling problems will go away. There is no comparison in air flow between the OE 7 blade fan and the "looks nice but doesn't flow enough Derale electric fan" you are currently running. This is much easier than upgrading to an Explorer clutch type fan/frt dress.
All signs point to air flow now that you showed us some pics, verified that the wtr pump and radiator are new and shouldn't be plugged or not working.
The stock mechanical fan and shroud are VERY cheap compared to going with a newer style fan from late model Mercedes or Camaros that pull enough air to keep an electric fan on your build. The Tauras/Volvo fan works dang good but getting hard to find (unless you buy a new one??) but they pull a lot of amperage and will probably require fabbing a mount for it and new relay to handle the 60amps of draw (or close and that's why the new MB and GM fans are so great). With the correct fan/shroud combo it doesn't matter if you have 2 coolers in front of the radiator (like OE stacks them in), it will pull all the air needed to cool your engine. All the radiator shops say the same thing- properly setup fans/shrouds won't have any issues pulling air thru ac condensors and tranny coolers in front of radiators.
Good luck and report back. Nice Bronco!
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. The outside temp was only about 40. It got up to 232 by 20ish minutes and I stopped the engine then. Not sure if you can see it by the battery, but there is a high and low setting for the fan. That’s what I’ve got for today! Does any of this mean anything??
