Welcome Visitor! Please take a few seconds and - Joined
- Jun 1, 2001
- Messages
- 7,897
- Age
- 64
- Vehicle Year
- 1987... sorta
- Transmission
- Manual
Ever since switching to my '93 4.0 I have been a bit unhappy with the temp my truck ran at.
But I attributed it to the 195deg T-stat I was running (I normally run a 180deg)
It never really ran "hot" until my most recent recent trip to wyoming over the christmas holiday, but it ran warmer than I was happy with (mid-scale on my '87 guage)
Well on this last trip to wyoming (actually on the way back) it started to get gradually worse, and worse...
Across Iowa it started "Foaming" into the overflow bottle and as I drove further I started to relaize that letting the engine rpm get to 2500rpm let alone exceed it the temp would start rising on the guage. and once I started to see real hills (in western Pennsylvania on I-80) I discoved that I need to keep rpm even lower. (2100ish)
Well this just wasn't right.... particularly in a truck with 4.10's and only 235/75 tires....
I have subsequently replaced BOTH the Thermostat and the radiator. I haven't refilled the coolant or restarted the engine yet.
I'm still reasonably sure that I've got the problem licked, because as I was swapping the radiators I needed to swap over the tranny cooler fittings
(I use the tranny cooler as a P/S cooler) I broke the internal cooler on the radiator being removed.
At that point I decided, "well it's fucked, may as well knock it apart and see what's wrong with it"... well the passenger (hot side) tank was slightly "gooped up" when I got the side tank off of it, but I didn't realize just how bad it was until I tried blowing water through the core....
First, understand that I'm running a two core 4.0 A/T radiator.
This radiator has two rows of 40 (forty) tubes each.
Each tube is 1/8" X 1-1/8"
Of these EIGHTY tubes 56 of them were completely plugged.
Of the remaining 24 (ammounting to 60% of the capacity of
a 4.0 manual trans radiator) approximatly 10 of them were
partially obstructed.
So there is little mystery as to why my engine was "running warm"
And the cold temperatures (single digit temps and highway speeds
for the ride home) are probably the only reason why I didn't
"burn the engine down" though the jury is still out on any
dammage to the engine...
AD
But I attributed it to the 195deg T-stat I was running (I normally run a 180deg)
It never really ran "hot" until my most recent recent trip to wyoming over the christmas holiday, but it ran warmer than I was happy with (mid-scale on my '87 guage)
Well on this last trip to wyoming (actually on the way back) it started to get gradually worse, and worse...
Across Iowa it started "Foaming" into the overflow bottle and as I drove further I started to relaize that letting the engine rpm get to 2500rpm let alone exceed it the temp would start rising on the guage. and once I started to see real hills (in western Pennsylvania on I-80) I discoved that I need to keep rpm even lower. (2100ish)
Well this just wasn't right.... particularly in a truck with 4.10's and only 235/75 tires....
I have subsequently replaced BOTH the Thermostat and the radiator. I haven't refilled the coolant or restarted the engine yet.
I'm still reasonably sure that I've got the problem licked, because as I was swapping the radiators I needed to swap over the tranny cooler fittings
(I use the tranny cooler as a P/S cooler) I broke the internal cooler on the radiator being removed.
At that point I decided, "well it's fucked, may as well knock it apart and see what's wrong with it"... well the passenger (hot side) tank was slightly "gooped up" when I got the side tank off of it, but I didn't realize just how bad it was until I tried blowing water through the core....
First, understand that I'm running a two core 4.0 A/T radiator.
This radiator has two rows of 40 (forty) tubes each.
Each tube is 1/8" X 1-1/8"
Of these EIGHTY tubes 56 of them were completely plugged.
Of the remaining 24 (ammounting to 60% of the capacity of
a 4.0 manual trans radiator) approximatly 10 of them were
partially obstructed.
So there is little mystery as to why my engine was "running warm"
And the cold temperatures (single digit temps and highway speeds
for the ride home) are probably the only reason why I didn't
"burn the engine down" though the jury is still out on any
dammage to the engine...
AD
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