Turbine Doc
Just Another Diesel Guy
1st posted 6-27-04
I ran an experiment some time ago now started at Page, transported to Place that I thought worthwhile to post here, new info to some, and a revisit for others.
In Jan 04 I had a FSD "go bad", shut me down on the highway on a return trip from my hunting camp about 2 hours into the 2.5 hr return trip, outside temp was 50F, FSD mounted on a cooler was cool to the touch but would not let the truck start, it had stumbled a couple of times before shutting down, 1 restart then no start. At the time that FSD had about 50K on it, swapped to the new spare I carry and came home. New spare has about 10 K mi on it.
I got home and cleaned up the Bad FSDs transistor mount studs , nuts, to remove any oxidation that might be present, and re-torqued to 10" lb, I slaved it in and truck started right up, it became my spare.
With all the debate it's heat, its loose fasteners, I decided to run an experiment but did not get to it today. Bad FSD reinstalled at 84200, now at 84212mi no problems, will long road test tomorrow.
I took "bad" FSD and; reinstalled it on the cooler, but I 1st filed a small groove in it's base to accommodate a thermocouple wire that touches one of the transistor bases just to see how hot these things actually get and how long will this "bad" one hang in there.
My cooler is mounted on drivers side fender in pocket/bracket where a gassers washer fluid tank goes.
My engine was warm I had been road testing brakes after installing new stainless braided brake lines, I had run it for about 15 minutes. I only have 1 thermocouple so I don't know under-hood temp, ambient air was 80 F.
1st run was 15 minutes with engine at idle, hood down FSD at 96F starting went to 144.8 F in 15 minutes
I shut down the engine for 25 min and temp had dropped to 119.3
I restarted engine and drove for 10 min city traffic 0-50 mph temp varied 135-139
Shut down for another 6 min temp went to 131, restarted and within 4 min 40 sec temp rose to 151.6
Shut down engine after 6 min of driving 0-50 and engine was 150.7
After 42 minutes FSD had cooled to 129.3
After 2 hr 10 minutes FSD was 116 deg
Truck restarted FSD 7min 45 sec 116F up to 133 F 0-50 driving approx 2 miles
shutdown for evening FSD after 30 min back to 118
Will collect more data in AM, I'll also be collecting some numbers on IP PMD location later
I ran an experiment some time ago now started at Page, transported to Place that I thought worthwhile to post here, new info to some, and a revisit for others.
In Jan 04 I had a FSD "go bad", shut me down on the highway on a return trip from my hunting camp about 2 hours into the 2.5 hr return trip, outside temp was 50F, FSD mounted on a cooler was cool to the touch but would not let the truck start, it had stumbled a couple of times before shutting down, 1 restart then no start. At the time that FSD had about 50K on it, swapped to the new spare I carry and came home. New spare has about 10 K mi on it.
I got home and cleaned up the Bad FSDs transistor mount studs , nuts, to remove any oxidation that might be present, and re-torqued to 10" lb, I slaved it in and truck started right up, it became my spare.
With all the debate it's heat, its loose fasteners, I decided to run an experiment but did not get to it today. Bad FSD reinstalled at 84200, now at 84212mi no problems, will long road test tomorrow.
I took "bad" FSD and; reinstalled it on the cooler, but I 1st filed a small groove in it's base to accommodate a thermocouple wire that touches one of the transistor bases just to see how hot these things actually get and how long will this "bad" one hang in there.
My cooler is mounted on drivers side fender in pocket/bracket where a gassers washer fluid tank goes.
My engine was warm I had been road testing brakes after installing new stainless braided brake lines, I had run it for about 15 minutes. I only have 1 thermocouple so I don't know under-hood temp, ambient air was 80 F.
1st run was 15 minutes with engine at idle, hood down FSD at 96F starting went to 144.8 F in 15 minutes
I shut down the engine for 25 min and temp had dropped to 119.3
I restarted engine and drove for 10 min city traffic 0-50 mph temp varied 135-139
Shut down for another 6 min temp went to 131, restarted and within 4 min 40 sec temp rose to 151.6
Shut down engine after 6 min of driving 0-50 and engine was 150.7
After 42 minutes FSD had cooled to 129.3
After 2 hr 10 minutes FSD was 116 deg
Truck restarted FSD 7min 45 sec 116F up to 133 F 0-50 driving approx 2 miles
shutdown for evening FSD after 30 min back to 118
Will collect more data in AM, I'll also be collecting some numbers on IP PMD location later
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