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I have read through the threads but I'm at a loss as to why my favorite vehicle is overheating. I'm hoping for some good feedback so please sit back and enjoy the misshaps of Ajaxx (that's me) and his Ambulance (that's the patient).
A few weeks back I made a trip from So. Cal to Las Vegas and when I went over the huge grade outside of Baker, CA I overheated 3 times. I never let it peg out on the temp gauge but would pull over when it got to 3/4 hot and let it boil over and cool off. Then I would add water and I'd be ok for another 15 to 20 miles. Once I got over the grade, my overheating problems were over as it only seemed to overheat while climbing a grade.
In fact, while in Las Vegas, I'd leave the engine idling and crawl into the back for a good nights sleep with the A/C running throughout the night. After 10 continuous hours of that for 5 nights, the temp gauge never climbed beyond 1/3 of the way, which has been the normal temp for this truck for the entire 6 years that I've owned it.
While in Las Vegas I found a mechanic who was not a diesel mechanic but he did find that it had a bad fan clutch. I am pretty sure it was bad because my truck never had that fluctuating fan speed like it does now. It almost sounds like a jet engine when the truck is really under a load or going up a hill. However, this apparently did not fix my overheating problem because on the way back home I still over heated 3 times.
When I got home I Googled my problem and did a lot of research. I even Talked with a retired Ford mechanic. The info I found was that it could be a head gasket but doubtful. I was told iit could need the oil cooler flushed but I couldn't find a local shop that would do it.
I was also told that I may just need to flush out the radiator. I did the flush and everything came out very clean I then filled it with the correct ratio of coolant and distilled water. I even added 16 ounces of the recommended Ford radiator additive which apparently has something to do with electrolites and protecting the cylinder walls. Maybe a Gatoraid for Ford diesels.
It was also suggested that I powerwash through the radiator coils and I did that too. And as a final step I replaced the cap on the degas tank as recommended.
Around town it was now running great with no heat issues. A/C still worked great too as it always did. So now it was time for the true test and try another trip to Las Vegas.
It just so happened that my new Vegas trip was beginning on one of So. Cal's hottest days of the year. It was a dIsaster. I didn't even make it to the steep long grade outside of Baker, CA. I didn't even make it even up the grade leading into Victorville, CA (which is about 80 miles away). The temp gauge went past half way just going over the 241 toll road leading to the 91 freeway which is a hilly climb but only 3 or 4 miles in distance. On the grade 26 mile before I got to Victorville I decided to turn around and limp it back home. Total amount of times that I needed to pull over before the temp gauge pegged out was 6 times but I never let it boil over until the last time.
Also I have to tell you that the truck was empty weight but just that 162 mile trip burned a total of 19 1/2 gallons of fuel which is the worst mileage (8.3 mpg) I have ever gotten.
About 3 miles befpre I finally got home I noticed a noise under the hood that sounded almost like a belt issue. Also I forgot to mention that 1/2 way back home, the a/c stopped blowing consistantly cold air (this was now at night and the outside temp was in the low 70's). I shut down the a/c and tried it again a little while later and it no longer produced any cold air at all.
When I finally got home I popped the hood and found smoke coming from around the a/c compressor. The belt was fine although it was hot and very very tight with absolutely no play in it. The belt did have the required 1/2 inch play but now there was no play at all. I'm not sure if the heat caused it to tighten up or if the mechanic that replaced the fan clutch did not adjust it correctly.
After the smoke subsided, I restarted the truck and noticed that the a/c fan clutch and pully assembly were frozen completely. The belt was just dragging across the stuck pulley hence the source of the smoke. The clutch and pully were very very hot. I shut the engine down and let it cool down completely (about 3 hours).
I restarted the engine and everything appeared to be working fine including the a/c pulley and clutch. I decided to turn on the a/c and see if it would work now. It was blowing lots of cold air but I did notice that the compressor clutch would engage and run for about 10 seconds and then disengage for about 10 seconds. It did this continuously. Not sure but I don't think this should be happening.
So here's my thoughts. Could my problem have been this a/c clutch/pulley assembly all along or is this just another problem popping up? Was the way too tight belt my problem? I think the stuck pulley could explain the poor fuel mileage but I'm not a mechanic. Maybe I have more than one problem now.
For weeks I have been trying to get a mechanic to look at it but the only one I can find here in town (San Clemente) wants about $155 an hour for labor and at that price I could not afford much. I really need an accurate diagnosis though, just not at that price. Does anyone in the area know of a good honest affordable deisel mechanic I could have take a look at it?
Radiator flushes and replacing the thermo are all within my abilities but detailed repairs or figuring out the problem seem to be over my head. Any insight or help you can offer is greatly appreciated.
Thanks a lot and sorry for the long post but I wanted you to undertand exactly how my baby has been acting.
I don't know if this makes a difference but about 6 months ago I switched to synthetic oil. Also the thermostat was replaced with a 195 degree thermostat when the fan clutch was replaced.
I Love this truck, just need a good diagnosis and a good doctor.
Ajaxx
Truck Details
96 Ford F-350
7.3 diesel,
Automatic with overdrive.
Body style: Ambulance
Miles: 131k
bought it at 105k, owned for 6 years
Oil: 14 1/2 qts synthetic oil and filter once a year.
Coolant capacity according to the Ford Service manual 23.5 qts. However whe I did the radiator flush it only took 17.5 qts.
Additional: I Always use Lucas diesel additive as recommended by several commercial truck drivers.
A few weeks back I made a trip from So. Cal to Las Vegas and when I went over the huge grade outside of Baker, CA I overheated 3 times. I never let it peg out on the temp gauge but would pull over when it got to 3/4 hot and let it boil over and cool off. Then I would add water and I'd be ok for another 15 to 20 miles. Once I got over the grade, my overheating problems were over as it only seemed to overheat while climbing a grade.
In fact, while in Las Vegas, I'd leave the engine idling and crawl into the back for a good nights sleep with the A/C running throughout the night. After 10 continuous hours of that for 5 nights, the temp gauge never climbed beyond 1/3 of the way, which has been the normal temp for this truck for the entire 6 years that I've owned it.
While in Las Vegas I found a mechanic who was not a diesel mechanic but he did find that it had a bad fan clutch. I am pretty sure it was bad because my truck never had that fluctuating fan speed like it does now. It almost sounds like a jet engine when the truck is really under a load or going up a hill. However, this apparently did not fix my overheating problem because on the way back home I still over heated 3 times.
When I got home I Googled my problem and did a lot of research. I even Talked with a retired Ford mechanic. The info I found was that it could be a head gasket but doubtful. I was told iit could need the oil cooler flushed but I couldn't find a local shop that would do it.
I was also told that I may just need to flush out the radiator. I did the flush and everything came out very clean I then filled it with the correct ratio of coolant and distilled water. I even added 16 ounces of the recommended Ford radiator additive which apparently has something to do with electrolites and protecting the cylinder walls. Maybe a Gatoraid for Ford diesels.
It was also suggested that I powerwash through the radiator coils and I did that too. And as a final step I replaced the cap on the degas tank as recommended.
Around town it was now running great with no heat issues. A/C still worked great too as it always did. So now it was time for the true test and try another trip to Las Vegas.
It just so happened that my new Vegas trip was beginning on one of So. Cal's hottest days of the year. It was a dIsaster. I didn't even make it to the steep long grade outside of Baker, CA. I didn't even make it even up the grade leading into Victorville, CA (which is about 80 miles away). The temp gauge went past half way just going over the 241 toll road leading to the 91 freeway which is a hilly climb but only 3 or 4 miles in distance. On the grade 26 mile before I got to Victorville I decided to turn around and limp it back home. Total amount of times that I needed to pull over before the temp gauge pegged out was 6 times but I never let it boil over until the last time.
Also I have to tell you that the truck was empty weight but just that 162 mile trip burned a total of 19 1/2 gallons of fuel which is the worst mileage (8.3 mpg) I have ever gotten.
About 3 miles befpre I finally got home I noticed a noise under the hood that sounded almost like a belt issue. Also I forgot to mention that 1/2 way back home, the a/c stopped blowing consistantly cold air (this was now at night and the outside temp was in the low 70's). I shut down the a/c and tried it again a little while later and it no longer produced any cold air at all.
When I finally got home I popped the hood and found smoke coming from around the a/c compressor. The belt was fine although it was hot and very very tight with absolutely no play in it. The belt did have the required 1/2 inch play but now there was no play at all. I'm not sure if the heat caused it to tighten up or if the mechanic that replaced the fan clutch did not adjust it correctly.
After the smoke subsided, I restarted the truck and noticed that the a/c fan clutch and pully assembly were frozen completely. The belt was just dragging across the stuck pulley hence the source of the smoke. The clutch and pully were very very hot. I shut the engine down and let it cool down completely (about 3 hours).
I restarted the engine and everything appeared to be working fine including the a/c pulley and clutch. I decided to turn on the a/c and see if it would work now. It was blowing lots of cold air but I did notice that the compressor clutch would engage and run for about 10 seconds and then disengage for about 10 seconds. It did this continuously. Not sure but I don't think this should be happening.
So here's my thoughts. Could my problem have been this a/c clutch/pulley assembly all along or is this just another problem popping up? Was the way too tight belt my problem? I think the stuck pulley could explain the poor fuel mileage but I'm not a mechanic. Maybe I have more than one problem now.
For weeks I have been trying to get a mechanic to look at it but the only one I can find here in town (San Clemente) wants about $155 an hour for labor and at that price I could not afford much. I really need an accurate diagnosis though, just not at that price. Does anyone in the area know of a good honest affordable deisel mechanic I could have take a look at it?
Radiator flushes and replacing the thermo are all within my abilities but detailed repairs or figuring out the problem seem to be over my head. Any insight or help you can offer is greatly appreciated.
Thanks a lot and sorry for the long post but I wanted you to undertand exactly how my baby has been acting.
I don't know if this makes a difference but about 6 months ago I switched to synthetic oil. Also the thermostat was replaced with a 195 degree thermostat when the fan clutch was replaced.
I Love this truck, just need a good diagnosis and a good doctor.
Ajaxx
Truck Details
96 Ford F-350
7.3 diesel,
Automatic with overdrive.
Body style: Ambulance
Miles: 131k
bought it at 105k, owned for 6 years
Oil: 14 1/2 qts synthetic oil and filter once a year.
Coolant capacity according to the Ford Service manual 23.5 qts. However whe I did the radiator flush it only took 17.5 qts.
Additional: I Always use Lucas diesel additive as recommended by several commercial truck drivers.
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