Question: best fuel temp
- Thread starter lotsofmiles
- Start date
sure if i get it back. its in the body shop for a problem with my passenger side. someone hit me in the side ran stop sign. needs rear dually fender and both passenger side doors. and a rear cab corner up to back window. then the driver side a rear dually fender hit something on that side too dont know what, but was there when i saw it a few days later after getting better.
Why not just take a piece of pipe and wrap it around the ac accumulator and connect it between the filter and CP3?
Where was the factory fuel temp sensor, where efi would be reading it from? And is it reading 1-on the way in or out of engine, and 2 - the high pressurized fuel?
Asking because efi is showing temps around 150 and the sensor I put in is showing 110. Trying to understand why the difference
Asking because efi is showing temps around 150 and the sensor I put in is showing 110. Trying to understand why the difference
Attached is the procedure to replace the factory sensor. I can't tell for sure without looking at my truck, but it looks like it is on the low-side of the CP3.
Doesn't look too hard to get to, you can probably see it without taking anything off.
Doesn't look too hard to get to, you can probably see it without taking anything off.
Fuel temp
I have a 4500 truck in the shop with very high(when it's hot out) fuel temps. I have seen as high as 238 when it was 92 out going up a long hill. When it get's this hot it goes into limp with a 0087. Now I looked for a fuel cooler and the big trucks don't have them. I guess I don't understand why when they have little fuel tanks so it's hard to cool. Has anyone run into any problems with the med duty trucks?? If it stays around 200* it's fine. I still think that's to hot but it works fine there. This is a big service truck and they are screaming they need it. I wonder if I should raise the fuel temp limit a little? I don't want to but nobody seems to have a answer to this. Jeff
I have a 4500 truck in the shop with very high(when it's hot out) fuel temps. I have seen as high as 238 when it was 92 out going up a long hill. When it get's this hot it goes into limp with a 0087. Now I looked for a fuel cooler and the big trucks don't have them. I guess I don't understand why when they have little fuel tanks so it's hard to cool. Has anyone run into any problems with the med duty trucks?? If it stays around 200* it's fine. I still think that's to hot but it works fine there. This is a big service truck and they are screaming they need it. I wonder if I should raise the fuel temp limit a little? I don't want to but nobody seems to have a answer to this. Jeff
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Personally, I wouldn't raise the fuel temp limit. GM put it there for a reason, and 238 degrees is pretty stinking hot. Still well below the autoignition temperature, but it is above the flash point. This means if the diesel were to leak out of the lines at all, it would light on fire VERY easily.
I'd personally look at adding a fuel cooler right after the factory fuel filter. Just run some lines to a cooler at the front of the truck. The only problem with this is jelling in the winter, but you could put a bypass valve in there.
That, and look into an upgraded fuel cooler to replace the factory one. Rumor has it that Mike L. made one in the past.
If you do decide to raise the limit, let us know if anything happens. I suspect not (unless you have leaks), but I'd be curious to hear the results.
I'd personally look at adding a fuel cooler right after the factory fuel filter. Just run some lines to a cooler at the front of the truck. The only problem with this is jelling in the winter, but you could put a bypass valve in there.
That, and look into an upgraded fuel cooler to replace the factory one. Rumor has it that Mike L. made one in the past.
If you do decide to raise the limit, let us know if anything happens. I suspect not (unless you have leaks), but I'd be curious to hear the results.
The factory fuel temp sensor is in the fuel return line close to the glow plug control module.
That's odd...my dad's '03 4500 came with one just like what's on the smaller trucks.
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I've been running the MikeL Double Fan Fuel Cooler for 2.5 years. The fans are on all year round with no problems to date. I even ran them the week we had -30*F temperatures before wind chill with no gelling of the fuel system. I run Kennedy Twin Lift Pumps feeding a Racor 690 filter system on the frame rail. I pulled the factory fuel cooler and placed the MikeL Fuel Cooler up under the bed on the frame. I never set up thermocouples in the before or after lines to see what the temperature differences are. I have seen a solid .5mpg gain from this on current ULSD.
paint94979
I could read the return temperature from the factory sensor.
lotsofmiles
Just to see if it would actually cool the fuel to the point of gelling in the filter. Besides this helps out with people who might wire the fans in on key on power to run all the time. Have you looked at Class 8 Rigs they run a rather large fuel cooler in direct air flow year round. IIRC the last one on my Dad's Kenworth was probably 14" X 16" X 2" thick on a C15 Cat.
I could read the return temperature from the factory sensor.
lotsofmiles
Just to see if it would actually cool the fuel to the point of gelling in the filter. Besides this helps out with people who might wire the fans in on key on power to run all the time. Have you looked at Class 8 Rigs they run a rather large fuel cooler in direct air flow year round. IIRC the last one on my Dad's Kenworth was probably 14" X 16" X 2" thick on a C15 Cat.
I did a bunch of testing "cool fuel" after a wise man told me 75 degrees was optimal. Ours was only power testing, no mileage testing. We had water to air IC & FICM cooling also. Tested all indepently of each other & then combined. IMO, For towing I could see a better cooler on the return where the tank can increasingly get hotter the more you drive. On the pulling track the fuel tank does not get hot enough for long enough to matter. I had it all the results on my laptop that crashed after a fall. Sadly the only things saved are in my memory 
I can share that we no longer have Air to water, any cooled fuel & my FICM is dry
I can share that we no longer have Air to water, any cooled fuel & my FICM is dry 
http://www.dieselplace.com/forum/showthread.php?t=113643&page=4
Looks like a real slick setup. Guess I'd have to mount something that size on the plate over the driveshaft ? Room is at a premium on mine.
Looks like a real slick setup. Guess I'd have to mount something that size on the plate over the driveshaft ? Room is at a premium on mine.