Engine/Transmission (1998.5 - 2002) Cooling the VP44 (fans or fins)?!?

[RJPotts]

When I turn on the A/C and its hot outside and I'm not moving very much my truck starts to run like crap and won't go away until I turn it off for a while.

With the help or fellow TDR members I've decided that the VP is getting too hot.

I heard that some people have made cooling fans and heat sinks of some sort to combat this problem. Any pictures or instructions would be a great help. I work with phone systems and computer systems so I have a VERY B R O A D selection of heat sinks and fans of all sizes that I could rape from scrap cards.



Thanks a lot in advance,

-R. J.

 

[Ron Bissett]

To hot ?

:-{} You decided the injection pump is to hot . I think the injection pump is cooled by the fuel going through it . So I think you should look at the lift pump for the heating of the injector pump it probably is not putting out the extra 75 percent it needs to cool internally . Changed the fuel filter lately ? Do you have a fuel pressure gauge ? if not get one. You may now be running on the injector pump only as the lift pump whet south and you do not know it . Ron Bissett in Metro Louisville KY :-{} I did not see the fact you have a fuel pressure gauge but it could be a stuck return valve or like I stated the filter or the lift pump . Oo.

 

[mlockner]

Big rig trucks actually run a fuel cooler on them, so they run better in hot weather.



Mike L.

 

[ThrottleJockey]

Yeah, like Mike said, I'm thinking about running an auxillary trans oil cooler to the VP-44 from the FASS.

 

[keimmmo]

Cooler fuel going into the injection pump will do WAY more to cool it than a fan blowing hot engine compartment air over it!!! I agree with the first post... first make sure everything is working properly. Have you checked for fault codes?



Steve

 

[McDowra]

A fan blowing air will not do anything to cool the vp44, we have done some research trying to find a viable solution to this problem. A lot of times the ambient air in the engine compartment will be hotter than the vp44. We are close to having a cooler ready to sale that will keep the vp44's electronics at a desired (preset) temp.



here is a picture of the unit (unhooked) on our test truckcooler pic here

 

[BarryG]

Cooler fuel will certainly help cool the pump internals but will it help cool the electronic portion as well. It should to a certain degree I am sure. (by the way not knocking the fuel cooler idea I think it is good). However as far as a fan or heat sink I would think a heat sink would be better than a fan. I would think with all the airflow under the hood that a fan might be fairly ineffective(at least in the size you would be able to use in there) and a heatsink would work better as the airflow under the hood would help dissapate the heat from the sink quicker.



Also I have never seen a vp out of the engine or even one with the cover off so I may be all wet just hinking out loud.

 

[RJPotts]

I figured the fuel would be the best option, but according to my gauge the LP is fine, I changed the fuel filter the same day this happened last.

I guess I could fab something up as a fuel cooler.

I would like a RASP, what do they cost???

Its not a huge deal that I can't turn the A/C on full blast, I usually just have the windows down anyways, but sometimes its nice after its been baking in the parking lot all day.

Thanks everyone,

-R. J.

 

[MKoth]

The fuel cooler would need a bypass for cold weather operation.



The Chevy/GMC Duramax trucks run a cooler on the return line to the tank, maybe that would be a more viable situation, as you wouldn't need to worry about gelling in winter time.

 

[rweis]

I just had my VP replaced under warrantee ($2k, on vacation no less) 53k.



We (dealer mechanic & I) could clear the 0216 and drive normally (~60 mph) O/D on and NOT set the 0216. However when we drove O/D out and ran it hard (3k rpm) it set the code everytime. Dealer said it was a temperature problem with the VP electronics. I tend to believe it because, drive it easy even up to 60 mph no codes. Drive it at the same mph but O/D out (ie higher rpm) set the code right away. Even drove it normally for 1/2 hour no code, but set code when driven for 1 full hour (O/D in ~ 60 mph).



I am VERY interested in keeping my NEW VP cool and well fed. I am starting with the RASP approach. Definitely warrants looking at. Somehow keep the VP cooler and the VP electronics cooler.



Cooler before the VP? or after the VP? or on the RASP bypass? and would cooler fuel cool the VP electronics?



Bob Weis

 

[keimmmo]

Since the electronics set on top of the pump, cooling the pump would HAVE to do some good for the electronics. Correct me if I am wrong.



Steve

 

[RJPotts]

Sounds plausible to me. As for the 0216 code thrown when you get on it as opposed to driving easy, every VP seems to die a different way (symptoms usually the same though) but it does make sense that you're making more heat inside and around the VP at higher rpm. Mine usually only runs like crap if I'm in traffic or something with the A/C on whether I'm driving easy or getting on it. When I'm on the interstate and moving along pretty fast, no problem.

-R. J.

 

[Gary - K7GLD]

"Dealer said it was a temperature problem with the VP electronics. I tend to believe it because, drive it easy even up to 60 mph no codes.



It's long been my contention that the vast majority of VP-44 failures are electronics related, rather than mechanical - and it's also pretty well been established that the VP-44 internal electronic "brain" is sensitive to heat - to the point Bosch in later production, developed an upgraded board to better deal with that heat.



Unless the ELECTRONICS THEMSELVES are somehow provided with better cooling - and I seriously doubt cooler fuel will do that significantly - premature failures are still likely. I doubt there is enough "heat sink" between the VP-44 control board and body of the pump to provide much heat transfer, and even at that, heat soak in high summer temps will still do their damage after the truck is driven, then left to sit - and fuel flow stops.



I'm more interested in directing a steady flow of cooler OUTSIDE air directly across the upper portion of the pump where the electronics live, and also across the APPS for the same reasons. This can be done by use of tube ducting, taking air in from the front grille area - and then enhanced by use of a small fan that will stay on for a preset time after the truck is shut down.



I'd be FAR more interested in THAT aftermarket solution, than cooling the fuel, because I think it more directly affects the problem area. Guess we need a comparaitive test run.

 

[Diesel Freak]

A fan blowing air will not do anything to cool the vp44, we have done some research trying to find a viable solution to this problem. A lot of times the ambient air in the engine compartment will be hotter than the vp44. We are close to having a cooler ready to sale that will keep the vp44's electronics at a desired (preset) temp.



here is a picture of the unit (unhooked) on our test truckcooler pic here

I was thinking of something like that a while back, but abandoned the idea when I realized that with the way the VP is made, the plastic under the pump cover won't allow much heat if any to dissipate into the finned heat sink.



you must be directing outside air across the heat sink to get any cooling effect.



I am going to incorporate a fuel cooler on the return line to the tank downstream of both the head and VP to remove most of the heat in the fuel.

 

[Gary - K7GLD]

"here is a picture of the unit (unhooked) on our test truckcooler pic here"



Sorry to be a sceptic, but for a heatsink like that to cool the electronics inside the VP-44, it absolutely MUST be in total direct contact with the computer board for heat transfer to occur, and probably a liberal amount of heatsink paste to enhance that transfer.



I suspect that all THAT heatsink is doing, is cooling the LID at the top of the Vp-44, and not much else - have you any way to actually MEASURE any cooling directly at the board to prove there IS any cooling effect on the board - and again, what about heat soak when the engine is shut down and fuel/airflow stops?



It's fine to possibly cool the electronics while in motion - but NOT good to toss all that out when the engine gets shut down after a long hard drive!

 

[McDowra]

it's ok you can be a sceptic if you want . The heatsink is not doing the actual cooling it is only moving the heat away from the cooler. This is not a passive cooling setup, and it will replace the entire front cover of the pump, it does require the use of thermal putty not thermal paste on install. We can actually cool the electronics to around 30 degrees F for short burst 30-45 seconds. The goal is to be able to cool it to ~90-120 F (adjustable) and maintain that temp no matter what truck running or stopped. We are a little ways away from that point though.



As far as when the engine stops the board does heatup again that is the problem we are working on now we can cool the pump without the truck running but we are afraid of locking the pump up. So we are working on a more precise temp control unit

 

[tractorface]

Nice. Get that thing done soon. Any ideas on how deep in debt a guy will need to go to have one of them fancy dancy coolers on his rig :-laf

 

[Gary - K7GLD]

it's ok you can be a sceptic if you want . The heatsink is not doing the actual cooling it is only moving the heat away from the cooler. This is not a passive cooling setup, and it will replace the entire front cover of the pump, it does require the use of thermal putty not thermal paste on install. We can actually cool the electronics to around 30 degrees F for short burst 30-45 seconds. The goal is to be able to cool it to ~90-120 F (adjustable) and maintain that temp no matter what truck running or stopped. We are a little ways away from that point though.



As far as when the engine stops the board does heatup again that is the problem we are working on now we can cool the pump without the truck running but we are afraid of locking the pump up. So we are working on a more precise temp control unit

AH - you must be using one of those small solid state refrigerator chip thingies like used to cool portable refrigerators - and that must be the 12 volt power leads seen in your photo - great idea!



Sounds good - keep us posted!



(EDIT)



As an afterthought, wonder if there's enough clearance for a similar device to attach to the APPS - it has many of the same temp issues as does the VP-44 - you might give it some thought...