Well, since so many of us are experiencing the illustrious springtime/summertime VP failures, and we are beginning to associate a lot of these failures, (ie. dead pedal syndrome), are due to heat related issues with the electronics portion of these pumps, I have just come up with what may be a brilliant possible solution to fix this overheating issue.

What if one were to provide a small "ram-air" style cooling duct from the front of the truck and tie into the cover of the VP-44 Assembly. This would provide the pump with ambient temperature cooling instead of the 175-250 degree under hood temps that it constantly sees (except in winter).

My idea is to build a box with a concentric reducer down to a 3" hose/duct assembly which would tie into the VP-44 cover. Mount the box in the front air dam on the drivers side and duct up to the VP cover.

If water infiltration becomes a worry, we could duct over to where the stock airbox used to get its air (for those with a Scotty or Bhaf) and install a 3" pancake fan to push air over to the VP cover.

What does anyone think about this??????


Gary

 

Sounds like it may work, I believe some may be trying the same approach already. I opted to try the heatsink route.

 

Sorry don't think that it is too practical for the amount of cold air needed to be effective would be huge. Perhaps a three fold increase in fuel flow might cool the internals of the pump better. For its the internals that are needed to be cooled.

 

Never, I am talking about cooling the electronics portion of the pump. I think that the mechanical cooling issues have been resolved in the revised VP-44 designs. The older VP's had internal tolerance problems on moving parts. The upgraded design to which they are currently rebuilt seems to have satisfied that issue. It is the electronic portion of them that is currently resulting in many of the dead pedal issues a lot of us face lately. I know that the issue with my VP is electronic because I have learned that when it suffers the dead pedal, I can turn ignition key off/on while driving and the dead pedal problem goes away for a while. It has been doing this for the last 55K miles. It is my reasoning that when the key is switched off/on, it resets or spikes the electronics to the VP and causes it to operate properly, albeit for only a while sometimes.......

Gary

 

I agree: the internal mechanical components needs cooling. But that's a fuel circulation problem, and it's been largely solved by later VP44 upgrades and fuel delivery upgrades. Internal mechanical heat may not be the problem affecting pump electronics and thermal cycles. On my IP, I've got a thermal barrier between the electronics package and the mechanical pump - a thin sandwich of fiber and plastic. Checking it with a temperature probe after a highway run in 90*F weather, it seems to do the job. Apparently the real problem is the ambient temperature at the top of the engine under the hood. At idle and slow speeds, the temperature registered 120-125*F. At cruise, it was 135*F. After cruising at 65mph and then slowing down, the temperature spiked at 163*F for about two minutes, and then slowly fell to 130*F.

That's fairly hot. It's apparent that the electronics package needs a thermal solution. Sticking a heavy-duty heatsink and 12v fan (like a CPU or GPU heat dissipation device) on the top plate of the package -and- funneling cool air across the fan and heat sink might do it.

 

Heres a good link to tdr about adding a fuel cooler for the vp-44 electronics.

http://www.turbodieselregister.com/f...d.php?t=135952

 

That's City Diesel of Decatur, Alabama, that's developing the active cooling system for the VP44 electronics package. They've created some good products, and I'd seriously consider buying that solution when it's ready.

 

Airplanes use "ram air" designs to cool critical electronics like alternators, magnetos, voltage regulators. You might be on to something.

My fix is to keep the engine & radiator CLEAN. I power wash the engine 3-4 times a year and hose out bugs every car wash. Also, keeping the tank full keeps the fuel cooler than 1/4 tank, and less air.

 

not to jack your thread but.......i get the idea but what someone please explain what VP44 is.......sorry to be such a noob

 

VP 44 is your injector pump model all 98.5- 02 have vp44s

 

Thats a real interesting mod using a refridgerant type heat sink on top of the vp. A timer could be added to keep the electronics cool after shutdown so they will not have any heat saturation from the motor..

 

Ok fellas, I have been thinking about the same thing, something to move cooler air over the IJ, My dad has a 88 toyota landcruiser, and it has an aux blower motor that blows over the engine and it moves alot of air. I have been thinking about fixing it up on a timer that will run while the engine runs and stays on bout 3-5 mins after you turn the engine off. What do you think about that idea?

 

So I'm assuming the VP electronics is under the plastic cover on the pump. I haven't taken anything apart just to take a look yet.
Just from looking things over today, I would guess that some wizzardry with some ABS plastic and you could make some kind of duct to direct air from in front of the Rad and A/C to the plastic cover. a large flex tube going down towards the ground with a back slash might make the whole thing flow a significat amout of air over the electronics. If it was just 30 deg F cooler than underhood heat it would sure help I would guess.

It would seem that some reduction in input fuel temp happens when the LP is frame mounted.

Maybe Scotty can come up with an air duct.

bentwings