http://www.eng-tips.com/viewthread.c...=41445&page=35

Here is some good reading, enjoy.

 

Well, dip me in oil and call me slick!

Dealer changed pump and crank sensor and the truck runs GREAT!

No CEL, no problem!

Oddly enough, WOT FP went from 10 down to 9-- could the new VP be pumping more fuel?

Best of all, WARRANTY COVERED IT ALL (minus $100 deductible).

Big thanks to Cowboy Dodge in Cheyenne-- great service. Special thanks to Matt Peters, the service manager and Gary the diesel tech.

Justin

 

It appears to validate my basic reasoning, doesn't it??

 

Classic. Absolutely classic.

Matt

 

Is that a question?

I read in some older TDR posts where the return from the VP44 was 30 gph, tested by a memeber with a flow meter. A missing piece of the puzzel is at what temp. is the fuel when returned to the tank? This would be helpful to know for your application of a fuel cooler. I'm also starting to understand the need for an additional regulator which bypasses fuel back to the tank as it can take some stress off the fuel pump during idle condition when there is not a greater demand for fuel.

I have my fuel pump set at 8psi, but it has a internal regulator which recirculates fuel within the pump, hot fuel. The pumps motor is not cooled or lubricated by fuel, but I think there is some heat transfer to the motor from the fuel even though not much fuel is being bypassed it could help to add a external regulator.

As far as the heat sink on the IP's brain, would that attach to the metal pump wire cover?

 

Yes-- the "pumps lines what not" thread on TDR. Good reading-- everyone should make the time to read it.

Yes, the temp of the returned fuel would have been nice to know.

As far as the heat sink on the IP, it would just go right on the pump cover-- the shiny (at least on my NEW pump it's shiny) top part held on by "tamper proof" TORX screws.

I'm betting I'll have to cut down the heatsink as it will probably be too tall to fit under the APPS/bellcrank housing.

Here's a link to that "pump lines what not" All-star TDR thread, since you can't find it via search if you aren't a member.

http://www.turbodieselregistry.com/f...ad.php?t=11672

Enjoy the reading.

Justin

 

Hohn, I went to a salvage computer parts store and found a plethora of heatsinks, some with or without a mounted fan. Do you think a fan would be needed in our apps? I don't know if it would do much good other than after shutdown. If a thermal on/off switch could be part of the circuit that would be more useful. Any ideas? I'm not too sure but I think building a simple circuit board wouldn't be all that difficult.

Do we have any Electronic engineers or computer experts?

 

I think a fan is unnecessarily complex. A simple sink should give you 90% of the benefit at MUCH less headache.

 

Thanks for the input. I'll go shopping at lunch.

 

Question regarding the conductive paste. Is this used as a adhesive or just to make better contact? I picked up a couple of heatsinks, but they didn't sell a conductive adhesive. I really don't want to drill the cover to mounts these heatsinks.

Also, is that paste just dielectric grease?

 

Yes, it's both a conductor and an adhesive. It has real silver in it, which is the best conductor (of both heat and electricity).

They sell the paste at Circuit City, and it's not cheap. Like $13 for a tube. You're paying for that silver, eh?

I ended up getting a heatsink for free from a local computer house that was gonna throw a bunch away (it's an obsolete design). I may end up skipping the freebie and buying a fancy one with the fan. Most of those little fans are 12VDC, so it should be easy to to wire up.

jlh

 

Since many of us are having the VP44 issue I think it would be a good idea to document our issues with the NTHSA. We can let them know we have an issue and that this issue isn't isolated to a few trucks.

http://www-odi.nhtsa.dot.gov/ivoq/

Let's see if we can get some attention to a serious issue.

-CM

 

After you get home from driving your truck for a while and the motor & everything under the hood is too hot to touch, put your hand on your injector pump and notice the temperature.

 

It's amazing how it's so much cooler. Even the bracket seems hot by comparison.

I'm re-thinking my heatsink idea, as it probably won't contribute anything, since the VP cover doesn't get much heat.

jlh

 

I installed two heatsinks last night. One on the IP cover and one on the bottom part of my electric fuel pump. I had my doubts as to how much the heatsink would help.

The difference felt by touch is truely noticable. I only wish I had a inferred temp gun to measure before and after results.

Reporting results without a good measuring device is less than ideal.

I spent less than $10 on this little project.

Maybe someone with a good way to measure temp. changes will try it.