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i had an idea of doing something like this and have a separate battery hooked to a dashboard solar charger constantly hooked up. they dont draw much power and i think would work.but then you need to ensure there is some kind of medium making contact from the board to the heatsink face

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BlueChip Diesel mentions trying this approach without success. http://www.bluechipdiesel.com/about_lift_pumps.html That doesn't mean it's not worth trying... just that BCD has not been 100% successful yet. The VP44 is a hunk of metal, mechanically physically connected to a HOT hunk of metal. It's going to be hard to keep it from heat soak. Maybe a cool down timer makes more sense than ever. Boats are required to have bilge ventilation to prevent buildup of gas fumes... usually connected to clamshells by 4" flex hose. I had an assembly contract with a small local builder... still have my 4.25" hole saw from installing the vents.

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It really hard to cool VP44 electronics when the electronics are wrap in plastic on 3 side and the bottom side facing the fuel is aluminium. Like I found as long as you keep the fuel pressure between 14-20 PSI the electronics stay happy while running. Now as for when you park you truck. It meaningless kind of. Like taking a laptop computer and tossing in in the back seat on a hot summers day and locking up the truck. The cab of the truck will get to 130-140*F easy. The laptop will feel no harm as long as if left off. Now if you fire up the truck the fuel will start flowing instantly cooling the electronics so there is very little time the electronics would operate in a heated environment. But if the fuel system wasn't able to get above 14 PSI it like turning on that laptop inside the truck at 130-140*F that will kill a VP44 or Laptop.Everyone assumes Idaho has mild summer and super cold winters... Just yesterday we made 90*F here at the house and it most likely 100*F in Riggins, ID. Nothing new here. I've seen days of 120*F in Riggins, ID... :wow:My VP44 is closing into 150K miles and still going strong... :thumbup2:

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It will display the fuel temp where the sensor is just below the computer in the fuel. The little ribbon cable. post-2-138698189225_thumb.jpgNotice the bottom is aluminum...Now the top is plastic...post-2-138698189228_thumb.jpgNow notice the electronics are mounted to the aluminium not the plastic so no matter what blower or heat sink you make it not going to cool the electronics. But keeping good fuel flow under the pump 14-20 PSI that problem is no longer a issue.post-2-138698189237_thumb.jpg

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This might sound crazy, But why don't we just leave the LP on for 15 minutes after shutdown? (or longer or shorter, or in 1 second bursts every 5 seconds for 30 minutes etc...) It seems like you could use the "cooler" fuel in the tank to at least mitigate some of the heat soak to the electronics. (you obviously wouldn't want to turn on the fuel heater or anything.) I don't see why this wouldn't work. I had thought I would test it, before I proposed it, but I cannot find an "easy" way to trigger the LP since the ECM does the relay internally. So doing it externally it would be a parallel relay and diodes etc etc.Any thoughts?Hag

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but another lift pump...and install "T's" before and after lift pump that is running the truck..install a toggle switch that is powered just by the battery because the one driven by the ecm will be off..and walla??maybe?

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This might sound crazy, But why don't we just leave the LP on for 15 minutes after shutdown? (or longer or shorter, or in 1 second bursts every 5 seconds for 30 minutes etc...) It seems like you could use the "cooler" fuel in the tank to at least mitigate some of the heat soak to the electronics. (you obviously wouldn't want to turn on the fuel heater or anything.) I don't see why this wouldn't work. I had thought I would test it, before I proposed it, but I cannot find an "easy" way to trigger the LP since the ECM does the relay internally. So doing it externally it would be a parallel relay and diodes etc etc. Any thoughts? Hag

Won't work because once the engine stops twisting the flow stops in the injection pump as proven here is this video... BC was going to build a lift pump timer to keep it running but I figure it out that it won't work because there is next to zero flow...

http-~~-//www.youtube.com/watch?v=YREpPrMxkHU

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I want to write a book here....But it boils down to, we could remove the "system relief" banjo screw. Use a light check valve to prevent back flow (though the original design with the small hole bypassing the relief function does not operate as a reverse check valve). The VP44 was designed around the Carter LP which does not use on lift pump downstream pressure regulation. So according to good hydraulic design, there has to be a system relief. (otherwise in many cases the pump will just sit "dead heading" which is Hades on a pump due to the uncontrolled internal recirculation, and then the designer worried that the relief might not work and put a small "leak" around it...) Most of us that would like this do have pressure regulation at the pump, and do NOT need two (2) items in the system trying to regulate pressure. (I think this is why at the end of the video you only get the flow through the small hole..... something else in the system is letting your flow "go back to tank" (the adjustable regulator on your pump)) The reason I say this, why would your killer LPs slip down the flow head curve? You don't get a corresponding pressure spike to the sudden reduction in flow. The two relief systems play games with each other. They will not be consistent games either. There is also the problem with non-absolute regulators....you can get a masters thesis out of regulators, but non-absolutes can and do easily slide their regulation window based on upstream pressure.... (both of "our" regulators are non-absolute...)I hope to test this. I can't right now, too many projects require the truck to run... but i really want to. I have a donor stock lift pump, I am looking for a dead VP44 if anyone has one. Need to cut some of the internals apart to see.The bottom line though is lets say what we saw is the real truth. (I have provided no evidence that what we saw is not true. This "shouldn't happen", but cannot at the moment provide a real reason other than a hunch.) The small flow of fluid from the VP44 would still carry heat away with it, (and due to the low flow, would have a much higher specific heat efficiency than full flow) If some one can tell me either the flow of fluid through the hole, or the diameter of the hole, I can calculate the energy that could be removed. (I need a dead VP44 to calculate the theoretical load.... I have to figure mass and surface area.)I have a bottle of asprin or Ibuprofen (or single malt, my favorite) if you read through this. Drop by the house and we can discuss it and draw pictures on the deck with the boys chalk. Hag

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I want to write a book here.... But it boils down to, we could remove the "system relief" banjo screw.

Not really... Because you want to keep fuel pressure at 14 PSI for the VP44. Thats why the last check valve just like the P7100 pump and VE pump are the same way...

Use a light check valve to prevent back flow (though the original design with the small hole bypassing the relief function does not operate as a reverse check valve). The VP44 was designed around the Carter LP which does not use on lift pump downstream pressure regulation.

Actually the carter has a internal regulator too that routes extra fuel from the output back to the input flowing across the motor as lube and cooling.

So according to good hydraulic design, there has to be a system relief. (otherwise in many cases the pump will just sit "dead heading" which is Hades on a pump due to the uncontrolled internal recirculation, and then the designer worried that the relief might not work and put a small "leak" around it...)

But all pumps have a regulator of some sort. AirDog and FASS with a 3rd line back to the tank, Raptor, FASS95 and Carter with internal return to input, etc.

Most of us that would like this do have pressure regulation at the pump, and do NOT need two (2) items in the system trying to regulate pressure. (I think this is why at the end of the video you only get the flow through the small hole.....

Because the small hole purpose is to bleed air but hold fuel pressure. That's why its so tiny of a hole.

something else in the system is letting your flow "go back to tank" (the adjustable regulator on your pump)) The reason I say this, why would your killer LPs slip down the flow head curve? You don't get a corresponding pressure spike to the sudden reduction in flow. The two relief systems play games with each other.

Not typically no. The problem is that most people don't plan the fuel supply system properly with the demand that they are putting on it. Hence the problem with up and down pressure.

They will not be consistent games either. There is also the problem with non-absolute regulators....you can get a masters thesis out of regulators, but non-absolutes can and do easily slide their regulation window based on upstream pressure.... (both of "our" regulators are non-absolute...)

Actually the regulator problem is trying to build a cheap regulator that works for a long period of time. The carter lift pump regulators fail because the chrome plated BB (check ball) is beating against pop metal body (cast aluminium). S in a short time the BB tears up the seat and pressure drops. On AirDogs the check ball is plastic with rubber coating and it will squeeze back into the coil of the spring which is correctable by egg shaping the last coil.

I hope to test this. I can't right now, too many projects require the truck to run... but i really want to. I have a donor stock lift pump, I am looking for a dead VP44 if anyone has one. Need to cut some of the internals apart to see.

There is a bunch of VP44 pictures over on DTR.com internals, externals, exploded views, etc.

The bottom line though is lets say what we saw is the real truth. (I have provided no evidence that what we saw is not true. This "shouldn't happen", but cannot at the moment provide a real reason other than a hunch.) The small flow of fluid from the VP44 would still carry heat away with it, (and due to the low flow, would have a much higher specific heat efficiency than full flow) If some one can tell me either the flow of fluid through the hole, or the diameter of the hole, I can calculate the energy that could be removed. (I need a dead VP44 to calculate the theoretical load.... I have to figure mass and surface area.)

The best I can give is a single strand of 14 AWG wire will not fit the hole. May take a thou or two off and it would.

I have a bottle of asprin or Ibuprofen (or single malt, my favorite) if you read through this. Drop by the house and we can discuss it and draw pictures on the deck with the boys chalk. Hag

Cool... I'd love to sit down and talk shop with chalk and beer... :wink:
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Well I did some googleing and found a few guys who run the blower idea... I think Im going to try this as a test. Just get a 12 volt boat blower that will run when the key is on and 10 Min after shutdown. Pull air from the front bumper area and push it to right on top of the vp44. Well see what happens. If any thing Ill get a blower to put in the roof of the house to try and push out some of this hot Texas air.

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I ducted a blower to the top of my VP. I only turn the blower on when running a bit hotter from hauling a load or long steep grades, hot summer days, those sort of conditions.But, I do like the duct being able to push cool air from the front up to the top of the VP without the blower turned on. It helps a little, I suppose, but mostly for a worrisome guy like me :duh::).I have to say too if you think about doing this.... It's a good to use some heavy gauge aluminum duct instead of the regular flexible stuff cause it corrodes and starts cracking. It's a little too thin for an outdoor application.

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I can tell you the under hood temperature its between with the outside air temp (105*) is and the coolant temperature (190-195*) As for the VP44 as long as you pressure is 14-20 PSI then the VP44 temp will be the temp of the fuel more fuel in the tank the longer the pump stays cool.We made it 92*F here at the house.

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96 yesterday... 94 today I think. 2 attic fans were supposed to be more than adequate... all 3 are trying to lift the roof off. Need AC in the living spaces like bedroom. I can retreat to the half burried lower level. I wonder if removing some of the rubber seal cowel to hood would increase the exhaust air flow... though it doesn't make full contact.

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There's the guy I was talking about. Do you have any pictures of this set up? Its starting to get 105 here in texas no telling how hot it is under the hood.

- - - Updated - - -

also how did you do the heat sink on top?

Mopar Mike can you place a link in this thread for my pics of the VP cooler set up? I worked a hard day and struggle doing something like that right now.

Otherwise I can give new pics on Saturday after a rest.

Thanks Mike.

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There is some good "accurate" information going on here. I like it..... It seems the knowledge of the forums are working. :)If I may, can I throw my two cents in this topic.....The problem is this and this ONLY. The VP computer has lead free solder.....thats it. Lead free solder cant take extreme heat otherwise it deteriorates. Over time that deteriorating solder eventually leads to intermittent and/or no electrical connections. We could try to come up with all kinds of coolers but as Moparman mentioned, as long as fuel is passing through the VP somewhere between 14-20 psi at ALL times, the VP temp will stay plenty cool enough, running roughly between 110*-150*. Fuel temps over 160* are bad and will cause the fuel temp sender to de-tune the engine. The problem lies with shutting the engine off. Shutting the engine off stops fuel flow and causes the engine to heat soak the VP to approximately the same temp as the 190*-200* engine. This is when the solder deteriorates. So if the engine was continually running then the lead free would never be an issue. And if anyone doesnt know this, fuel passes "though" the VP and not just in the inlet and out the outlet. Which is why the engine must be running, turning the VP, for fuel to fully pass through the fuel lines.The best fix I can think if is to simply REMOVE the computer from the top of the VP and mount it somewhere less susceptible to direct heat contact from the hot engine. Sounds simple enough..... But no ones been able to successfully pull this off. Something to do with the surrounding electrical interference the farther the computer gets from the VP causing problems.

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