Engine/Transmission (1998.5 - 2002) Modifying fuel system so temperature input to VP44, 80* - 100*, your inputs.

[Mundgyver]

It would be interesting to conduct a poll to see what the average life of the VP-44 is. I am still running my original with over 150,000 miles on it and no sign of it going bad. With that said though, I have installed a FASS about 130,000 miles ago and at the same time increased my fuel inlet from a restricted banjo fitting to a wide open 3/8 ID line. I know that this change was for the better in looking for a reliability factor on the VP.



Now with the addition of a fuel cooler, I think that my reliability factor just went up another couple of notches. I aggree that in a real cold climate, one could over cool the fuel to the point of having it start to gel, but with that said, what choice do I have for when I am in 110 degrees and towing 9,000 lbs. Come winter, I can always cover the cooler up and run that way. If I can keep the VP cool in the summer and not have to worry about killing it, then I have saved myself the price of a VP (large money) for the price of the cooler (small money).



Eventually as time permits I will add a couple of temp probes to the cooler, one on the inlet and one on the outlet, which will allow me to monitor the efficency and just give me one more small tool for trouble shooting problems by being able to observe changing symptoms.



For mileage increas, I can't say that this will work, but there is a hint that it could. This Friday will will be able to confirm that suspicion with no problems.



In the end, for me it is all about reliability. After 150,000 + turns, I still have my original clutch, original factory brakes, and original VP. I run full synethic oil throughout my truck and have a Spinner II to actively remove the soot from the engine.



Reliabilty is the bottom line for me. The longer it last, the cheaper it is to own and operate, although the gas companies are rapidly doing away with the cheaper to operate idea DIRTY BUGGERS #@$%!



Almost forgot, I get a rock solid 23/24 mpg on trips, provide I am reasonable and prudent in my driving habits. If the cooler can increase this by . 5 mpg besides increasing the longetivity of the VP, then it is just a little more benifit to the economics of ownership and maintenance the long run.

 

[CORed]

So just what is the temperature at which normal #2 diesel begins to turn to gel? Anyone know?

 

[rweis]

With or without fuel conditioner (Stanadyne PF for lubrication, pour point, etc).



Stanadyne web page (http://www.stanadyne.com/new/ppt/showfile.asp?id=1295) says it lowers pour point by 60* F.



Bob Weis

 

[rweis]

I think what this is "boiling down" to be is to use different tools to keep the VP input fuel cool. Which tools where and when?



Earlier I posted that the afternoon (97*) drive home the Vp was more than warm to the touch. I was a little surprised the return fuel was so warm. Of course the tank fuel was 97*+ also. (When the fan is hooked up in a day or so) Turn on the fan on the fuel cooler if it is over 80* outside to help dissipate the VP heat generated. If cooler than 50* then I do not need the fan to be on. If I am towing the 5er probably turn on the fan on the fuel cooler as insurance.



I will have a fuel temp gauge on the input to the VP to help me see what is happening with the VP "cooling" system.



On commenting about the fuel cooler after or before the VP.



Before helps the VP more, after helps the tank more. However, if it is 100* OAT you start with 100* input "cooling" tank fuel to the VP if you have the cooler on the return line. You have to cool the entire fuel mass down to get the input temps lower. However, you have the largest temp differential on the return line.



On the VP input line you have a MUCH smaller mass of fuel to cool. I would think it would be much easier to cool the input line. Then of course the tank fuel gets hotter and hotter.



Both places? Maybe too much!



I am going to see what the input fuel temperatures are.



Just some thoughts,



Bob Weis

 

[Mundgyver]

I don't think the tank fuel will get hotter. The reason is that the return line dumps into the tank at the pickup point, at which time the fuel is routed back to the VP along with additional fuel from the tank. If the return line dumps at a different location in the tank, then I would aggree.



This reasoning is why I decided to put the cooler in the supply side to the VP. It then does not matter about the tank temp.

 

[CORed]

Thanks Bob.



From the link you sent me, it says normal fuel gels at -6* Fahrenheit, but with Stanadyne, it gels at -60* F. I don't think gelling will be a problem, even in cold weather under most circumstances. And like Mundgyver said, the rest of the fuel in the system will be warmer, we would only be cooling the fuel between the cooler and the VP44 in your scenario and that is a very short distance of which most of it, after the cooler, is in the engine compartment.



Thanks again.



Steve

 

[SKneeland]

i didnt mean to make my last post sound like i was knocking mudgyvers setup, i actually will probably end up using the same parts, but installed on the return lines. was just looking for more input from other readers on whether return line or supply line was better. i agree supply line should have the most "felt" impact on the VP, but i prefer to keep things simple. i have heard theories that cold/semi-gelled fuel will start to "wash" the injectors after prolonged use.



also bought a 2$ heat sink from princess auto that im gonna glue to the VP, lol

 

[Mundgyver]

I do not see any knock at me. I think we have a good discussion going in a search for ideas to find the best applicatons for our needs. Everything that has been put forth is good viable insightfull reasoning. Location by climate plays a big factor. What works for one area might not work for another.

 

[Gary - K7GLD]

I do not see any knock at me. I think we have a good discussion going in a search for ideas to find the best applicatons for our needs. Everything that has been put forth is good viable insightfull reasoning. Location by climate plays a big factor. What works for one area might not work for another.

Actually, I prefer your setup for it's simplicity and ease of blocking off the cooler when it's cold out. Don't think I'll need to go that extreme to get VP temps close to 100 Degrees - and my shadetree ducting for cooling air will probably get me there, as well as providing cooling airflow after the engine shuts down to control heatsoak - the fan is now mounted, and waiting for the time delay relay to arrive - it's due friday, but dunno if I can get it wired prior to our RV trip - may temporarily just wire the fan to an off/on switch...

 

[rweis]

GREAT reading!



Enough different guys trying enough different approaches that something should come out of the results.



And THIS is what TDR is all about.



Loving every minute of it!



Bob Weis

 

[RClark]

Mundgyver, I just realized why your setup won't work for me. My Auto transmission has a cooler there so no room.

 

[rweis]

I put my (ETC) cooler and fan back under the bed on the driver's side, but I did a return line cooler and dump it into the tank vent line.



[I also have my RACOR 690 fuel filter and my RACOR LFS 802 bypass oil filter back there (and yes I have run out of room for "stuff" :{ ]



Bob Weis

 

[Mundgyver]

Yep I do have a manual transmission so I did have some room. I had considered mounting it under front and building a NASA scoop for it using my CNC plasma cutter. But I opted for infront of the radiator instead.

 

[rweis]

Your CNC plasma cutter, beats my hacksaw anyday Oo. but I get areobic points using my hacksaw. Oo.



Bob Weis

 

[Mundgyver]

I use to be arobic when I was in service and in my prime. Now the wife just thinks I have aroma and noise problem, Diesel and Exhaust I think

 

[AJ]

SKneeland, depends of what you want to cool, the tank or the VP...



I put mine in between the pumps(17 months ago) and factory filter housing utilizing the oem "thermostat" and heater for that very reason. I have been in the freezing cold a couple of times with no problem.

I also drilled out the filter to 1/4npt to utilize the 1/2" hose. . Soon the fass is going in

and the factory filter stays. 5 carters since jan 03 is getting old.

Last note, since you live up north you might not need the largest cooler available, you already have the flow!



AJ

 

[SKneeland]

cooling the tank will cool the VP. with the cold climate up here i want a system i can install and forget about (not worry about covering the cooler if its too cold out , etc. ) A cooler on the supply line to the VP with a thermostatic bypass would be the best imho, but then once again you end up having pieces that can be prone to failure

 

[keimmmo]

I have been following this thread with great interest. Making the VP live longer is always a concern. With the cost of fuel, even slight improvements in fuel milage are also interesting. I will rarely see freezing temps, so gelling is not a personal concern.



It seems to me that a cooler ANY place in the system will help deliver cooler fuel to the VP. Cooler fuel entering the VP should mean cooler fuel coming out while still keeping the VP cooler than factory stock.



While there is certainly plenty of room under the truck to mount a cooler, the air under the truck will be hotter than the air in front of the truck. Even with an extra fan to move air through the cooler, you will get better results in front of the radiator than under the truck. I do not like the idea of an extra fan either since it is one more thing that can fail.



I don't see that it really matters what the temp of the fuel is in the tank. What matters is the temp going into the VP.



For the reasons I have mentioned, I would rather put the cooler in front of the radiator and cool the fuel as it enters the VP. Also, there is already a rubber hose connecting the lines between the fuel filter and the VP. It would be easy to install the cooler lines at that point.



A small trans cooler would be ideal. But, WHERE am I going to find one here in Mexico... and even if I do, where will I mount it? I remember years ago seeing a Ford (the better idea people?) with a loop of hard line in front of the radiator to cool the power steering fluid. What are your comments on putting copper tubing in front of the radiator? Six feet would be easy. I could do twice that without much trouble. It will fit between the radiator and grill without a problem. Again, a real cooler would be more efficient. But, wouldn't the tubing help?



Thanks to all who are working on the project. I await your comments.



Steve

 

[Mundgyver]

A single line of copper pipe will drop the temp some, but the Rapid Cooler will divide the flow of the fuel into individual channels. The copper pipe will flow fuel at what ever the rate the pump is putting it out. Also the additional length of run will act like a restrictor. This is a length / diameter / pressure thing. The Rapid Cooler divides up the flow into parallel paths. Because of this parallel concept, the fuel passing through the core actually slows down and is exposed to cooling longer. Comming out of the core at a single point it is re-combined and returnes to normal flow rates. The engineers have a term for this in their fluid dynamics class. Thats why radiators are so effective.



If you use the pipe, and you have a fuel pressure gage, it would be very interesting to see what the pressure is before and after the install. My bet is that you will see a drop in pressure with the additional length of line. To over come this you would need to increase the diameter of the line for less restriction.

 

[keimmmo]

I work with gravity feed water systems all the time and understand what you say about a long pipe being a restriction. I didn't say it in the last post, but I planned to use slightly larger diameter tubing.



Also, I DO have a fuel pressure gauge at the schrader(sp?) valve going into the VP. If my "invention" drops the pressure, I will know it.



Steve