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

[Texas Diesel]

Once again I learn the value of listening...



Bob, after thinking about your observations of heat gain through the FF, I decided to experiment.



Yes, the FF was as hot as the cylinder head. So I bought two longer bolts and 4 thick (1/8") nylon washers. Two insulate the FF from the head (actually intake manifold) and two insulate the shoulder bolts. After a trip into town the FF was HOT. So I installed the new parts and finished my errands in town then drove home (90F). Upon arrival home the FF was cool (!!!!) and the return fuel cooler (hot side) was noticeably cooler (than other identical runs without the nylon washers) as well. Seems some of the heat in the fuel is being picked up inside the FF like you said.



The difference was dramatic.



Hats off to you!!



Keep on posting!!



If anyone else wants to try this I can put together a package of the bolts and washers in case they arent available in your area.

 

[rweis]

Texas Diesel, GOOD, confirmation is important. Others have a different system than I do and if it works for as many different people as we can get, all the better.



I drive 17 miles to work. In the morning the ff (zip tied to the master cylinder, I did not have bailing wire :{ ) the heat VP ift rises 10* (75*->85*). However, if I drive like 80 miles, the VP ift slowly keeps rising to ~115* (still not HOT) but a lot more than 85*. This is driving empty. In the afternoon drive home much the same. It just starts at a higher OAT. About the same temp rise etc etc etc.





What happens when we are towing heavy ALL DAY through the mountains with OAT 100*, which is where the heat problem really occurs I think.



Where I am trying to go is to get the VP ift the same as the OAT after hours of heavy pulling. I do not think if I care if I can get the tank temp below OAT (probably could not anyway), but that I can get the heat put into the fuel by the VP out of the fuel before it gets back to the VP again.



IF we can keep the ift (input fuel temp) down at OAT then we should never have ift greater than about 110* in Arizona in the middle fo the summer. Which is way lower than the maximum ift of 160*. A 50* margin to the upper limit would be enough I would think to keep the electronics bay at a temp within it's design limit when the heat soak occurs and it is 135*-140* under the hood as Lsfarm measured. The heat soak of the VP will be going up as the heat soak engine compartment temperatures start to fall. Hopefully the VP will not go into high temperature ranges before the engine compartment temperatures get to a reasonable level.



Then when you shutdown for a fuel stop the heat soak will heat a 110* VP rather than a 150* VP and you are 40* ahead of the game before you start trying to control the heat soak of the VP. That's where Gary's air blower duct comes in. I think he has it to turn on the timer when the timer circuit senses the engine turned off.



We are getting close to getting this done I think, been a great ride though Oo.



Bob Weis

 

[CORed]

I'm decided to try Texas Diesel's solution too, except I used nylon re-inforced rubber washers which were just over 1/8" in thickness. I reused the OEM bolts. I only used two washers... one on each bolt. I did not put anything between the bolt shoulder and the top of the FF bracket (for now). I put the rubber washers under the FF bracket directly on the manifold. Took 4 minutes.



I am about to take a 5-hour trip w/ the family to Wyoming today and will fuel up in Cheyenne. Temps are mid-70s to 80s. I will report back in the next few days how the FF housing and bracket felt to the touch when I fuel up. I do not have any infrared gauges or anything that high-tech.



Thanks Texas Diesel for the simple to implement idea.



Steve

 

[keimmmo]

Drove the truck about 2 hours today in temps of only about 75*. Here are my observations:



FF housing just warm to the touch... probably about the 115* Bob observed on his truck.

Inlet side of fuel cooler in front of radiator, about the same as FF.

Outlet of fuel cooler, about ambient temp.

New fuel return line slightly warm... and was cooler toward the back than at the inlet. It is cooling the fuel slightly.

Fuel pre-filter just ahead of fuel tank, about ambient temp.



Now, the pre-filter USED to get pretty warm! So warm that I would have to let it cool to change it! I have no doubt that my fuel temps are considerably cooler than before I started modifying!!!



I will get a REALLY GOOD test in a few days! Sunday, Sept 25, I will be leaving down here pulling the travel trailer up to Illinois. I will be gone about 6 weeks. I should see fairly warm temps while towing, as well as some chilly temps up in Illinois before I head back. If I get a chance to use a friends computer while up in Illinois, I will give you my observations. I will DEFINITELY report when I get back.



I plan to stop for a short visit with Texas Diesel on the way back. We can see each other's modifications and compare notes. Should be interesting.



I look forward to reading any new information you all have when I get back as well. Thanks to all involved.



Steve Keim

 

[CORed]

Well, after returning from my trip to WY after adding the reinforced rubber washers between the FF bracket and the manifold, it definitely seems that the FF and the entire bracket assembly are cooler. I drove 5 hours stopping around 2. 5 to refuel (cheap WY fuel only $2. 62 at the Flying J in Cheyenne). Anyway, I popped the hood and I could hold my hand anywhere on the FF or the bracket for as long as I wanted. Temps were in the upper 70s outside.



So I believe it helped. No real data, but I'm going to leave it this way permanently. Also, it did not come loose at all using the OEM bolts. I'll keep an eye on it, but I think it is one of the cheapest BOMBs (if you can call it that) that I have ever done.



Steve

 

[rweis]

Did an RV tow this weekend, only about 60 miles, relatively flat florida.



What I see so far is:



10* - 15* + OAT when running empty.



20* - 30* when towing in flat land (this tow was 90* OAT and fuel input temp was 120* at the highest and stable readings).



This was not a all day hard pull, but the input fuel temp seemed to be stable at OAT + 30*.



Mechanical conditions:

OEM ff is hanging on the brake cylinder to get it off the intake manifold. VP fuel return is in the tank vent line. Return line H7B fuel cooler w/1000 cfm fan running.



I have had several empty drives over 2 weeks and the OAT + 10* - 15* empty seems to be the case with my setup.



This was the only RV tow, and it was not a long one nor was it under hardest road conditions (relatively flat OAT 85* 60 miles cruise speed 60 mph O/D out)



Will post more as data is gathered.



Bob Weis

 

[Mundgyver]

Just out of curosity, how was your MPG?? Any noticable differance that your could see?

 

[dknoch]

Do you guys think this would be good. Seems simple enough and fairly inexpensive. could get 2 of them, 1 for supply line and 1 for return line.



hope this works



[http://store.summitracing.com/defau...ults=false&N=0&target=egnsearch.asp&x=43&y=13

 

[Mundgyver]

That allot of coin for an aluminum pipe with some fins on it. I used the largest automatic tranmission cooler I could find and my vp does not get hot at all. I installed it in the input line to the VP. I did not worry about the return line to the tank as I figure in the winter I would want warm fuel getting back to the tank anyway to help prevent gel up when I go up in the snow country.

 

[rweis]

On the fuel cooler tube style. I definitely would NOT mount it anywhere it will pick up engine compartment heat. I think the problem with the OEM ff is it is aluminum and easily picks up engine compartment heat. A good thing in the winter, a not good thing in the spring, summer, fall.



The last fittings from Summit for the inline ff will not be here until 10/10. Then I will get readings without the OEM ff.



I do not see anything appreciable in fuel mileage difference so far. I really do not have enough mileage on the diferent mountings to give any real picture. I do keep a spreadsheet of fuel used since I purchased the truck so any change in fuel mileage will become readily apparent. Driving habits probably more of a factor.



Bob Weis

 

[dknoch]

I was thinking it seems like a fairly solid piece that I could mount on the frame rail infront of my FASS system. It would have plenty of cool air around it. I don't really want to change my fuel system seasonally though, do you think it would be OK in the winter here in Ohio. The lake prevents us from getting too cold, rarely any colder than 0 F (cold but not like Minnessota and those guys). I ran the FASS through the original fuel filter housing so I would still have the fuel heater. Maybe insulate the stock fuel filter housing and put 1 on the supply line, definately couldn't hurt but would that be enough to make a bit of a difference? Thanks!!!



Dan

 

[RowJ]

Need more guys with infared temp guns gathering data.

FWIW... . Related to another thread... . I used an infared heatgun to measure fuel temps at the bottom (outside) of the tank.



Gross wt. , full fuel, 85* OAT, 75-80 mph. Ran for 400 miles non stop... . fairly level interstate.



After 400 miles, non stop (1/3 tank left)... . Reading were from 98* to 102*... . three different points on the tank. This is with FASS and no fuel filter canister.



Have not been around this site much over last year... so I don't know if this kind of data has been shown... or if it really helps with the above VP44 subject?

RJ

 

[rweis]

Every little bit helps. Long runs are especially good.



Bob Weis

 

[jjohn]

Once again I learn the value of listening...



Bob, after thinking about your observations of heat gain through the FF, I decided to experiment.



Yes, the FF was as hot as the cylinder head. So I bought two longer bolts and 4 thick (1/8") nylon washers. Two insulate the FF from the head (actually intake manifold) and two insulate the shoulder bolts. After a trip into town the FF was HOT. So I installed the new parts and finished my errands in town then drove home (90F). Upon arrival home the FF was cool (!!!!) and the return fuel cooler (hot side) was noticeably cooler (than other identical runs without the nylon washers) as well. Seems some of the heat in the fuel is being picked up inside the FF like you said.



The difference was dramatic.



Hats off to you!!



Keep on posting!!



If anyone else wants to try this I can put together a package of the bolts and washers in case they arent available in your area.

After reading this post I figured it was time to try the spacer Idea.



I used Two M8 x 6CM 1. 20 pitch studs, 8 Hard fiber washers as heat insulators, 4 metal flat washers and two stainless nuts from ACE hardware.

I didn't end up using the Bronze bushings in the photo.



If I want, I can easily stack all the stacers on top of the stud for the cold weather Idea.



Pictures if you care to look.

JJ



studs and washers



Install



Done

 

[Texas Diesel]

Looks good and great pictures! I bet the fiber washers will hold up better in the long run than the nylon ones.



How about mailing me 8 fiber washers? They are what I was looking for but could only find the nylon ones.

 

[jjohn]

Looks good and great pictures! I bet the fiber washers will hold up better in the long run than the nylon ones.



How about mailing me 8 fiber washers? They are what I was looking for but could only find the nylon ones.

I bought all but two of the fiber washers at my local ACE Hardware, however there is a boat load of ACE stores in Colorado.

The number was 3819K on the bin. At $0. 50 a piece their proud of them. I'll check around. PM your mailing address.

JJ

 

[rweis]

In RowJ's post the same 15* rise in tank temp vs OAT.



This weekend the last of the fittings to connect the inline ff (AN-12 to AN-6) will arrive so I can ditch the OEM ff totally (actually I am going to leave the OEM ff mounted in the OEM place, just capped off in case I need it for warming the fuel in the winter). The I will report back on what the differences are, if any, for not having the OEM ff in the system.



I plan to mount the inline ff down on the frame probably to the top of the transmission support cross member to keep it safe and out of harms way.



I have a RACOR 690 right out of the tank for free water seperation and particulate seperation. The inline ff is a 8um 90 gpm diesel compatiable replaceable element filter that will keep the VP safe if anything sluffs off in the fuel system after the RACOR 690T.



More data to come



Bob Weis

 

[Black Beast]

DKNOCH I have a filter and pusher pump mounted back by my tank and when the temp falls below 0 if i do not wrap it in insulation it will jell up on me in about 5 or 10 miles. Above 0 i have not had a problem with out insulating it.

 

[rweis]

Black beast, do you use a fuel additive that has a pour point depressant? If not, wouldn't that give you a lower gel temperature?



Bob Weis

 

[BDanner]

Thanks to Bob for winter reminder!

DKNOCH I have a filter and pusher pump mounted back by my tank and when the temp falls below 0 if i do not wrap it in insulation it will jell up on me in about 5 or 10 miles. Above 0 i have not had a problem with out insulating it.

I just installed a FASS with the filter and had the same thought when I removed the factory filter that has the heater in it and plumbed the fuel line directly to the injector pump.



I think that Bob has the right idea with a fuel additive. 4 years ago we had an extreme series of low teen temperatures here in VA and it was either a coincidence or a contributing factor to a lift pump and injector pump failure at 24,000 miles. Many discussions have been had over cold or hot LP and IP failures. I have a VP44 now on the blink, as it does not like the high heat on restarts. I plan on replacing it when I recover from the $tart of ice hockey season for my 2 boys. Who knows when they die, usually at the worst time!!





My 2 cents is treat your tank with anti-gel additive and do not rely on the fuel stations for what they call winterized #2 fuel.



Another idea that came to mind is this, if truck is to be plugged in to A/C for the block heater go ahead and wrap those rear filters or pumps with that thermostatically controlled heated pipe wrap from your local hardware that is sold in varying lengths. Tape them on with that reflective heat tape that is in the same aisle or the ever useful pull ties.



Bruce in Northside VA__________