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

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R-N-R said:
How about 1/2" thick industrial chemical/weld proof floor mat? It is pricy at about $20 for a 1'x3' section, but it will compress a small amount and should provide some some insulation. There are also less expensive versions of the mat.



Would have to be very thin to keep the helical cut drive gears in proper alignment.
 
Throwing out an idea, what do you think?



The copper front fuel cooler did not measure up to enough temperature drop (was - 3*).



Put a bilge blower (4") powered off the battery by a relay triggered by the ignition on with a Flex a Lite 4109 (9000# 2 1/2" x 3/4" x 20") INSIDE the 4" hose (mounting to be determined).



You get positive pressure OAT at all times, traveling or stopped in traffic.



You could turn off the blower when the fuel did not need to be cooled.



You could mount it anywhere because you are taking the OAT air to the cooler instead of the cooler to the air flow.



Ideas?, comments



Bob Weis
 
I just returned from an extended Christmas trip. The copper tubing cooler looks good... but there is one design problem I can see with it. Fuel will flow through the path of least resistence... which looks like it would be directly from the inlet to the outlet without going through the cross tubes. You need to divide the "tank" on the inlet and outlet side to force the fuel to flow through all the cross tubes... or relocate the inlet/outlet to be on opposite sides so the fuel will flow through the cross tubes. You are not getting any where near the potential out of the cooler the way it is presently designed!



In the original design of my cooler, I put a plug in the tank on the inlet/outlet side of the cooler to force the fuel to flow to the other side of the cooler an back. However, I could tell by touching the cooler that it was transferring quite a bit of heat across the plug. That is why I cut the tank into two pieces... to eliminate heat from passing directly from the inlet side to the outlet side.



If the cooler helped a few degrees as it is, I think that if you can modify it to force the fuel to flow through all the tubes, it will help even more!



Steve Keim
 
The picture did not show it very well.



The outlet at the top comes fully from left to right without any breaks. Where the left to right top tube meets the verticle tube is only a cap off of the verticle tube, but the horizontal tube is soldered to the cap for structural stability. It does force the fuel to traverse across the cooler.



The fuel enters the lower right and exits the upper left, just the upper left tube is extended all the way across to the right for ease of both connections on the same side.



I can see the thermal effect of the tubes. Above 45 mph I see the fuel inlet temp slowly start to drop. The VP44 EBC follows the drop linearly. However the drop is only ~ 3* after an hour of constant speed on flat terrain.



Hence the different approach of puting a fuel cooler with fins inside a forced air (OAT) tube. Will work regardless of the forward speed (ie stuck in traffic, driving at city street speed, waiting for someone in a parking lot).



Bob Weis
 
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From Fleet Owner magazine, December 2005



Cool fuel

by SEAN KILCARR

Dec 1, 2005 12:00 PM

AJP Manager: Jim Caudill



An article about a truck- stop chain that heated fuel before it was delivered — resulting in complaints from drivers about vehicle performance — led technicians at AJP to think about the impact of temperature on fuel economy. They realized that both outside air temperature and the engine-fuel return could transfer heat to the tank.



By monitoring fuel tank temperatures, “we learned that as fuel gets warmer, its efficiency drops; as it cools down, fuel economy improves,” says Caudill. “We found that our fuel temperatures reached 110°F to 140°F. in the summer. Since optimum temperature is around 70°F, we thought we could really see some fuel economy benefits if we could cool our fuel down,” he adds.



The fleet tried a variety of aftermarket fuel cooling systems, but was disappointed with the results. Since most of them used coolant to lower fuel temperature as it comes off the engine, AJP decided to develop a system that cooled the fuel as it left the tank.



Their method uses “separate radiant coolers to radiate the heat off” and also forces air through the cooler, “to get an even greater temperature drop,” Caudill explains.



Bingo. The new system yielded a 10%-15% improvement in fuel economy. “Improving fuel efficiency by 10% across-the-board for our fleet is a big deal, since we ran over one-million miles last year,” Caudill points out. “[The system] also adds negligible weight to our trucks, so we're not losing anything by [using it]. ”



The fuel-cooling system works equally well on old and new systems




interesting,



Bob Weis
 
From Fleet Owner magazine, December 2005



Cool fuel

by SEAN KILCARR

Dec 1, 2005 12:00 PM

AJP Manager: Jim Caudill



An article about a truck- stop chain that heated fuel before it was delivered — resulting in complaints from drivers about vehicle performance — led technicians at AJP to think about the impact of temperature on fuel economy. They realized that both outside air temperature and the engine-fuel return could transfer heat to the tank.



By monitoring fuel tank temperatures, “we learned that as fuel gets warmer, its efficiency drops; as it cools down, fuel economy improves,” says Caudill. “We found that our fuel temperatures reached 110°F to 140°F. in the summer. Since optimum temperature is around 70°F, we thought we could really see some fuel economy benefits if we could cool our fuel down,” he adds.



The fleet tried a variety of aftermarket fuel cooling systems, but was disappointed with the results. Since most of them used coolant to lower fuel temperature as it comes off the engine, AJP decided to develop a system that cooled the fuel as it left the tank.



Their method uses “separate radiant coolers to radiate the heat off” and also forces air through the cooler, “to get an even greater temperature drop,” Caudill explains.



Bingo. The new system yielded a 10%-15% improvement in fuel economy. “Improving fuel efficiency by 10% across-the-board for our fleet is a big deal, since we ran over one-million miles last year,” Caudill points out. “[The system] also adds negligible weight to our trucks, so we're not losing anything by [using it]. ”



The fuel-cooling system works equally well on old and new systems




interesting,



If you use Google search with "Dana fuel cooling" there is an article from Dana corporation at the end that talks about the need to incorporate fuel coolers into production line manufacturing because of the weight / high horsepower of today's vehicles.



Bob Weis
 
And all this time we thought you were just plain ol nuts :-laf





Seriously, it will be nice to have some documentation for what we are doing. I dont know about you but I have received a few "what for?" and "why?" questions from other people. Now I can "legitimize" my fuel cooler and FF thermal insulation.



Good find Bob!
 
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FlexaLite 4109 (2 1/2" x 3/4" x 20") ordered (backordered actually) from Summit. 4" duct from HD. 4" blower from West Marine. Now where to mount it?



Take the air to the cooler rather than take the cooler to the air.



Will take pics and show mounting and temp changes when mounted.



Bob Weis



IF the concept proves out, then some sort of return fuel cooler mounted inside forced air ducting?
 
"FlexaLite 4109 (2 1/2" x 3/4" x 20") ordered (backordered actually) from Summit. "



Did more checking in Summit online catalog. Changed order (about same total $) to a Deralie 13223 (1 1/2 x 1 1/2 x 12 (AN-6)) plus Deralie 13221 (1 1/2 x 1 1/2 x 17 (AN-6)) (Total of 12" + 12" + 17" + 17" = 58" finned). The 13221 before the transmission crossmember on the inside of the frame from the transmission crossmember to where the frame starts to curve up by the starter, the 13223 between the lp on the frame (my relocation) and the fuel tank going aft. I am going to try it passively first without the blower and 4" hose. I hope it will cool the return line the remaining bit to keep Vp input fuel = OAT. 3* more killed, see below. IF it does not kill the return heat, then I will relocate both coolers so they can be put inside the 4" hose and the blower put in the middle longitudionally between the two coolers (17" cooler inside the hose, blower, 12" cooler inside the hose (sucking over the 17" cooler, blowing over the 12" cooler)).



Remember the finned tube cooler I had on the front frame crossmember that sloshed and trapped air? I moved it back to where the H7B is mounted, fit perfectly. It is on the return line from the Vp to the tank (Since it is in the return line it doesn't matter if it sloshes or not). Cools the return fuel 3*, a little bit more heat killed.



I took a really good look at the return line from the T to the frame. There is about 4" of metal line that I can get a AN-6 hose onto to start running it to the frame coolers (see above). Temperature is not a problem, but I have to decide about the possible pressures. In "tanks, lines, and whatnot" Bill K said he measured 0 - 6 psi & 30 gph. However, the Overflow valve is in the VP vane pump medium pressure section where the pressures are 11x - 26x psi (I am recalling from memory). Dumping a small amount (out of the Overflow valve) into an open ended line is what drops the psi drastically, I think.



I have the fuel temp in pretty good shape going into the Vp UNTIL the VP return starts heating the tank volume. The Deralie's should get the return fuel down to OAT. IF the Deralie's get the return down to OAT, then I am going to remove the copper tube cooler. For now, I am going to leave the copper tube cooler until I get the whole fuel system temperature stable at OAT.



I have a Smarty on order and am really looking forward to trying the fuel saving program. I know the overhead computer is not accurate, but I use it as a "this is what it read, this is what it reads now" comparison. Should be interesting, reads now 1375 rpm (about 200 rpm AFTER the ETC shifts into O/D) (51 1/2 mph) flat, empty, 29 - 30 mpg. Cool fuel = ??



Bob Weis



Oh, almost forgot. I ordered a high temperature thermal blanket (like the super charged racers use over their starters to protect the starter from the extreme engine heat) to put between the Vp44 and engine block to stop engine block heat transfer to the VP44. The blanket will be here this friday. I will report back on what difference that makes, if any.
 
Sears Model 50499 058*F - 1500*F (I wanted to check the turbo temps (to check the thermocouple accuracy) also as to why I got the wide range one)



Drove to town today 80* OAT fuel into VP44 90* VP44 EBC 95* but the fuel return to the tank is 96*. I cool the fuel as it comes out of the tank through a H7B w/fan. This afternoon I am going to put coolers on the return to tank line and mount then inside the 4" duct and blow OAT over them (230cfm). We'll see. I will report back after install.



Bob Weis
 
http://www.techinstrument.com/acatalog/Infrared_Themometers.html?Source=googInfraredTemperatureGuns



Egads, which one?



How much was the Sears one? Did you find it in store?



Question #2, what do you think about reading fuel tank fuel temp through the poly body?



Question #3, what did you finally end up doing with your fuel filter?



Question #4, we will be though Winterhaven on July 13th ( +/- a day). Can I pickup the copper and needed parts/fittings/beer and knock out a cooler like you and Steve have?



Edit: I want to make two coolers, one for each truck, but I can make one at home after I see you make the first.
 
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Well, we have a use for a temp checked at work, so I let them buy it, ~$150 as I recall. Ordered on line from Sears, not available in stores. I am a network admin and have found over the years that before total failure of computer components they will increase in thermal signature significantly.



We routinely shoot the CPU's, memory strips, fans, any components with heat sinks, hard drives especially. If it is running out of temperature signature, the technician changes it no question.



Shooting the poly body sucks, however it is all you have for the mass of fuel. And like most readings it is the difference from previous shootings. I think the most important reading is OAT since I base everything else off difference from OAT. I do have fuel fittings very close to the exit from the tank so I use those as much as I use the poly body.



First is the RACOR 690 Free water seperator and (10um) filter, easy to shoot.



Next comes the H7B w/fan. Shoot the input (from the RACOR 690) and the output for cooling across the H7B.



Next comes the RASP and I can shoot the input and output temps from that fairly easily.



Next comes the front copper cooler and that is easy to shoot.



Next comes the inline fuel filter (8um) again easy to shoot.



Next comes the VP input temperature sensor.



Next is the VP44.



I am working the following:



From the engine T to the 2 Deralie coolers mounted INSIDE 4" ducting with a blower (230 cfm) so I get cooling even when stopped in traffic or driving around town. Let me tell you, it is a slight feat to mount the coolers inside the ducting and get it all well bolted down and very stable mechanically. I worked 6 hours today to mount the blower, initial test fit of the coolers, mount the ducting on the blower and mount the first cooler inside the duct, get the fuel line right between the two coolers, mount the second cooler inside the duct. I have to keep the truck drivable so I stopped with working the fuel line from the engine T tank return to the first cooler.



Then will be the second cooler to the finned tube cooler that is back at the back just before the fuel filler line, that I use to have up at the RASP that was too sloshey. In the return line I do not care if it is sloshy or not.



Then see if it was worth it or just a dead end with no value (I hope not).



OH, the OEM fuel filter is gone. I use the RACOR and a 8um inline. IF I lived in cooler climate then I would leave the OEM in place and plumb it in in the fall and plumb it out in the spring. Ball valves come to mind for a permanent installation.



Sure we will build it specific to your truck. You may have something in a different place than I do. I takes about 6 hours to make it and plumb it. Do you have an lp in the stock location? Do you have the OEM ff? Banjo's or an-6 fittings? I need DETAILS EXACTELY so we will have the right fittings on hand. One wrong assumption and it will not connect correctly. Call me and we will discuss it all 863-318-9636 I have VoIP so there is zero additional charge for long distance from me to you (in north american continent).



By then I might have a better solution than a 3* drop (I have something else in mind, simpler, same plumbing, and more cooling).



Bob Weis
 
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I ordered one tonight finally.





Good info on the thermal signature increasing on end-of-life components.



Sounds like a log may be in order. I know wheel bearings will get hot right before they fail too.
 
Bob, look at page 98, paragraph 2 under "applications". Do you think we could be having heat induced bubbles that are causing the rapidly and widely varying FP that some have seen?
 
Today I put a diper on the VP44 and got excellent results!



Today I put a racing thermal blanket (normally used for starters to keep them from being overheated by huge engines) around the VP44. It dropped the low speed EBC by 5* and the high speed EBC by 10*. Good results indeed.



Trying to put the blanket around the VP44 was like trying to thread the eye of a needle with your feet. The blanket is high temp foil on one side bonded to about 1/8" high temp thermal barrier on the other side. It was a real challange to get it to go behind the VP44 and between the VP44 and the block. There is the APS cable in the way, the camshaft position sensor back there, the rear mounting brackets of the Vp44 and then up between the VP44 and the power steering pump, and of course the VP44 input fuel line.



It turned out that the length and width of the blanket was just about perfect. The blanket is from Design Engineering Inc part # 010402 ($32), the Versa-Shield, 7" x 24" that protects up to 2000* Radiant Heat. The 7" x 24" size just fit the VP44 in width and length, and actually pretly nicely (I left a large amount of slack under the Vp44 to be snugged up later).



What I found out is the VP44 is extremely close to the engine block on the back side. Of course the block is about coolant temp of 180* + and therefore it radiates heat into the very close and cooler VP44 (remember WE are trying to COOL the VP44, not HEAT it).



As soon as the radiant heat from the engine was blocked it was obvious in the input fuel readings and the EBC readings. The return fuel temp to the tank also dropped. More on that aspect later.



I would highly recommend a thermal barrier like the Design Engineering. However, remember I also have a blower that supplies 230 CFM to the VP44. Without the blower it might not be as dramatic a temperature control. I have the blower air now captured under the thermal blanket, which works well for me, but you have to assess your particular installation.



In a previous post I mentioned I was going to work on the return fuel temp. I have mounted 2 Dralie fuel coolers (17" & 12") inside a 4" duct connected to a second blower. I will get that hooked up this weekend I think. That should be the end of the VP44 cooling effort. With the thermal blanket installed the VP44 temperatures were almost acceptable. With the additional coolers I should have the VP44 input fuel and EBC temps down to OAT, the origional goal.



I will run the thermal blanket only to get some data the rest of the week and will report back. I drove about 80 miles tonight, 30 at 1400 rpm (51 mph), and 50 at 1800 rpm (65 mph) to get a more realistic data set. The "normal" increase in temperature of 5* due to higher RPM's was reduced to about 2*. Again most of the heat rise due to the engine block heat.



When I shutdown at home the "typical" 15* rise from input fuel to return fuel temperature (before the blanket) had changed to ~2 *. I will take more readings in the next few days to confirm the values.



More Later,



Bob Weis



edit:

1. I thought the VP44 was adding 10* - 15* to the input fuel temp because of the "work" (fuel pressurization etc) it was doing. I will take input and output readings, but now I think most if not all but a few degrees was due to engine heat transfering to the VP44.

2. The concept of engine heat soaking the Vp44 after engine shutdown is even more pronounced that I first thought. I know what the rate of cooling was before the heat shield. I will gather the after engine shutdown heat signature of the VP44 now. I bet the 2 hour cooling requirement I had been using will be significantly reduced.

3. If the heat shield makes as much difference as I think, cooling the fuel is simplier as well. You can use a MUCH simplier fuel cooling system because there is not as much of a temperature rise you are working against.
 
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Texas Diesel -



I think that is why the Overflow valve has the "bore" channel in it and is mounted high in the physical pump so it can vent air. How much air it can handle?, I have NO idea. However, Bosch put it in there for a REASON.



Might lend creadance to "cooler fuel", fewer bubbles? The diaper made a BIG difference. Simple, passive, one time install (somewhat a pain in the *** to get it around the VP44 though). It will take me a few days to verify temp readings for the diaper.



I am going to "insulate" the metal return line from the VP44 to the engine fuel return T. Hummm, a metal line, running right along side of the 160* - 190* engine block for a distance of about a foot. Sounds like a couple of more degrees temp to dispose of.



I keep thinking "cooler fuel, better lubricity, more stable when pressurized" more like what a fluid pump (VP44) does best.



That little solenoid metering valve (high pressure section) needs the very best operating conditions we can possible provide it. It uses an 18 amp trigger and a 10 amp hold current. That HAS to add heat, and electricals do not like elevated temperatures (resistance varies etc).



I think we are getting real close to "kiling this cat".



IF we can get fuel input = OAT and fuel output = OAT + 2* (diaper) then kill that 2* back to OAT (1 simple cooler) we will have "gotten 'er done". A nice temperature stable closed loop fuel system like it SHOULD have been to start with.



Remove, insulate, or relocate any metal fuel component in the engine compartment. After I get this fuel system stable, I will reinstall the OEM ff and get it so it does not contribute any engine heat to the fuel (another diaper?). We need the fuel heater to be available and as stock as possible for the majority of the TDR members.



Bob Weis
 
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Good thinking. I figured the small bore hole was simular to the "jiggler" in the thermostat, i. e. , purging air, so we are on the same track.



Since I have a stock location mounted FF (but using insulating washers) I will obtain some thermal blanket and see how much radiate heat is absorbed with the blanket and without it.



Somewhere I saw some fuel line blanket. It was simular to split loom, just slide the fuel line in the slit and zip tie. It was in a racing catalogue and would do what you are trying. Be aware that it is out there somewhere
 
Design Engineering Inc makes a whole range of thermal products, cover wire, cover fuel lines, cover super chargers, cover starters, cover spark plug wires, cover hydraulic lines, general sizes. Some products are for a set ID and put on when installing the line, some have velcro the entire length (3') and can be installed after the line is in place (this is the one I think I am going to use) and have a range of 1/2" - 1 1/2".



The blanket I got had velcro fuzz in 3 @ 1/2" strips ( 1" in from each side and 1 strip in the middle) the length of the blanket and velcro hooks on a full width (7") tab across one end so you could wrap anything to fit.



I might do the fuel return line from the VP44 the same way. Looks like a really well made product. It is double stiched around the entire perimeter and the velcro strips (1/2") are double stiched for durability.



Bob Weis



I thought I would do a quick summary so far:



A. I would definitely do:



1. I would route the VP return fuel to the tank filler line (or someplace else than the fuel cannister pickup).

2. I would thermal wrap the VP44, ESPECIALLY on the top, block side, and some underneath, if you were not going to wrap the whole thing.

3. Put a thermal spacer between block and OEM ff mounting.



B. I would consider doing:



1. Wrap the OEM FF like Texas Diesel is discussing.

2. Wrap other fuel lines / pumps in the engine compartment.



C. I would think about doing:



1. Fuel cooler(s) back to the tank.

2. Fuel cooler(s) comming out of the tank.

3. move OEM ff completely out of engine compartment.



I'm thinking that if we can eliminate the heating of the engine compartment fuel components (wraping them), and get the VP return fuel away from the fuel pickup that might be enough. Those in northern climates could take the thermal covers off in the winter time. Keeps system OEM except for the VP fuel return, and after the wraps have been purchased, only labor is involved.



No changes totally OEM fuel is about OAT + 50*. I think A only (and this is a WAG) will keep fuel to OAT + 30*(?) (OAT 110* = 140*), A & B above will keep fuel to OAT + 20* (OAT 110* = 130*), A & B & C will keep fuel to OAT (+ 5*?) (OAT 110* = 110*). I would recommed A & B. And we need more data (Texas Diesel) to insure insulating the OEM ff will get about 15* off the system. VP44 wrap ~ 10* (I measured this), OEM FF wrap ~ 15*(Texas Diesel will verify this), return tank line ~ 5*, VP44 metal line to T ~ 2*(I will get data on this in a week or so). Relocate OEM ff 15* (I measured this). Input fuel coolers ~ 10* (I measured this). Return fuel coolers ~10* (I will get data on this). Totals will never be below OAT and might not approach OAT closer than 5* or so (asymtotic?). Like everything it is a SYSTEM approach. No individual thing will do the total job. Each time you insulate or accomplish something you gain a little toward cooler fuel.



Since the VP44 wrap I find the fuel inlet temp and the EBC temp is within 2*. So you can aim for fuel inlet temp and know the electronics bay temp is very very close to that temperature.
 
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