VP44 PSG fuel cooler ideas

[KATOOM]

I dont want to railroad an awesome thread but I'd like to touch on the topic of fuel cooling via a fuel cooler of some sort.  I just have this crazy premonition that there needs to be a fuel cooler on these trucks.  Given what I recently experienced while towing a very large trailer in 100*+ weather uphill with the engine at 215*-220* and having the throttle do something unexpectedly weird, excessive fuel temps or just plain excessively hot PSG is becoming very likely the culprit of what happened.

 

I'm going to be digging into this topic really heavily and searching for an optimal small radiator to mount somewhere under or in front of the truck.  Possibly with a fan assist too.  There is just too many other trucks/diesel vehicles utilizing a diesel fuel cooler.

 

In saying that, I've wondered if anyone has ever considered trying to cool the PSG itself.  Chip from Bluechip told me around a year ago that Bosch has implemented thicker heat sinks under the PSG but I can’t confirm this and he's not around anymore.....that I know of.  Then I got to thinking about a Peltier Module.....  Why hasn’t this been considered?????  Maybe it couldn’t offset the heat dissipation needed but I think using a $20 Peltier Module and sticking an aluminum bladed computer CPU heat sink to the top of it would have to help.  Here's a video of what this device is if someone doesn’t understand what I'm talking about. https://www.youtube.com/watch?v=9Cuh2msd2lo If someone was so inclined they could install an inline thermostat too so it didn’t run in the winter.

 

Maybe this would be better served in another thread but I think its a topic which needs to be revisited again.....

[Yankneck696]

After pondering, I do not think that the lift pump is creating too much heat. It is all either conducted from the engine to the IP and/or in the IP (Friction, pressurization & computer).

That said, at the moment, a cooler on the return line & the fullest tank possible may help in this area.

 

Ed

[Mopar1973Man]

I'm going to be digging into this topic really heavily and searching for an optimal small radiator to mount somewhere under or in front of the truck.  Possibly with a fan assist too.  There is just too many other trucks/diesel vehicles utilizing a diesel fuel cooler.

 

 

Take a peek under about a 2006 or so Duramax and see how they made there fuel cooler but you won't be happy. It will work but if you drive in the mud at all it will plug the cooler up.

 

I dont want to railroad an awesome thread but I'd like to touch on the topic of fuel cooling via a fuel cooler of some sort.

 

Topic split for you...

 

[TFaoro]

When I bought my truck is had a small fuel cooler in front of the radiator. It just looked like a minneature transmission cooler. I removed it due to a weak lift pump, but I can post pictures of what was on there if you would like

[Yankneck696]

Tyler, was it on the feed or return side?

 

Ed

[JAG1]

Interesting, You could use the Peltier module in frigid temps to warm the fuel too.

[Yankneck696]

The computer would need to be removed, milled flat, heat sink grease applied, heat sink to the other side & still not enough fuel flow to remove the heat, in my opinion. I tried a Peltier intercooler once 12 triple stacks of them on a funky heat sink system, then just chilled coolant with the AC compressor & used a water to air intercooler. It was a fun experiment, though.

 

Ed

[KATOOM]

Mike, I agree as I dont think mounting any cooler in a vulnerable location is a good idea either.  And it seems mounting it up front and away from any drivetrain secondary heat interference would be the most logical since were after fuel temps at around 100* at the highest.

 

I'm really serious about this guys.....  I've been delving into the subject and I'm amazed at the information I've run across so far.  Diesel fuel coolers are ANYTHING but uncommon.  Its seemingly more uncommon to NOT have them but yet we see throughout the years that OEM is always cutting corners so if they can get around something which "may" not be needed then your vehicle will come without whatever device that may be.  And the reasons for the diesel fuel coolers is always in regards to injection pump reliability.....but then tends to take a turn and spawn into a discussion about the density of fuel and HP and fuel mileage.

 

And another very interesting subject which I found resulting in looking for coolers was algae.....  Just as we regularly talk about oil "cokeing" in the turbo bearing from excessive heat, there is a situation called "asphalting" the fuel whereby diesel fuel is over heated and literally cooked to the point of thermal separation which results in a black tar like substance that’s prone to collect in the fuel tanks and fuel filters…..which is unknowingly categorized as algae from water and debris contaminants.  A topic more discussed in class 8 type trucks but apparently or potentially a plaguing problem slipping under the radar for lighter duty diesel forums.  We all know how hot the fuel can get in these injection systems so it must be something the diesel engine industry is aware of since as I mentioned before, the number of diesel engines with a fuel cooler is higher than those without.

 

And in regards to "where" to place the cooler.....  Well after the tidbit of research I've done, the return line is the general location based on trying to reduce the fuel temp before its dumped into the fuel tank, but there is plenty who mounted theirs on the inlet side before the injection pumps.  And since I'm after maximum fuel heat dissipation just before the VP, I think mounting a tranny cooler with an electric fan as close to the VP as possible yet remaining in front of the radiator, is where I want to do this.  That said, I may also place a secondary smaller less BTU rated flat cooler on the return line side mounted to the frame and up away from debris.  Just to offer some additional offsetting of heat coming off the VP and head line as it flows back to the fuel tank.  Remember, the fuel module has both the inlet and return line dumping directly side by side into the basket which means the hot return fuel is most likely being sucked right back up into the supply line.  Keeping fuel in the tank at all times is the only way to combat this as sloshing fuel should counter affect but you can see under high fuel demand where this would be a problem.  That is unless you have fuel coolers…..

 

I'm also wanting to install a couple temp gauges via two 1/8” port fittings, maybe a dual temp gauge from Westach, so I can watch the supply and return line temps and see whats going on while driving.  Like I have time to watch more gauges…..  The only problem is I'm running out of (ran out of) places to mount gauges and I dont want to clutter up the cab with silly gauges mounted in various obnoxious manners for sake of research.

Again guys, if you think this is a waste of time, do a few various and simple Google searches for things like diesel fuel coolers and you’ll find a plethora of applications and discussions.  Its not a very “knowledgeable” topic as people tend to overlook the true reasons for the purpose but nonetheless, when you run across the guys who understand whats going on then the lights bulbs start illuminating and you realize that this is something these VP truck MUST have…..

[Yankneck696]

Well thought out. I have never really seen an issue of algae mentioned in our trucks. When I was a marine mechanic, we used to install Algae X systems (Rare earth magnets in fuel system & a catalyst liquid) & was AMAZED at the cleaning effect of them. The algae in diesel systems actually breeds in the layer between water & diesel fuel. It's a funky little critter.

 

Ed

[KATOOM]

I honestly can’t comment on the algae issue for these trucks either.  Although I have seen the algae topic tossed around before but I never saw reason to be included.  Maybe now I will and see if there's any connection to heat.

In saying that, I do know people with other diesel trucks and especially one person with a 7.3 Ford who has suffered from a tank so dirty that he had to have someone drop the tank and clean it out.  Now I know this person fills his diesel tanks at all the places located in this small area where I fill up so unless he happen to tap into a fuel station who did nothing but pump dirt in there, I think now that his dirty tank issue may have been part of what we're talking about.  He tows some heavy equipment on a regular basis with this truck and I can speak from experience when driving with him that this truck gets HOT when he's towing things.  Maybe a connection.....?

[rancherman]

I've got  algae problems..  you bet!    It  starts  in  our fuels  that are carrying  more  suspended  H20  these days.      I'll  say  it  rears  its  ugly head  on  my tractors...   the ones  that  are running  balls  hot all day,  and  are shut off,  with very little fuel in the tanks..   when  they cool off,  it'll draw  cooler  moist air  during the night,  which of course  condenses even more water  in the  fuel tank...   I'll  'shock treat'  my fuel  2x  a year,  and     it  plugs  my   tank filter immediately.... but  haven't had  problems  downstream since.   going on 5 years now.

I was told  that the algae  grows  along  the  lower part of the tank, part way up the side. (during the summer)   winter  rolls around,  and it   breaks it  loose... guess what?  yep,   nightmare from hell.

My  1000 gallon tanks  are not  isolated  from   atmosphere  either,  they  are  wheezing  outside air  day after day... they are above ground,  in the sun.

you guys  are buying fuel  from  underground  storage,  and   should be minimal  temp swings..    great for you!

 

It's  good  practice  to top off the  tank  at the end of  a long run,  before  it cools  down,  no matter  what the vehicle.   I'm  lazy, too tired,   or too far from the  barrel to do it  all the time!    I'm in  an area  where humidity  isn't too bad..   western  guys  are even  less  prone  to  this problem.

 

As  far as  cooling  the   computer on the  '44,   one needs  to  isolate  where  the  heat is coming from first.    Heat soak from the engine,   the  high pressurization of the fuel itself,      the computer  itself???   Or  all of these  compounded??

I    have many  tractors  with  bosch inline style  pump  I  CAN   grab the individual  lines  in my hand...   so  I can't  think  the  injection  pressurization is  building very much heat...In fact,  I'd rather  touch the lines  before  putting my hand on the side of the block!

Perhaps  the  computer is  covered too well,  and  that alone is  holding heat?

 

Maybe  the  bad heat  is  coming  AFTER  shut down ??   everything  heat soaks??     besides  my  injection lines,  the  pump itself  doesn't  'feel' as  hot as the  engine block.

 

I'll borrow my neighbors  temp gun,  and  point it at various  spots,  anyone else  out there  can sure report  findings too!

Edited August 6, 2014 by rancherman

[KATOOM]

Valid points rancher but we already understand that heat "soak" after shutdown is a problem.  Which is why others have tried to come up with devices or ways to run a fuel pump after the engines shut down for a set period of time.

 

With that said, I'm not address the heat soaking problem at this point since all I'm after is a reduction of fuel temps while running.  Having the ability to read fuel temps are limited to a few people with very high dollar scanners or some Edge chips which monitor fuel temperature.  Others who care have resorted to laser temperature thermometers.  Either way, all have found very interesting data and repeatedly read fuel temps in the 150*+ range.  That’s HOT and even if you have a constant supply of fuel pumping into the VP, combine running heavy long uphill grades in triple digit summer heat with the engine coolant peaking in the 220* range, the VP is going to get hotter as well and the fuel temp will rise or loose its ability to dissipate enough heat if its already being delivered in the 140*-160* range.  Dropping the fuel temp coming into the VP down to ambient levels will HAVE to have an affect…..

 

Yes, the electronics are most affected by heat soaking but who’s to say that the problem with the PSG electronics isn’t being additionally aggravated by overly hot running temps in hot weather?  Again, this isn’t something new to the diesel world.  Just for sake of interest…..if you're not bored after the first few pages of posts, here is a couple very deeply involved threads from other forums who addressed this issue many years back to current date.

 

http://www.thetruckersreport.com/truckingindustryforum/trucks-eighteen-wheelers/185639-anyone-install-a-fuel-cooler.html

 

http://www.turbodieselregister.com/threads/135952-Modifying-fuel-system-so-temperature-input-to-VP44-80*-100*-your-inputs?highlight=dead+pedal

Edited August 6, 2014 by KATOOM

[LiveOak]

I dont want to railroad an awesome thread but I'd like to touch on the topic of fuel cooling via a fuel cooler of some sort.  I just have this crazy premonition that there needs to be a fuel cooler on these trucks.  Given what I recently experienced while towing a very large trailer in 100*+ weather uphill with the engine at 215*-220* and having the throttle do something unexpectedly weird, excessive fuel temps or just plain excessively hot PSG is becoming very likely the culprit of what happened.

 

I'm going to be digging into this topic really heavily and searching for an optimal small radiator to mount somewhere under or in front of the truck.  Possibly with a fan assist too.  There is just too many other trucks/diesel vehicles utilizing a diesel fuel cooler.

 

In saying that, I've wondered if anyone has ever considered trying to cool the PSG itself.  Chip from Bluechip told me around a year ago that Bosch has implemented thicker heat sinks under the PSG but I can’t confirm this and he's not around anymore.....that I know of.  Then I got to thinking about a Peltier Module.....  Why hasn’t this been considered?????  Maybe it couldn’t offset the heat dissipation needed but I think using a $20 Peltier Module and sticking an aluminum bladed computer CPU heat sink to the top of it would have to help.  Here's a video of what this device is if someone doesn’t understand what I'm talking about. https://www.youtube.com/watch?v=9Cuh2msd2lo If someone was so inclined they could install an inline thermostat too so it didn’t run in the winter.

 

Maybe this would be better served in another thread but I think its a topic which needs to be revisited again.....

Unless you disable the fuel filter canister fuel heater or bypass it, you would be heating and cooling the fuel at the same time.

[KATOOM]

No you wouldnt because the fuel heater wont start "heating" fuel until it recognizes 45* F and it turns off at 75* F.  Unless this fuel temp is being read inside the VP and not at the fuel filter housing.....

[Yankneck696]

THe fuel heater is not on all the time. Ambient or IAT temp must be below a certain threshold & then once satisfied, turns off.

 

Ed

[Mopar1973Man]

No you wouldnt because the fuel heater wont start "heating" fuel until it recognizes 45* F and it turns off at 75* F.  Unless this fuel temp is being read inside the VP and not at the fuel filter housing.....

 

 

THe fuel heater is not on all the time. Ambient or IAT temp must be below a certain threshold & then once satisfied, turns off.

 

Ed

 

Fuel heater is not controlled by VP44 fuel temp sensor nor the IAT. It's thermostatically controlled within the fuel filter housing.

 

From the FSM...

 

FUEL HEATER

 

DESCRIPTION

The fuel heater assembly is located on the side of the fuel filter housing (Fig. 9). The heater/element assembly is equipped with a temperature sensor (thermostat) that senses fuel

temperature. This sensor is attached to the fuel heater/element assembly.

 

OPERATION

 

The fuel heater is used to prevent diesel fuel from waxing during cold weather operation. When the temperature is below 45 Ϯ8 degrees F,

the temperature sensor allows current to flow to the heater element warming the fuel. When the temperature is above 75 Ϯ8 degrees F, the sensor stops current flow to the heater element. Battery voltage to operate the fuel heater element is supplied from the ignition switch and through the fuel heater relay. Also refer to Fuel Heater Relay. The fuel heater element and fuel heater relay are not computer controlled. The heater element operates on 12 volts, 300 watts at 0 degrees F.

[Mopar1973Man]

Katoom I've got to make you think. Why is it I have summer temperatures of 105-115*F here in Idaho and have absolutely no issues with fuel cooking the VP44? I have no special coolers on my VP44. No blowers, heat sinks, coolers, radiators, etc. Nothing... The only change to the fuel system is AirDog 150 that's it. It not that my truck get light duty either I tow on grades as steep as 16%. Haul either a utility trailer or my RV. Still all done in 105-115*F temperatures. This VP44 has 185k miles and still going strong.

[Yankneck696]

OK, that must be a total misprint, as I surely cannot be wrong..... LOL

I actually should have known that, as the Racor heaters are similarly controlled......

But, I still am not admitting that I was wrong..... ;-)

Ed

[KATOOM]

I really cant answer that mike.  And by no means am I proclaiming to be some savant on this subject but more that its a topic which I feel needs attention.  Maybe your custom fuel timing changes you've implemented are contributing to cooler fuel temps inside the VP.  Thats a shot in the dark but I cant discredit the fact that your scenario is not "normal".

 

Also, maybe you're not building the underhood heat you think you are.  Do you have the ability to read fuel temps?  I cant remember.....

[Mopar1973Man]

OK, that must be a total misprint, as I surely cannot be wrong..... LOL

I actually should have known that, as the Racor heaters are similarly controlled......

But, I still am not admitting that I was wrong..... ;-)

Ed

 

Take notice to the wiring diagram. Upper right corner is the fuel heater.

 

I really cant answer that mike.  And by no means am I proclaiming to be some savant on this subject but more that its a topic which I feel needs attention.  Maybe your custom fuel timing changes you've implemented are contributing to cooler fuel temps inside the VP.  Thats a shot in the dark but I cant discredit the fact that your scenario is not "normal".

 

Also, maybe you're not building the underhood heat you think you are.  Do you have the ability to read fuel temps?  I cant remember.....

 

Neither am I but all I can do is chuck out the conditions and what I don't into the pile and see if brings more information to the table. IAT fooling has nothing to do with fuel temps the only thing I made sure of is 14+ PSI fuel pressure. As long as the overflow valve is open return flow will occur.

 

OVERFLOW VALVE

 

DESCRIPTION

 

The overflow valve is located on the side of the injection pump (Fig. 58). It is also used to connect the fuel return line (banjo fitting) to the fuel injection pump.

 

OPERATION

 

Fuel volume from the fuel transfer (lift) pump will always provide more fuel than the fuel injection pump requires. The overflow valve (a check valve) is used to route excess fuel through the fuel return line and back to the fuel tank. Approximately 70% of supplied fuel is returned to the fuel tank. The valve opens at approximately 97 kPa (14 psi). If the check valve within the assembly is sticking open, fuel drainage of the injection pump could cause hard starting.

 

So with the bold RED statement keeping fuel pressure up above 14 PSI will ensure the flow is continued. So now the fuel tank is your radiator/cooler and with a full tank of fuel it can absorb a large amount of heat before the tank warms up.