Check Valves = Automatic Bleeder

BlackLibertyCRD · **Posted:** Thu Jul 26, 2007 9:58 pm

I am thinking about installing a check valve before the inlet of the fuel head and got an idea that could be an automatic fuel bleeding. Does anyone know if this valve will hold up to diesel fuel??

http://www.usplastic.com/catalog/varian ... 5Fid=64175

Jeger · **Posted:** Fri Jul 27, 2007 8:05 am

Kynar® housing with Viton® diaphragm should be fine

Polypropylene would probably not last long....especially with 130 degree fuel going through it...

Our filter head already has a check valve...what have you got in mind?

Joe Romas · **Posted:** Fri Jul 27, 2007 8:19 am

And it's possible that the slight amount of extra resistance put on the vacuum side may trigger a massive leak and then failure of the pump. Think about drvhard's situation :shock:

BlackLibertyCRD · **Posted:** Fri Jul 27, 2007 5:34 pm

Jeger
Our filter head already has a check valve...what have you got in mind?

I didn't know if there was a check valve in the head but I will check the service manual about that. I know that when I disconnect the line to replace the pre filter all the fuel there runs back to the tank. I'm thinking more like a check valve at the fuel pump low to high pressure side is where the check valve would be. Not much help for a filter that is sitting high.

What I thinking of doing is putting a check valve before the prefilter so fuel will flow from the tank but not back. Since the filter will be under vacuum ond the return hose will will have some pressure, I thinking about installing a line from the replacement fuel bleed valve, and tee into the return line at the rear lower left on the engine. The check valve there would be set so pressure won't flow from the return to the bleeder while the engine is running. When the engine gets turn off, the pressure will release at the return, and pressure will build at the filter from engine heat. this will bleed the fuel thru the check valve through the return line. The check valve before the pre filter will prevent the pressure in the filter from going down the supply line. Then when the engine is restarted, the flow of fuel is back to normal, hopefully with a well bleed fuel system.

Joe Romas
And it's possible that the slight amount of extra resistance put on the vacuum side may trigger a massive leak and then failure of the pump. Think about drvhard's situation

I had the prefilter get restricted a few times and really saved my @ss while long distance driving. One time I know for sure that I got a bad load of dirty fuel fo you can see it in the clogged pre filter. I was abled to quickly change it and go on my way. I can't imagine changing a stock filter at a rest stop with a hot engine in the five minutes it took me with the pre filter.

Cowcatcher · **Posted:** Fri Jul 27, 2007 6:14 pm

BlackLibertyCRD,

Remind us of the where and what of your prefilter.

BlackLibertyCRD · **Posted:** Fri Jul 27, 2007 9:18 pm

Cowcatcher wrote:

BlackLibertyCRD,

Remind us of the where and what of your prefilter.

I used to use a Fram G3 filter right at the inlet of the filter head. I use the short hose and clamps that comes with the kit at the head fitting and the hose that came off of the fitting to the inlet of the G3. Now I use a purelator 3/8 filter that has glass body and replacement element. Will be cheaper in the long run. When I add the check valve, I will have to install a longer piece of hose and loop it to prevent kinking. I don't want to cut the orginial fuel lines in case I have to undo it for warrenty purpose, such blaming mod on breakdowns like a dealer said ORM cause the A/C to fail. :roll:

I don't know how the ORM could cause the low pressure switch to go bad and why it took 3 trys for them to discover it. :evil:

The thing to remember about the fuel system is to have everything operating room clean and make sure there is no leaks.

Cowcatcher · **Posted:** Fri Jul 27, 2007 10:12 pm

Thanks

Jeger · **Posted:** Sat Jul 28, 2007 8:17 am

Put a vacuum/pressure combination gauge on your bleeder valve connection and see what you get after shutoff. Or just open the bleeder valve after you shut it off and see if anything comes out....would help to make sure there is no air in the system already though. If you get a positive pressure/flow then you may have a winner!

Here are some nice check valves if you get this to work...

http://www.microchek.com/html/check_valves_.html

I dont have a clue how much they cost though..

I have thought about connecting a small fuel pump to the bleeder port and tee into the return lines. Have it run for a few seconds after shutoff to clear anything out. Or perhaps there would be a way to use our vacuum pump to accomplish the same thing??? :idea:

BlackLibertyCRD · **Posted:** Sat Jul 28, 2007 4:18 pm

Jeger wrote:

Put a vacuum/pressure combination gauge on your bleeder valve connection and see what you get after shutoff. Or just open the bleeder valve after you shut it off and see if anything comes out....would help to make sure there is no air in the system already though. If you get a positive pressure/flow then you may have a winner!

Here are some nice check valves if you get this to work...

http://www.microchek.com/html/check_valves_.html

I dont have a clue how much they cost though..

I have thought about connecting a small fuel pump to the bleeder port and tee into the return lines. Have it run for a few seconds after shutoff to clear anything out. Or perhaps there would be a way to use our vacuum pump to accomplish the same thing??? :idea:

Thanks for the link, I will check them out also. I ordered the bleeder valve and will be adding check valves after installing it. I have to email Microchek to be sure that these valves can be used with diesel fuel.

Edit: After reading the link to the e-mail, looks like they only sell to O.E.M. :cry:

BlackLibertyCRD · **Posted:** Thu Aug 09, 2007 10:05 pm

I got the check valvas and the bleeder kit and hooked it all up and after 1 day all looks well. Now all I do it open the bleeder valve and pump away until I don't see no more air going through the return check valve. I been leaving the bleeder open and driving it that way. The plan is that when the engine is shut off, the fuel is no longer under vacuum in the filter head and once the return is no longer have pressure, the pressure built up in the head will push any new air out the bleeder and through the return check valve. I will be going from Delaware to Newnan, GA this weekend to pick up a new trailer and will report back if this automatic bleeder works.

jeep06 · **Posted:** Sun Aug 12, 2007 8:22 am

I had to try it yesterday morning before doing my usual bleeding, the Jeep sat all night in the garage, so I wanted to see what happened by opening the bleeder valve before hitting the primer pump. I hooked up my high tech bleeder kit (pickle jar and clear hose..lol) with about an inch of fuel in the jar, stuck the hose in the jar of fuel, cracked open the bleeder and it sucked about 8" of fuel into the hose out of the jar. So must be it is not leaking real bad to still have vacuum in the system after sitting for 10hrs. Just don't understand why there was a ton of air when I did bleed it out after that. Oh well, thought I would share my findings. Good luck with your new auto bleeder. I am thinking about one of the "T" handle valves so it will save me getting out my wrench all the time.

BlackLibertyCRD · **Posted:** Sun Aug 12, 2007 11:43 pm

The bleeder setup works great for bleeding the system. Just pump the plunger and watch the tube until all air is out. It goes through the return for no mess at all. As Jeep 06 found the filter head don't build up pressure but cools down to a vacuum. To make this bleeded system automatic, I will have to add a lift pump. The purpose is to take away the vacuum and bleed the system at the same time. Excess pressure would bleed through the return removing air at the same time. The fuel system really got tested on my way to GA and back to DE. I got stuck in traffic for 3 hours right below Richmond, VA on I-95 and I-85 interchange in 103 F weather. Bad accident when someone lost 45 ft fifth wheel camper and it blocking all but one lane. I towed a 6x12 v-nose Haulmark enclosed trailer from GA to DE and only lost about 35 minutes to traffic jams. I know where to get the lift pump, but wiring it and finding the fittings is another matter. I want to leave all parts to be removed for warranty purpose.

BlackLibertyCRD · **Posted:** Wed Sep 12, 2007 3:50 pm

I expect to get a lift pump tomorrow and will install Friday night. I went with the Facet 40109 and going to mount under hood with quick disconnect in case it don't work well. I expect it will work great but will run all this weekend to be sure.

BlackLibertyCRD · **Posted:** Fri Sep 14, 2007 3:32 pm

I installed the pump last night and ran it so far one day. I noticed that with the key turned on the pump run for 30 seconds and shut off as a safety measure when engine is not running. At the same time it bleed the fuel system and was ready to start the engine. With the engine running the pump stays running with the excess pressure sent back to the return keeping the fuel system bleed at the same time. I don't see any leaks.

The engine runs smoother and responsive. I noticed that the virbration I normally get at low RPM is gone (52 & 62 MPH). When I check for air in the fuel system, there is none. How about that, I am very pleased.

Next I'm going to reinstall the preator chip and ORM then run the P out of it this weekend. If I don't have any problems even with the chip installed and stays air free then the problems I been having is solved. Looks like I found a way to burp this thing for good.

flash7210 · **Posted:** Fri Sep 14, 2007 8:21 pm

Dude, I love ya and I know you are a smart guy and I'm glad you've
had great success with your fuel system mod...

...BUT GIVE US SOMETHING TO LOOK AT!!!

I'd even settle for for a drawing.

BlackLibertyCRD · **Posted:** Sat Sep 15, 2007 12:01 am

flash7210 wrote:

Dude, I love ya and I know you are a smart guy and I'm glad you've
had great success with your fuel system mod...

...BUT GIVE US SOMETHING TO LOOK AT!!!

I'd even settle for for a drawing.

I would like to test this at least a week before I recommend anyone doing these mods. This weekend I will drive it hard. I already reinstall the predator chip and redone the ORM and it runs great. Next weekend I have a trip from New Castle, DE to Pocomo, MD and and I may have a chance to really open it up to be sure no problems. Ifall goes well, I will start a new thread with the list of parts, how to install with pictures. The total cost is less that $100.

flash7210 · **Posted:** Sat Sep 15, 2007 7:29 am

Cool

retmil46 · **Posted:** Sat Sep 15, 2007 10:36 am

Two quick questions -

Can fuel still flow thru the pump if it quits for some reason - ie, did you try running the engine with the pump installed in line but no power to it? If not, might want to consider putting a check valve bypass around the pump, so that if it does quit for some reason the fuel system will still function as a vacuum system and you can keep running until you can pull over someplace and remedy the situation.

I've had the experience of traveling down the road at 50 mph and have the engine just flat out shut off due to a clogged fuel filter. Whether due to a clogged fuel filter or a lift pump that decided to quit working, believe me it's something you'd rather not experience.

Did you keep your prefilter, and have it ahead of the pump? On the other diesel forums and websites I've checked, the most common cause of failure on a positive displacement type lift pump was not having a prefilter ahead of the pump and trash in the fuel jamming it up.

BlackLibertyCRD · **Posted:** Sat Sep 15, 2007 1:20 pm

retmil46 wrote:

Two quick questions -

Can fuel still flow thru the pump if it quits for some reason - ie, did you try running the engine with the pump installed in line but no power to it? If not, might want to consider putting a check valve bypass around the pump, so that if it does quit for some reason the fuel system will still function as a vacuum system and you can keep running until you can pull over someplace and remedy the situation.

I've had the experience of traveling down the road at 50 mph and have the engine just flat out shut off due to a clogged fuel filter. Whether due to a clogged fuel filter or a lift pump that decided to quit working, believe me it's something you'd rather not experience.

Did you keep your prefilter, and have it ahead of the pump? On the other diesel forums and websites I've checked, the most common cause of failure on a positive displacement type lift pump was not having a prefilter ahead of the pump and trash in the fuel jamming it up.

http://www.facet-purolator.com/solidstate.asp

I picked the pump that don't have a anti-siphon valve and is a not a positive displacement pump. That means that the fuel can be siphon through it. I made sure by blowing through the inlet and sucking through the outlet. I has it's own check valve so you can't blow through the outlet.

Facet recommends using a 74 micron filter before the pump. I recommend a prefilter anyway and that is a goog place to put it. A G3 fram filter saveed my @ss from a bad load of fuel while on a cross country trip. I was abled to change it at a rest stop in five minutes. I can see the filter was full of junk and was hard to blow through. I have since replaced the G3 with a Purolator 3/8 inline filter that can be taken apart and cleaned and has replaceable screens if your not near an air sourse to blow it out.

nescosmo · **Joined:** Sat Jul 14, 2007 11:17 pm **Posts:** 202

I thought that you had some pics for us. Will love to do what your are doing but I am not that smart like you.

Please give us some pics and parts #.

Thanks........Nescosmo.

Check Valves = Automatic Bleeder

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