The next best thing to try, is disconnect the HFCM line from your fuel tank outlet (HFCM inlet), and rig up a Gerry can full of fresh diesel fuel with rubber hose to the HFCM. This will tell you if you have a restriction issue with your fuel tank pickup. If you can actually start and run your truck using this temporary connection, your likely next step is to drop the tank for an inspection.

 

So I put a clear hose on the output side of the HFCM and the fuel coming out was foamy. I then pulled off the hose from the fuel tank and turned the key and nothing came out. I talked a couple of people and was told there is no pump in the tank just a pickup. Not sure if they are correct on that. But if there is a pump in the tank does it come on when the key is on? I then filled a jug with fuel and hooked it up to the input of the hfcm and put a tube on the return of the hfcm. solid fuel went in foamy fuel came out. Cracked hfcm?

 

There's no pump in the tank.

Before you get all hyper about replacing a HFCM you need to check the O-Ring on the drain plug and the O-Ring on the filter cap. With the tension on the cap they never back off, but if the O-Ring is nicked or the cap put on improperly you can have an issue, immediately or down the road.

 

I had foaming fual when I damaged the drain O-ring.
After I replaced it all was well.

 

I installed new filters with new O-rings. I will check the one on the drain plug. Yes the HFCM is $360.00. I would rather not pay that. Thanks for the quick replies.

 

Somewhere here in the last year or so we were talking about replacing the drain plug O-Rings on a scheduled basis. Maybe it was when that happened to you Sean.

The ring is an 111 as Mark just posted in another thread, and in that thread there was posted placed to get them cheap. My McMaster note showed several Buna versions, 100 for under $5.

 

Just because you installed a new one doesn't mean you didn't nick a new one.

 

What I was trying to drive at, was a restriction from the tank. That's why I suggested you connect a rubber hose to the inlet side (the side facing the rear of the truck coming from the tank sender) of the HFCM to see if the fuel system would prime back up and start running again.


By doing this, you would determine whether or not you have a restriction inside the tank. I have personally seen rubber debris coming apart to pieces before inside the tank, clogging up the pickup before and causing a no-start type scenario.


As already posted above, there is no in-tank pump. Only the sender and pickup assembly which I'm trying to help you rule out by trying that little test.

 

I did as you suggested. actually the truck did kick a littlebut did not start. I believe the fuel is getting aeriated at the hfcm. I didcheck the O-rings and the one on the drain valve did have a slight cut in it.Just picked up some O-rings and will try in the morning. Thanks

 

Briam you might try also removing the cap pn the HFCM and
ipping it dry out the outside and then set on a dry white paper.
After you get it sitting full with care to see if you have any fuel
leaking out. While this is not 100% proof it can catch some leaks.

The places it can leak air are on the suction side if the fuel tank
supply, The Big cap with the filter and the O-ring for the water
separator drain valve. Not sure but one last place might be the
pump insert where it joins the housing.

How much fuel is in the tank now?

 

The tank if full.

 

Did your truck stop running when this happened to you?

 

Well with a full tank it can't be the little red one way valve leaking.

That valve is on the end of the return line where it exits the pickup
in the tank and is there to help keep air fron going back into the system.
The other issue with low level of fuel is the pickup screen it's self can
get blocked and then pull air in around the point where it connects to
the pickup line where is joins the rubber food screen assembly.

I know that this in now what you have going on but if anyone wants to know why
I asked they can see what I was talking about in this photo.




You can see the little red on way valve and right behind it on the black pickup foot
you can also see the suction relief if the pickup food is plugged up and the pump
is trying to still pull fuel. If the level is below that point it can suck air that way too.
That is the reason why I asked how much fuel you had in the tank.

Other places that might be worth checking are the fuel suction line at both ends
if the replacing of the drain valve O-ring does not help.

What I am thinking is if you still have foam then into a clean container so you
can just dump it back into the tank. Reach up and wiggle the connections at each
end and note if the foaming lessens. There is a seal in the connector that could
go bad. You can see the seals in the connector I have from all the parts I have
hanging out in my pile of old parts. (Life as a Packrat).





The ones I am thinking of are the whitish yellow and the greenish blue ones.
Not sure if they can be replaced or not. I would also check the full run of the
suction side of the fuel line for any rubbing. Just takes a pin hole.

 

Sorry I missed that question.

Not bad enough to stop be it was close. It was not a happy truck.

 

Bubble test passenger side


Bubble test drivers side