Fuel Filter Unit help

[ultim8gamr]

I have been having problems with startup of my M1008. after just sitting for and hour and a half this morning it would not fire up and run. I had to keep cranking the engine over, I did wait for the starter to cool and didnt run it too hard. Finally it started. I have been having fuel startup problems since i bought the truck last month so today i replaced the fuel filter. After replacing the filter I opened the vent on the top to get more fuel in it and all the air out. Fuel was dripping/pouring from between the filter and the filter unit. I dont know where exactly it is coming from, but i did notice it squirting out from the drivers side of the unit coming from between the filter and the unit. What could it be that is wrong? Is there a common part that needs to be replaced? I need to get this fixed ASAP. Any help is greatly appreciated.
John

 

[devilman96]

Post pics plz... were of the visual sorts.

 

[ultim8gamr]

picture the fuel filter looking at it from the grille with fuel running from it. Sorry i dont have any pictures, i dont thinks they'd provide a very good picture in this case. I waited a few hours and replaced the filter just now and it seems to work without leaking. i tried adjusting some of the lines (input and output) to make sure they were sealed where they connected to the fuel filter unit. I still dont know for sure whether or not it fixed the starting problems. i guess i'll find out tonight or tomorrow morning after its sat for a few hours.
John

 

[acetomatoco]

O rings on the new filter? or doubled up from the old filter...next will be a new fuel pressure switch...see archives... ACE

 

[acetomatoco]

try parking the truck with the nose down... minimizes the drain back if you have a rubber line with porosity... ACE

 

[ultim8gamr]

try parking the truck with the nose down... minimizes the drain back if you have a rubber line with porosity... ACE

I had the truck backed up the driveway the whole time I did all the above mentioned, so it was nose downhill. but now its back to nose uphill. if i have problems later tonight or in the morning i will back it up the driveway and let it sit to try what you said.
John

 

[gasser]

If it's leaking from the drivers side of the base, in between the base and the filter - chances are that it's the STE fuel pressure switch. Its about the size of a quarter, and there is a rubber o-ring that seals it in.

There was a WO back in the early 90's to get them all replaced, but as the story goes, they didn't get done (or only like 20% of the trucks got them done).

You can get them from Owen Exports (http://www.owens-export.com/) for approx $10 each. I would definitely pick up a few; every CUCV that I owned and drove, I had to replace them.

HTH,

-graham

 

[ultim8gamr]

If it's leaking from the drivers side of the base, in between the base and the filter - chances are that it's the STE fuel pressure switch. Its about the size of a quarter, and there is a rubber o-ring that seals it in.

There was a WO back in the early 90's to get them all replaced, but as the story goes, they didn't get done (or only like 20% of the trucks got them done).

You can get them from Owen Exports (http://www.owens-export.com/) for approx $10 each. I would definitely pick up a few; every CUCV that I owned and drove, I had to replace them.

HTH,

-graham

i think i know what you are talking about, as i was wondering what that was. Thanks for the info i will definately check into it.
John

 

[ultim8gamr]

I tried parking it in the driveway withth efront of the truck downhill and it only died faster upon startup. I might try and replace all the lines near the filter unit. but that pressure thing that was mentioned may be what i need.
John

 

[gasser]

It would not surprise me if it ended up being the STE fuel pressure switch. One time it was had an ever-so-slightly leak and the other truck, it didn't leak at all. But replaced them and the truck would fire right up.

Good luck, and you will want to get a couple. Chances are, with the OD green disease, you will end up with another vehicle!

-graham

 

[ultim8gamr]

It would not surprise me if it ended up being the STE fuel pressure switch. One time it was had an ever-so-slightly leak and the other truck, it didn't leak at all. But replaced them and the truck would fire right up.

Good luck, and you will want to get a couple. Chances are, with the OD green disease, you will end up with another vehicle!

-graham

is the fuel pressure switch on the civy units too or just a CUCV thing. it didnt seem to ring any bells at the local Chevy Dealer.
John

 

[CCATLETT1984]

I think that it was in the block style filter on both the civy trucks and ours, although I would doubt that a dealer would remember it unless you get the old timer at the parts desk.

 

[gasser]

is the fuel pressure switch on the civy units too or just a CUCV thing. it didnt seem to ring any bells at the local Chevy Dealer.
John

John, it's just a CUCV thing. This switch is purely a diagnostic tool used with the STE/ICE system. Yeah, I don't think the dealer will know about this. Now, in terms of the base - I am not 100% if the civvy base has the same provisions for such an item - I don't think they do.

You can try to take the switch out and put a new O ring around it, but there is a metal clip that holds it in there. Every time I took out the old switch, that metal ring got screwed up so if I wanted to re-use the same switch, I don't think it would hold in there properly.

HTH,

-graham

 

[ultim8gamr]

yeah how do you get it out? i remember looking at it and tugging on it not knowing what it was, but it didnt seem to move at all. does it just pull straight forward? I guess if i had to i could go over to the civy model unit and avoid future problems with the pressure switch?
John

 

[rdragoo]

I just fixed my fuel pressure switch by eliminating it. It is unique to the military models. I removed the switch and drilled and tapped the original hole with a 1/4 -28 crafstman tap. I then installed a threaded plug in the hole using thread sealer of course. No more leaks..... ever again. No more hard starting from air in the system either.

Randy
Tehachapi, CA

 

[devilman96]

cool idea!

 

[ultim8gamr]

cool idea!

x2. maybe teh route i will take. pretty easy to do? and no spacing conflicts with the filter?
John

 

[Ambulancechser]

fuel sensor...

i assume this is what you have leaking.cool idea to plug it...something to keep in mind.
In case your wondering,this filter housing is one i pulled of an '86 suburban...seems to exist in the civvy trucks as well.with some luck,a scrap yard might have what your looking for.

 

[gasser]

RE: fuel sensor...

Ambulancechser, if that is from a civvy model, then it does have a switch - however GM doesn't list a switch, one that goes into the base like the Mil ones ... so i am not understanding this civvy fuel base then.

 

[Ambulancechser]

it's true...

yup...'86 with a 6.2.same truck i got my used hood from.

I remember reading somewhere that on the civilian trucks,the fuel pressure switch would signal a fuel restriction...ie: a plugged filter.seems that the pressure switch and the water sensor were both wired to the WIF light in the cab...thus the WIF light would pull double duty as a water in fuel indication and plugged filter indicator.Can't be certain of this however.if true ,this would be typical GM sillyness...yet another reason to change to a racor setup.

This could be the reason behind a few stories iv'e heard locally of owners getting a wif signal light,draining what they thought was water,and still getting a wif light...they change the filter and the light goes out.Have they drained water,or eliminated a fuel restriction?who knows?

I think i have another filter housing or two laying around...i'll check those and see if the switch is present.just to check if this one isn't an anomally.