Ford Truck Enthusiasts Forums

Ford Truck Enthusiasts Forums (https://www.ford-trucks.com/forums/index.php)
-   1994.5 - 1997 7.3L Power Stroke Diesel (https://www.ford-trucks.com/forums/forum170/)
-   -   Big Fuel Injection problems, need help quick! (https://www.ford-trucks.com/forums/1329119-big-fuel-injection-problems-need-help-quick.html)

desertdogs 08-05-2014 09:16 PM

Big Fuel Injection problems, need help quick!
 
Hey guys, you're all so knowledgeable on this forum I know someone will have some answers for me. I had a heck of a fuel leak the other day, I don't know what clogged up but it had a stream of fuel shooting 6' from the filter cap, I'm sure the pressure blew out the rubber seal on the filter. I had a couple of minor leaks so I thought I'd go ahead and put a new seal kit in the fuel bowl. Every thing went pretty smooth until I messed with the FPR. I ended up having to buy the little screen assembly and check ball....lost the sucker, I think one of my dogs ate it but couldn't wait until they crapped it out. :-arrgh Anyway I pulled the FPR apart and cleaned it real good and put new seals in it and all that good stuff. I put everything together and the fuel bowl fills up but the truck won't start. I had my wife spin the engine over and I checked the Shrader valve and I have absolutely no pressure with the engine spinning like a top. It turns over fast enough to build oil pressure but it will not start, not even a cough....Any ideas..right now it's my only mode of transportation so I need to get it back on the road quick. Any help will be greatly appreciated. Oh yea it's a 97 F-250 7.3 L bone stock.

ReBilld 08-05-2014 09:33 PM

Just a thought, but it sounds like it could possibly be a bad fuel pump.

desertdogs 08-05-2014 11:21 PM

The fuel pump seems to be working fine, it's filled up the filter canister. I don't quite know how the FPR works, such as where exactly does it draw the fuel from. There are three fuel lines connected to it, the one towards the firewall from what I understand is a return line and the two forward ones feed the injectors if I'm not mistaken. I haven't been able to find a decent book on it so I'm pretty much guessing at this point. If the fuel pump wasn't working would it fill the filter canister? I don't know I'm sort of at a dead end on this.

ReBilld 08-06-2014 04:34 AM

The fuel pump is a two stage pump. One stage fills the fuel bowl and the other stage pumps high pressure fuel to the injectors through the steel lines off the back of the pump that go into the back of the heads. The two hoses that come off the front of the heads are return lines. These are regulated return systems.

Awitte58 08-06-2014 08:36 AM

Bill sounds like he might be right.

Does the Tachometer move while cranking?

Hussler 08-06-2014 08:53 AM

This thread has a diagram that may help you understand the fuel system ...

https://www.ford-trucks.com/forums/8...ont-start.html

desertdogs 08-06-2014 09:16 AM

Ok, now it's making more sense to me. I didn't realize it was a two stage pump, I thought the FPR delivered the fuel to the injectors. I guess the next step will be to replace the fuel pump. I do have a question on the FPR though, the screen assembly with the ball in it, does it stick out from the FPR housing or is it supposed to fit flush in the housing. Mine sticks out about 3/8" which by looking at it looks correct as the ball takes up the space below it. I've just never worked on the injection system other than replacing glow plugs two years ago.
Also when I developed the huge leak it was running, I had to drive 25 or more miles with that sucker peeing out fuel. In that 25 miles I figure I must have gotten about 2-3 miles a gallon..I literally watched the fuel gauge go down, it was like flushing a toilet.
Any advice on getting that mother out of there with out screwing something else up?
Also "Alex" yes the tach moves when it's turning over...I'd estimate 250 rpm's, the batteries are fairly new having replaced them last fall.
One bit of info....I bought a fuel filter at AutoZ one and they have a new kind of seal they put on them. No.1 the cap doesn't seem to fit right and the O'ring or seal doesn't seat right....wouldn't recommend it to anyone. I don't know if you can pass that info on or not. I figured I was going to have problems with it after reassembling the sucker...so I bought one from a different store and sure as heck it leaked like a sieve...so much for a clean valley.
Any more tips would greatly be appreciated.


farmert 08-06-2014 10:15 AM


Originally Posted by desertdogs (Post 14562058)
Ok, now it's making more sense to me. I didn't realize it was a two stage pump, I thought the FPR delivered the fuel to the injectors. I guess the next step will be to replace the fuel pump. I do have a question on the FPR though, the screen assembly with the ball in it, does it stick out from the FPR housing or is it supposed to fit flush in the housing. Mine sticks out about 3/8" which by looking at it looks correct as the ball takes up the space below it. I've just never worked on the injection system other than replacing glow plugs two years ago.
Also when I developed the huge leak it was running, I had to drive 25 or more miles with that sucker peeing out fuel. In that 25 miles I figure I must have gotten about 2-3 miles a gallon..I literally watched the fuel gauge go down, it was like flushing a toilet.
Any advice on getting that mother out of there with out screwing something else up?
Also "Alex" yes the tach moves when it's turning over...I'd estimate 250 rpm's, the batteries are fairly new having replaced them last fall.
One bit of info....I bought a fuel filter at AutoZ one and they have a new kind of seal they put on them. No.1 the cap doesn't seem to fit right and the O'ring or seal doesn't seat right....wouldn't recommend it to anyone. I don't know if you can pass that info on or not. I figured I was going to have problems with it after reassembling the sucker...so I bought one from a different store and sure as heck it leaked like a sieve...so much for a clean valley.
Any more tips would greatly be appreciated.

On the fuel filter, did they give you the correct filter for the OBS truck, and not one for the Superduty? I seem to recall a thread that the superduty filter will not built fuel pressure if used in our trucks, or something to that effect.

desertdogs 08-06-2014 12:25 PM

@ Jim, thanks for the diagram on the fuel system. It's making more sense to me now as to how it all works. I ordered a new fuel pump and as soon as it gets here it's back to living under the hood for a while.
@ Tom, I'm not sure if they gave me the wrong filter or not...it didn't fit right though and when I had my wife crank the engine over it spit fuel all over the place. I replaced it immediately because I suspected something was wrong with it and picked up a different one when I went to town.
I still have the question of the screen and ball assembly on the FPR...does it fit flush with the FPR body or is it supposed to stick out approx 3/8 to 1/2" and fit into the filter body?
I ordered a new fuel pump which I should have replaced when I had it all apart. At least I've taken it apart enough times I can pull all that stuff in an hour or less. Might as well remove it all and clean the valley of death out again since it filled with fuel from the filter housing leaking. That pump doesn't look like it'll be a whole lot of fun to replace though.

fordpride 08-06-2014 12:30 PM

http://www.dieselorings.com/docs/OBSFuelBowlRebuild.pdf

desertdogs 08-06-2014 05:12 PM

Thanks Mike, that is very informative link. I now know exactly how everything is sitting in the proper places. Luckily, I did do it right just by guess work for the most part. Now all I have to do is replace the fuel pump and I should be good to go. That sure doesn't look to be a pleasant job by any means especially for someone who's got a bad back. I've been leaning over that truck for a couple of days now and am paying for it but that's life. :-blah

Anyway thanks again, this is the best forum I've ever been on. Every time I've needed help every one steps up to the plate. :-drink


All times are GMT -5. The time now is 01:03 AM.


© 2024 MH Sub I, LLC dba Internet Brands