Fuel pump check valve

[Mike_H]

I started to diagnose why my Jeep is so hard to start today. I've always suspected the anti drain back valve, but before I drop nearly 200 bucks on a new assembly, I wanted to be sure.

Oh... Curse Jeep for removing the Schrader valve from the fuel rail. Cost me an extra 30 bucks to build an adapter to get my pressure gauge installed!

Pretty sure this is the confirmation I was looking for...



Going to order the Bosch replacement from Amazon. Good thing I've got so much practice dropping the tank!

 

[KCsTJ]

I started to diagnose why my Jeep is so hard to start today. I've always suspected the anti drain back valve, but before I drop nearly 200 bucks on a new assembly, I wanted to be sure.

Oh... Curse Jeep for removing the Schrader valve from the fuel rail. Cost me an extra 30 bucks to build an adapter to get my pressure gauge installed!

Pretty sure this is the confirmation I was looking for...



Going to order the Bosch replacement from Amazon. Good thing I've got so much practice dropping the tank!

Yes why did they leave The Schrader valve off, that's stupid!
Very nice pressure test rig up! May I copy that since they didn't put one on my jeep either :-/

 

[Mike_H]

Yes why did they leave The Schrader valve off, that's stupid!
Very nice pressure test rig up! May I copy that since they didn't put one on my jeep either :-/

Sure thing...3 feet of fuel line, and a couple fittings. The steel fuel line is 5/16. I bought some of those dorman pieces to put it together. The gage is in a kit from harbor freight I picked up for 20 bucks. I can take some pics tomorrow.

 

[Mike_H]

@KCsTJ

My promised How-To, complete with Part numbers!

https://wranglertjforum.com/threads/how-to-check-fuel-pressure-on-a-03-and-later-4-0l.11793/

 

[KCsTJ]

@KCsTJ

My promised How-To, complete with Part numbers!

https://wranglertjforum.com/threads/how-to-check-fuel-pressure-on-a-03-and-later-4-0l.11793/

Thank you @Ranger_b0b, thats a really slick way to check fuel pressure if no Schrader valve.
I'm going to add this to my collection of diagnosing tools . This is a quick way to rule out or dx fuel pressure problems

 

[pjmcg]

If you don't want to drop the tank and buy and new fuel pump assembly, I just added a check valve and it worked great.

 

[Sahara_Green_4.0]

If you don't want to drop the tank and buy and new fuel pump assembly, I just added a check valve and it worked great.

I saw your video and I thought this could be a temporary fix for my problem(jeep takes like three times to start). I already ordered all parts but yesterday I read that this method can cause leaks on other parts of the lines because it can increase pressure. Did you had some problem days after installed?

 

[pjmcg]

I saw your video and I thought this could be a temporary fix for my problem(jeep takes like three times to start). I already ordered all parts but yesterday I read that this method can cause leaks on other parts of the lines because it can increase pressure. Did you had some problem days after installed?

If you had installed the check valve the wrong direction I could see how it could overpressure the line between the pump and the check valve. Other than that I'm not sure how it would increase pressure unless the check valve is bad. In that case, the engine wouldn't start. The whole idea is to keep line pressure between the check valve and the fuel rail.

 

[macleanflood]

Imho I could drop the tank and replace the pump assembly faster than y'all can write more posts on how to bodge something together that's not hard to just do it right anyways.

My ten cents...

-Mac

 

[pjmcg]

I said, and I quote... "If you don't want to drop the tank and buy and new fuel pump assembly..."

I couldn't resist... so does that include removing rusted bolts, re-welding captive nuts, disconnecting hard to reach never-disconnected-in-20-years connectors?

Respectfully, it's not an "easy" job.

 

[macleanflood]

re-welding captive nuts

All fair points but technically the bolts are carriage bolts...no captive nuts. I did replace a lot of mine with stainless nutserts to make it easier.

-Mac

 

[pjmcg]

All fair points but technically the bolts are carriage bolts...no captive nuts. I did replace a lot of mine with stainless nutserts to make it easier.

-Mac

There are bolts along the rear of the tank that were rusted - about half of the 6 or so? Had to cut them off. Those might be the carriage bolts you mentioned.

What I was referring to was what I'd call a captive nut where one of the tank straps (passenger side?) bolts to the underside of the body. That was destroyed removing the rusted bolt, so had to re-weld in a new nut.

 

[macleanflood]

Rusted bolts and stuck connectors are a major PIA.

I believe the tank straps to the skid and the skid bolts to the frame via carriage bolts. Quibbling.

-Mac

 

[TJ4Jim]

If you had installed the check valve the wrong direction I could see how it could overpressure the line between the pump and the check valve. Other than that I'm not sure how it would increase pressure unless the check valve is bad. In that case, the engine wouldn't start. The whole idea is to keep line pressure between the check valve and the fuel rail.

Since the fuel pump is capable of producing higher pressures that are controlled by the regulator an in-line check valve is capable of trapping that pressure if the regulator fails preventing the pressure bleed off.

 

[Sahara_Green_4.0]

Imho I could drop the tank and replace the pump assembly faster than y'all can write more posts on how to bodge something together that's not hard to just do it right anyways.

My ten cents...

-Mac

I don't doubt it man... I changed the pump once and the problem was solved. But only lasted like three months. I was looking for a more easy solution and not wasting more money not knowing if this time it will last.

 

[macleanflood]

I don't doubt it man... I changed the pump once and the problem was solved. But only lasted like three months. I was looking for a more easy solution and not wasting more money not knowing if this time it will last.

Try a Brute Power off Rock Auto.

I've abused mine and it's running great two years in.

-Mac

 

[Sahara_Green_4.0]

Try a Brute Power off Rock Auto.

I've abused mine and it's running great two years in.

-Mac

Thank you. They are out stock since my jeep is a 2000. It looks like part number is 1010095. Found it in Amazon for $104.80