Fuel- High pressure relief valve

[JMBT]

Well it looks as if I may be replacing my high pressure relief valve on the road this weekend. Quick serve directions don’t look bad, except the pulling of the seal with a modified Allen wrench and swedging the new one back in! What the hell! I’ll tell ya, BIG RED could f@&k up a wet dream with all this ridiculous shi#t!

Anyhow,.... who has replaced their high pressure relief valve? Any tips or tricks? How bad was the seal to pull and replace? Did you use a modified Allen or something else?

Thanks in advance.

[snailexpress]

(12-16-2017 )JMBT Wrote:  Well it looks as if I may be replacing my high pressure relief valve on the road this weekend. Quick serve directions don’t look bad, except the pulling of the seal with a modified Allen wrench and swedging the new one back in! What the hell! I’ll tell ya, BIG RED could f@&k up a wet dream with all this ridiculous shi#t!

Anyhow,.... who has replaced their high pressure relief valve? Any tips or tricks? How bad was the seal to pull and replace? Did you use a modified Allen or something else?

Thanks in advance.

How do you know the valve is bad. What if fuel actuator doesn't regulate proper fuel supply and pump create too much pressure.
Don't worry about seal washer it's easy.

[JMBT]

I had code 3727, last night with code 1911. The tree for 1911 says troubleshoot 3727 first. 3727 is pretty cut and dry to replace the valve. Then troubleshoot 1911. 1911 then has you check the actuator, sensor,...etc.
Curiously though, as you read on down into the “shop talk” section, you find 1911 can be set by a whole bunch of crap not even related to the fuel system. Like low voltage from the alternator, or a bad ECM ground. (Good job Cummins)

I just figured I would start with the valve as per code 3727. Also, and I know this isn’t necessarily correct thinking, but the actuator was new on the brand new fuel pump I recently put on. (Not a reman) and the valve has 640K on it, so I want to believe it is the valve. Did you grind down an Allen, or use something else for the seal. How about putting the new one in?? Remember I will be at a truck stop and have limited tools.

[snailexpress]

Don't remember what exactly was used. 100% not allen wrench.
Where is truck stop located do we have chance see show:big_smile2::big_smile2::big_smile2:

[JMBT]

Haven’t picked the truck stop yet, but I’ll keep ya posted!!! Seems to be behaving now. I ran through the night and all day, easy on her, with no more codes. I have to pick up Mon morning and will deliver Tues. I’ll Be 90K gross, but thinking if it behaves I’ll baby it until I deliver, then head for my brother’s in OK.

[Starlight]

I'd try getting that relief valve diagnosed properly. In northern Canada a 390 dollar part is steep to just see if it'll fix the problem. A leaking injector or high return flow from the pump head could trigger that code depending how sensitive the pressure sensor is on your particular engine. Just because the pump is new like you said is no guarantee it hasn't started to leak even though it's unlikely.

[JMBT]

I guess I don’t know how else you would diagnose the relief valve?? Cummins fault tree for 3727 just says replace it. Code 3727 says the relief valve has tripped at too low of a pressure, not too high. Cummins apparently interperets that as, it is faulty, and must be replaced, (or can’t be trusted). I guess it could be just Cummins CYA, but I am open to other suggestions if you have some.
I agree the pump could be leaking even though it is new. Many new parts these days are crap. And from my experience the 2 cylinder pump “upgrade” is junk compared to the old three cylinder. They should have just made an update kit for the old three cylinder, but....that wouldn’t make mother Cummins $4600 a pop. I really think there could/should be a class action lawsuit associated with all the engineering F-ups on the 2250’s and 2350’s.
That being said, I don’t think high return flow or a leaking injector would set code 3727.

[Starlight]

Don't know the tooling part number but basically says if you have 10 or more drops leak from it with the fuel leakage test running then it fails.

[JMBT]

Thank you for the info, they also say to replace it if it throws 3727...