A question for Injection Pump rebuilders and experts.

[danda]

Calling for help from those of you that have rebuilt one of these IPs!

I need info about the IP outlet "Fuel Return Regulator Housing Pressure Fitting".

Ok, so some call it a "check valve" but apparently it is supposed to regulate IP fuel pressure somehow. Anyway, I'm referring to the IP outlet that a hose barb threads into which the return line hose attaches to.

Here is a picture.

Ok, so I took mine off to check the o-ring. I could look through the thing and see daylight. I did not see any ball or spring. I also did not try pushing on the end of it, because at the time I didn't realize that is a way to test them.

But yeah, I've read that there is supposed to be a ball and spring in there. I tried watching some db2 rebuild vids on youtube and a couple of them talk about that valve a little bit, but so far none of them actually take the thing out and test it or give an details.

I am suspicious that I can see light through mine and I don't see any ball. So my first question would be: is that normal?

Second: if that is not normal and mine is (somehow) missing parts, how would you expect that to affect engine operation? As far as I can tell, the engine is running normally both before I removed it and after re-installing. I have had the ongoing hard start situation, but I believe that will be resolved now that I found a leak in return lines and have re-routed them (today).

Third: where could that ball (and spring?) have gone? Only thing I can think is that someone (not me) took it apart before and lost them. But if so, it was before 2001 when I bought the truck, and it was running just fine for years after.

 

[danda]

also, does anyone have a Ford or GM or Stanadyne part number for it? I'm having trouble finding other sellers.

 

[Jesus Freak]

I'm all about rebuilding the IP, but it appears to be "top secret" "hush, hush" territory. Good luck with your endeavors and please post your progress as there's a couple of us on here that are just as willing to dive into this uncharted, shark infested water as you. I wish I had more information for you.

 

[Kdo58]

Pretty sure the ball is clear, like a piece of glass, i cant remember but it seam like you should be able to shake it and hear it rattle

 

[danda]

I didn't think to shake it. Doesn't it strike you as odd though that I could see right through the valve? I would think the ball should be in the center...

 

[danda]

I'm all about rebuilding the IP

In case it wasn't clear, this is the outlet threaded into the top of governor housing. It can easily be removed with the pump fully mounted just by removing the outlet hose. So anyone can inspect it, not only pump rebuilders. I just figured they would work with it regularly.

 

[Kdo58]

Pull it off you should be able to only blow through one direction.

 

[IDIBRONCO]

The only rebuilder who gets on here fairly regularly anymore is Russ. If he doesn't reply to this thread in a few days, you may try sending him a PM.

 

[danda]

I found this comment:

There is one additional function of the check-ball "housing pressure regulator valve." It only applies to farm tractors with fuel tanks lower then the engine and the valve mounted at the exit of the pump. It's to prevent fuel drain-back and difficult cold starting. It was a big issue on Ford and GM cars and trucks late 70s and early 80s with DB2 pumps.

So if mine is missing the ball (as it seems) then this could be a contributor to my hard start issues after sitting.

 

[danda]

Ok, I have some pics.

1. Location. Top of the IP. Underneath the barbed hose fitting, which threads into the check valve.

You must be registered for see images attach

2. The check valve, removed. Notice the front nozzle appears empty (no glass ball).

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3. I can see light through it. No spring, no ball.

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From reading a few threads about it, I gather people sometimes remove the glass ball if there is concern it may be sticking and causing engine shutdown when return fuel can't flow.

So I guess I will order up a replacement.

 

[ttman4]

I suggest wait till Russ @typ4 maybe sees this & responds.
I have a retired mechanic friend that told me years ago to take that valve off & gut that ball out. I can't recall now why he suggested doing it. He worked thru the '80s & '90s at Chev Dealership here in Or & worked on lots of DB2 pumps rebuilding etc etc.
I try to call him tomorrow & ask.
As far as rebuilding IPs I leave it up to folks like Russ!!!! Back back in early & thru '90s there used be place on Regal Row in Dallas,Tx that I used when back down there that rebuild IPs & injectors. They used let me go into & watch in their "Clean Room" that had about a $gizillion dollars of equipment to rebuild everything with. I decided to leave IP rebuilding up to professionals!!!!!

 

[Black dawg]

Did you try putting air through it?

 

[danda]

yeah I blew some air through it just to clean it out. blows either way no prob, as one would expect for an empty tube.

 

[danda]

I have a retired mechanic friend that told me years ago to take that valve off & gut that ball out.

Yeah I'm hoping to hear from people with more experience.

From what I've gathered googling around....

On the one hand, removing it eliminates a possible source of failure that can lead to stalled engine.

On the other, apparently it also drops internal pressure by 4-6 PSI, which can actually affect the timing.

Also, it might cause return-line drainback issues on some installations.

 

[Black dawg]

Its function is to regulate housing pressure, it does act a check valve, dont know if it is needed as one though.
Without the valve regulating housing pressure, timing will be advanced everywhere. In my experience, pumps tend to act a little weird without the valve creating housing pressure.
Very easy to check function with an air gun.