Engine/Transmission (1994 - 1998) leaking DV... add washer?

[Forrest Nearing]

my #1 delivery valve is leaking... again... can I add a thin copper washer/gasket to help seal it or is that going to effect the fuel delivery balance between cylinders? (IE, would I have to add washers to all six valves)



any tips on getting this thing to seal properly? originally it was leaking because the guy I bought the truck from bent the #1 injector line out of the way when setting timing which caused a couple small paint flakes to fall on the seating surface... I pulled everything out and picked the paint out... everything seemed fine for a while, but it's leaking again.



TIA,



Forrest

 

[drrhoades]

Did you replace the o-ring under the DV nut, or whatever you want to call it. They forgot to replace mine when I had my timing done and the thing leaked like crazy.



Doug

 

[Forrest Nearing]

it is my impression that the only thing sealing the DV is a metal-to-metal seal... some engines had copper washers from the factory, others did not. mine does not. I believe the only soft o-ring in that area is just to keep crud from falling down in there, it's not sealing fuel.



Forrest

 

[drrhoades]

On mine the original o-ring was cut alittle when they were putting it back together and it was leaking fuel pretty bad. the new one cured the problem right up. it is a green o-ring.

 

[HoleshotHolset]

The fine folks at PDR mentioned to me that sometimes you have to 'lap' the DV holder and the top of the DV valve itself so that they're nice and flat to make a good seal.



I used some really fine grit sandpaper... a piece of glass (for a good flat surface to put the sandpaper on... )... and some air tool oil.



Do some figure-8's with the DV holder and the 'seat' part of the DV... .



I had a few leakers... . lapped all my DV's and replaced all the o-rings and I was good to go.



The paint on the P-7100 in the DV area will help to rip the o-rings when you take them out... . I got rid of all the paint and from now on won't re-use the o-rings.



I had to get my o-rings from PDR as the local Bosch shops weren't cooperating with me at all.



Matt

 

[nascar mark]

Matt is right on with this one. Thanks Matt

 

[mikel]

I had a DV leak after the timing was set, paint flakes got in there. I replaced the metal washer and the o-ring after fishing out all the paint flakes and no more leaks.



Mike

 

[Forrest Nearing]

Mike,



my question is can I add a washer where there wasn't one originally? my '97 doesn't have washers, but I think the copper would help to seal it up.



Forrest

 

[HoleshotHolset]

Forrest: Try lapping your DV's... you might be surprised at how well it works.



I'm not so sure I'd put a copper washer in there if I were you... especially since it didn't have one in there to begin with.



The reason your DV is leaking is most likely related to a poor mating surface between the DV holder and the 'seat' part of the DV itself.



Matt

 

[Forrest Nearing]

will just lapping the DV holder work? I'm scared to get down in the pump and do anything...



I figured the lack of copper gaskets was a bean-counter move since they weren't absolutely necessary to seal freshly lapped surfaces... seems like even the thinnest little sheet of copper down there would sure help fill in any non-uniformity (sp? word?!?) in the surfaces.



Forrest

 

[HoleshotHolset]

Forrest:



Not to worry about getting too deep into the pump... it's easy and really painless. Don't worry about messing up... just make sure everything's clean and don't rush it... .



Take out the DV holder (be careful not to loose the guts... )...

Take out the DV 'needle / seat'...

Lap the 'seat' part of the DV assembly...

Lap the DV holder where it seals against the 'seat'...



Sew it all back together and test for leaks...



Matt

 

[Forrest Nearing]

I've already been in there once getting paint flakes out, it's just kinda tight in there...



I'm just having trouble envisioning exactly how I'm going to properly lap the seat surface in the pump.



Forrest

 

[mikel]

I don't think that HoleshotHolset is telling you to lap anything *in* the pump, you are going to work on the part that screws into the pump. The piece with all the little ridges on it that unscrews, and the delivery valve itself.



On another note, are you absolutely certain that there wasn't a washer in there? It should be a little thin aluminum thing. Maybe take #2 loose and see if there's a washer in there, if it's missing from #1 then I'd be more surprised if it didn't leak than if it did.



Hope this helps,

Mike

 

[HoleshotHolset]

Mike, thanks for clarifying that for me.



Matt

 

[Forrest Nearing]

well, now I have no idea what you're talking about... when I had it apart last time, there were paint flakes down in the pump on what appeared to me to be the seat that the DV holder sealed against...



I don't see how the DV itself could cause fuel to leak to the outside. just the seal at the base of the DV holder.



some pumps have washers, some don't. mine doesn't.



Forrest

 

[mikel]

Originally posted by Forrest Nearing

well, now I have no idea what you're talking about... when I had it apart last time, there were paint flakes down in the pump on what appeared to me to be the seat that the DV holder sealed against...

Sorry for the confusion, I was not aware that some came without the sealing washers. I learn something every day.



You are correct in your statement "on what appeared to me to be the seat that the DV holder sealed against". That is correct and you won't be "lapping" that if you decide to work on any of it.



If it were me I'd call someone that works on these pumps all the time and see if they recommend installing the washers to solve a problem with leaks. Maybe PDR, or someone local to you.



Let us know what you do to get it fixed, I'm real curious now.



Mike

 

[Forrest Nearing]

thanks, I figured a pro might see this post and reply to it! LOL!



I'll definately post up the results. I'm going to get some washers from Cummins and experament.



Forrest

 

[Cooker]

Originally posted by mikel

I don't think that HoleshotHolset is telling you to lap anything *in* the pump, you are going to work on the part that screws into the pump. The piece with all the little ridges on it that unscrews, and the delivery valve itself.

This is what I had to do to solve my leak. It was recommended to me by Piers.