DB2 Leaking

[AWOL]

I noticed over the weekend that I started leaking fuel. After awhile of searching I see that it is coming from a weep hole on the bottom of the pump at the very front of the engine... Can anyone tell me if this would simply be a seal or gasket? Does anyone have a copy of the service manual for these? Or a exploded/parts layout or anything? Talk about hard to find! I do have a second pump from a J code 6.2. Any reason I couldn't use it? Thanks!

[chevytuff]

I could be wrong but I am not aware of a weep hole on the bottom of the DB2 pumps and have several laying around in the shop, There is an inspection plate on the side of the pump that could be leaking. Do you have any pictures of the leak. it may help clarify what you are talking about.

[AWOL]

I'll get a picture of it tomorrow. After searching for awhile I believe it is a vent hole. If you flip the pump upside down there is a small hole up close to the face of the pump where the studs come through to mount the pump. I was able to see it using a fiber-optic flex-cam. When the motor is running I could see fuel weeping out.

[DmaxMaverick]

If fuel is leaking from the weep hole (vent, or whatever you want to call it), the pump shaft seal has failed. Only an overhaul (or new/reman pump) will fix it. The hole is there to prevent fuel from leaking into the crankcase, should the shaft seal fail, as you can see.

[AWOL]

That was what I thought... Well I guess it's time to pull a pump apart! Should be fun! Any reason the other pump I have wouldn't work? It's from a J code 6.2L.

[DmaxMaverick]

You can take the pump to a Stanadyne service shop and have them test it. If the pump is otherwise solid, they can replace only the seal. They will (and should) suggest a "refresh" of other pump internals. MUCH cheaper than a complete overhaul of a worn out pump (much fewer hard parts that get trashed when a pump goes south). If you don't have previous Stanadyne pump internal experience, the complete manual, and a Stanadyne calibration test bench, it's better left to the pros. Most are very reasonable and helpful.

All DB2 pumps are interchangeable (the only exception is the 12V/24V versions, which are easily converted one way or the other). Later pumps are more reliable/durable, but all are plug and play. The only variable is the fuel rate adjustment between models/series.

[AWOL]

Thanks! I have a complete manual on the rebuild of the pump and some experience. The local shop out by me isn't very friendly to deal with so I am thinking about trying it myself. I can always bite the bullet if need be and walk in submitting to the ego of there shop after. The other pump I have is a 24v. but I imagine a can convert it with the parts I have on my non working pump?

[DmaxMaverick]

The ESS and HCPA solenoid will swap over. Most conversions don't include the HPCA, as the 24V solenoid will normally work fine at 12V.

Proceed at your own risk. Still, I recommend a bench test and calibration after you finish. The risk is a runaway engine you can't stop. Have an alternate engine-stop method in place before you crank it, such as a method to manually stop the fuel or air flow.

[AWOL]

Well...I got the other pump switched over and installed. Everything works great! The truck actually runs a lot smoother and feels like it has a little more pep. Thanks for all your help! Over the winter I want to rebuild the spare motor I have (A J code military take out) and start fixing the little bit of rust the truck has before it gets beyond the surface.