67 3020 DBGFC431 Pump issues

[Crracer712]

Hoping to get some advice or input.

Got the 67 3020 with the Roosa Master DBGFC431-3AJ IP. Getting fuel to the pump, but not to the injectors (cracking the fuel rail fittings near injectors).

Tractor sat for a couple years, used to run fine, no it won't start due to no fuel.

I've emptied and refilled the fuel tank full with fresh fuel, changed the fuel filter. Transfer pump pumps fuel as well as does the primer on the transfer pump, up to the IP.

From all the research I've done, It appears possibly stuck plungers. I've had the 3 screw cover off and it appears the metering valve is free and operational. Relatively clean inside with a light coat of rusting looking sediment on the bottom(pump stands vertically).

I'm pretty mechanically inclined, have the manual, watched tear down and repair videos several times. I'm psyching myself out to pull to the pump and pull it apart to see if the plungers are indeed stuck.

I've pulled the timing window cover off, no debris, only clean fuel, so I don't know about that weight basket rubber being deteriorated. I also have no idea about how long ago or even if the pump has ever been serviced. I've owned it since about 1998, has ~1200 hours on the engine, I've only put about ~250 of those hours on it since I bought it.

Regarding the return fuel line, since the pump sits vertically, there is an elbow coming out of the 3 screw cover plate which the return line attaches too. I was under the impression there should be a check valve at that location, but I pulled that cover off last night to check the metering valve operation and I pulled that elbow out, it appears to be just a regular elbow, same ID at both end, can blow through it either way. Do I need the check valve here, and why wouldn't it have one, what trouble would it cause removing it?

Any advice appreciated, and thank you

Rod

 

[thepumpguysc]

The 3AJ does NOT carry a checkball fitting.
"IF" your going to attempt a teardown, get a gasket kit first.. 24371
That way u can replace the orings as u go.. good luck.
I'll send u a prvt msg.

 

[Crracer712]

Good to know on check ball for return line. I'm guessing this is a pretty early DB pump then? Did they add the check ball later to assist in quicker starting?

I did stop up to iola turbo and diesel and picked up a stanadyne seal kit, just in case, along with a new screen for the inlet regulatory valve(original looked pretty clean but did have that faint rusty looking residue).

 

[thepumpguysc]

Yeah, itsa VERY early unit..
I know this guy in SC that has some time on his hands & would be willing to give u a hand.. lol
That pump superseded to a 16AJ.. if u have a TRUE 3AJ it will have JUST a screen on/under the inlet.. & the pressure regulator on the side of the endplate.
If u have a 16AJ it will have a screen ON the pressure regulator{removable} under the inlet..
When they sold u the screen, does it have THREADS on it.?? or is it just a wire screen..{hollow}

 

[Crracer712]

With TPG's, I'm finding my 3AJ pump has a few updates, not all. Kind of a mix of stuff. Pumps tore apart, cleaned(stuck plungers, and advance timing was seized on one side.).

Gotta pick up the collar bushing for the drift shaft tomorrow and hopefully get it reassembled.

Big thanks to ThePumpGuysc!!

 

[thepumpguysc]

U HAFTA let the glue dry that u put on the pilot tube..
It doesn't have a "stop" so measure the protrusion.. before pressing the old one out..
THE OLD ONE might be glued in.?? It'll take a lot of heat to let the old one go..
I use a MAP gas bottle. {yellow}
The standard BLUE bottle never worked for me..