Injection Pump Won't Prime

[fixt]

Massey model 65 Diesel Perkins AD4.203

I had the thing running fine after changing both fuel filters a bout 3-4 days ago, went thru the venting procedure in the book and it all worked great.

Now, I have a no start condition.
I can't get the injection pump to prime. I have no bubbles at either filter and no air bubbles at either pump vent. I have 3 of the pump injector lines loose and I get no fuel.

Is it possible my fuel pump is FUBAR? When I try to pump it, I get a very short priming stroke, Not even a 1/4". I have rolled the engine to get it off the cam but I still get a short stroke. It strokes less and less, I can't get 10 full strokes of the pump.

Help me out here?

 

[fixt]

I just went and tried the lift pump again.
I got three full strokes then progressively less and less.
I don't get it. The lift pump acts like it is starving for fuel, like a vacuum is being formed or something.

 

[Dieseltech]

Don't blame the injection pump yet, there are some simple things to check first. I get pumps in for repair sometimes that other problems are the cause. First is the filters, are they NAPA/WIX brand, installed CORRECTLY? The filter top outer groove is the fuel inlet, it must be open. Common mistake guys make is to put an extra O ring in there, blocking or shutting off fuel flow completely. Next is the final filter top banjo bleed orifice fitting, when it's plugged the trapped filter top air can't get out to the return as it should and goes to the injection pump inlet, causing shut down. The orifice is on the side of the bolt, .020 inch size. Make sure it's open. Supply pump MAY also not stroke by the hand lever IF the engine lever is held up by the cam inside, bump the crank one turn with the starter will get the hand lever to work..

 

[fixt]

Thanks for the reply Dieseltech.

Yes, they are NAPA 3166, 2 of them. The writing on them is oriented up just like your picture.
The filters came with O rings and I made sure to get the old ones out from the top groove in the filter mounting and then installed the new ones. No leaks.

For the banjo fitting on top of the secondary filter I'll have to check that bolt.

I've bumped the engine several times in an attempt to get a full stroke on the lift pump,trying to find the sweet spot.
BUT I only get a full stroke a couple times after it has sat for 10-15 minutes.

I just went and tried again after sitting for about 20 minutes.
I got 4 full strokes and then less and less. I also rolled the engine with the injector lines loose, no fuel.

Ima go check the banjo bolt now.

 

[fixt]

I just removed and checked the banjo bolt. I sprayed out the little hole (man that thing is tiny) and I got bubbles in the center with brake fluid cleaner. So I'm satisfied its not blocked now. I do not know if it was before or not. I was going to run a pin drill through it but I've misplaced mine, I only found the pin vise set.

I'll go back through the entire vent procedure now and try it again.

The lift pump still won't go 10 strokes though. It becomes less and less after about 4-5 strokes until I get nothing.

 

[ptfarmer]

A common problems with the NAPA WIX filters, this happens a lot with those filters.

 

[fixt]

I didn't put the O rings in the filter.
I put the O rings in the groove at the top of filter that the filter lip sets in.
I don't think they rolled out, they're flat and I don't have any leaks from the filters.

 

[Dieseltech]

The hand lever WILL feel like it's going out of stroke on a good working feed pump. Wait a bit and it will change again. Most important bleed screw on the injection pump is the lower one next to the name tag. It MUST be air free or injection pump will never work. Top cover bleed screw can be done after engine is running. Also note, with the engine running and top bleed screw loose there MUST be fuel come out. If not feed pump is not working correctly, system is designed to supply more fuel than needed for lubrication and cooling. No fuel while running at the top screw means something is restricted, or not enough flow in the first place.

 

[fixt]

The lift pump does feel like its out of steam after 4-5 pumps and if I wait about 15 minutes, I can get 4-5 more good strokes.

I got a good stream (no bubbles) out of the bottom pump screw but then nothing out of the injector lines when I rolled it.
I'll let it sit a while and try it again.

Its on the battery charger right now.

 

[Dieseltech]

If you have good air free fuel at the lower bleed screw then injection pump MAY be the problem. Remove the stop cable at the front lever, set hand throttle at 1/2 or more. Now SLOWLY move the stop lever back and forth, you should feel the metering valve stop bar contact the valve turning the lever Clockwise just about half way. NO change at all means the valve is stuck in the fuel off position. With the stop lever fully Counter Clockwise in fuel on position valve MIGHT free up by tapping the hydraulic head near the outlet lines. If the valve is not stuck, and you can feel it with the stop lever it's not stuck. Then it could be stuck rotor plungers, or worse a seized head assembly.

 

[ptfarmer]

 

[fixt]

I'll try that in the morning when it warms up a bit iffen it don't rain.
Would the pump just suddenly die in its sleep like that with out exhibiting any symptoms?

Like I said before, it was running fine after the filter change then all of a sudden, nothing.

 

[ptfarmer]

Here is a good video explaining how the injector pump works.
https://www.youtube.com/watch?v=kqDBMLB7jcY

 

[Dieseltech]

If the rotor seized in the head, yes, it will die all of a sudden. When that happens the head needs pressed apart to find the seizure area, and determine the cause so it can be corrected..

 

[MKinON]

Any chance it could be a blockage to the lift pump? If so, wouldn't that cause similar symptoms at the IP? Just wondering.

 

[ptfarmer]

(quoted from post at 21:58:39 03/09/18) Any chance it could be a blockage to the lift pump? If so, wouldn't that cause similar symptoms at the IP? Just wondering.

It's possible, the fuel shutoff valve usually has a screen that could be blocked enough to where it can get some fuel, but not enough for it to bleed, or run.

 

[fixt]

OK, I am fairly confident I found the problem.
The red line points to the throttle linkage which has two flat sides to it where it bolts to the injector pump.
It had slipped off the flat sides and was doing nothing. I don't remember what I did to it if anything, but I was in the area replacing the manifold.
So I started checking everywhere I'd maybe fingered something. That usually puts me on the right track to where I screwed something up. Check check and doublecheck.

I could not feel the stop lever contacting the valve at first (circled spring removed), then I corrected the linkage problem and now I can feel it contacting the valve with the throttle set at half.

The spring on the stop lever is there because there is no spring on the rod itself (as pictured in the parts book) to return the stop lever to the run position. Maybe I can make one out of some plumbers tape and screen door spring(LOL).
Actually something similar to the regular diesel agricultural model rod spring return.

The three injector lines are what I have loose to bleed the air, I only opened 2 of them before and was all I needed.

Rain has run me in and when it quits after while I'll give it a go and see what happens. I think I'm fixed now, we'll see.

 

[Dieseltech]

That would do it if the lever is not on the shaft flats correctly. Not common for those to come loose, but I do see it on occasion..

 

[fixt]

ALLRIGHTY!
That was it. It must have been almost off before, because I had to set idle speed. It was way down around 300 rpm or so by the tractormeter so I set it to 450-500 rpm. High speed wouldn't go any more than 1500 rpm so I set it up to 1850-1900, locked the nut, and reinstalled the little cover sleeve.

I'm gonna pick up some nylock nuts to try and get on there in place of that little brass nut

Oh, I had a good stream coming out of the upper injection pump vent with it running, so I'm calling that good.

Thank you so much for your help.

That video posted by ptfarmer about how the injection pumps work was very enlightening. I wouldn't be so scared of gutting one now (as long as I had a spare and a way to test it). No way, I'm still scared of them. Not something to be undertaken lightly.

 

[Dieseltech]

It should NOT have brass nuts on it anywhere. Low idle is best at 700-800, Hi idle no load stop screw should be 2160-2200. E-mail me your address and I'll send you the correct lever nuts..

 

[fixt]

Thank you again.
I thought the nuts looked like #10 fine thread but it may be proprietary threads.
I sent you my address, I'll reset the rpm when I replace the nuts.

 

[Dieseltech]

I got the E-mail, will get some to you in the mail Monday. I sent you an E-mail, but it didn't go through for some reason. Been having trouble responding..

 

[Bob in Australia]

I have a 1963 MF 65. They are terrible to prime, but a few things I have found. 1) try to get a bit of air pressure in the fuel tank. I made up a cap with air valve
in it. Need to be careful only to add a bit of pressure but it does wonders, if you then follow the standard bleeding procedure. 2) tap the engine over with the
starter until you get good movement in the hand primer. 3) if all else fails, replace the primary fuel pump with an electric pump, then go through the
standard bleeding procedure. They simply will not start if there is air in the system.