3000 Diesel Fuel delivery problems

Hello. Working on a friends 3000. It is a three cyl Diesel with CAV injector pump. The tractor started running badly with white smoke / not pulling at summers end and it was parked. Over the fall, the exhaust stack was left off and small amount of water got in. We got it all dried out, changed oil, etc..., did not find any cracks and motor was not frozen. But, it would only barely idle after pull starting and still puffing lots of white smoke.

He had never serviced injectors so we replaced them and flushed and filled the unit with fresh diesel. Changed fuel filter, bled it, the pump, and we are getting fuel to the injectors. Then found the air filter had also got some water in the oil and the draft tube was clogged. Cleaned all this out and the tractor will now start but will not rev or hold an idle for more than about 5-10 seconds.

Weird part is that if you let it set a couple of minutes, it will start and idle normally and sound like it is ok (but will not rev up), then slowly idle down and die like it is running out of fuel again. You can repeat the wait, start, die process over an over, and if you hit the intake with start fluid it will keep running so we are pretty sure its a fuel delivery issue.

So what next? Could the tranfer pump on the CAV be bad? Should we just replace the injector pump? I don't have a way to do a compression test on this engine but it seems to start and run easily initially, just not for long.

BTW, we had a terrible time getting the old injectors out but then we purchased a 17lb slide hammer from a local cheap tool supplier, drilled out the screw end of the puller and fit the 5/16 24 bolt (that also fits the injector return hole), and used a grade-8 bolt in the puller. This pulled the factory injectors in three strokes!

I apprceiate anyones time for next diagnostic or repair steps. I am pretty handy wuth engines and am wondering if I could kit this pump myself or if the $600 exchange is the way to go (if needed).

Thanks... Steve

Clean the tank outlet. It's plugged. You may need to remove the valve from the tank and clean the tank. A quick and dirty trick is to remove the line and stick a blow gun to the tank outlet. Blow the crap back into the tank. If that gets you good flow for a while then that where the problem is... but it will reoccour. Should also be a screen on top of that tank shutoff valve...
Also... MAKE SURE you remove the fuel cap when you force air into the tank. It's NOT a pressure vessle...

Rod

have you checked the fuel filter and flow to it?? it could be full of water and crap as well as a problem at the tank.. bottom line is you need good fuel flow up to the injector pump.

Thanks for the quick replies. We had already put on a new filter and fresh diesel in the tank. I checked that we were getting fuel into and out of the filter but I have no idea what normal flow looks like.

I was trying to remove the fuel inlet line at the pump and the banjo bolt was turning but appears to have been stuck so the actual part it screwed into (mount?) broke loose from the pump housing. This part has a check ball behind it so guess we get to replace or repair this part also now. Anyone know if this part is available or how to reattach properly? Internet searches beginning

We will fix this and then drain and clean the tank and lines and report back. Thanks all.

Also check to be sure the fuel return line and fitting aren't plugged.

Thanks all for the helpful replies! After looking in tank you guys are probably spot on. We have repaired the fuel inlet and are cleaning the tank and lines tomorrow Really hopeful that this works and will post results this weekend.

Status... and round 2...

We cleaned out tank petcock, blew out the lines (main/return), another new filter, and re-bled system. No luck. Things improved some, but still have an issue where it won't reach full RPM's or run for long. Fule flows very quickly from all lines going to pump from filter.

It's either the injector pump isn't getting enough fuel, or isn't pumping enough fuel. It maintained about 600-700 rpm idle (with throttle on full power end) for approximately 3-4 minutes but would die at idle position. A couple of times its was able to reach 1200 -1400 RPM's for a few seconds before it idled down again. Verified that the rack arm is indeed moving properly btw.

Could there be an issue/clog in the very front part of the pump where the fuel inlet attaches (part is held on to the main body with four screws)? Thought about removing that and checking for obstruction in the fuel inlet area but otherwise I guess its pull the pump to rebuild or replace unless anyone has another suggestion.

Appreciate all the feedback and any suggestions.

Steve

blufie
Try running engine with fuel return line disconnected. Use a catch pan as fuel should come out of pump fitting while engine is running. If no fuel comes out of fitting you found your problem.

Jim, I need a little clarification... do you mean the return line on the side of the pump back to the filter, or the one attached to the injectors back to tank?

And if no fuel, is the pump the issue or something else (that maybe should be obvious to me but isn't)? ;-). Thanks!!

I was referring to the line that leaves inj pump and goes to the fuel tank filler neck by way of the top of the injectors.

So if the flow from the return is none or very small, does that mean the pump is bad?

It could mean the check ball in the fitting is plugged which could mean something inside pump is coming apart.

Thanks TxJim!! I'll look closer at all things pump related when our arctic freeze lifts.

One final question for now... Is it possible to remove and replace the pump without taking the front of the engine (timing cover) off or does it require radiator and everything removed?

Finally getting back to this project...

Can anyone tell me the shade tree mechanic way to R&R this pump? I have a manual but it calls for several specialty tools and such that I don't have. Do you have to pull the engine cover?

I know it is a lot to ask for shortcut instruction set or pictures of the steps but I would be greatful. If someone who has actually successfully performed the steps could provide them, I could provide some compensaton for their time and knowledge.

I there is no option but the manual way then I will just dig in and figure it out as I go.

Thanks All.