Injection pump checklist- hard to start

Great Oak

Member
Having issues with tractor not starting have had to pull start it to get it running.
Tractor MF 360 diesel perkins- cav pump
when it's running it runs great but after a while will start sputtering and then die. Tried pull starting this morning and wouldn't start.

Have bled air out of fuel lines, changed air filter checked for obstructions. Preparing to change fuel filter.
what my best way to troubleshoot this and does anyone have idea if the fuel tank has a filter in it as well?
where is the bleed screw on the cav fuel pump? there's lots of knobs on that pump. Not sure which one is bleed screw.
 
replaced fuel filter and it was clogged with what appears to be dirt and rust. Now have primed pump and still wont start either by battery or by pull start. Please advise what might be next steps.

I am wondering if I got dirt in injection pump and if there are any other filters needed to check.

possible next steps are to pull injectors as well.
 
If there were LOTS of dirt and rusty fuel the injection pump may be seriously damaged, depends on how much got inside. If the rotor plungers are stuck like most pumps I see it may work again with a complete tear down and cleaning, providing the head/rotor assembly is not seized..
 
Thanks Dieseltech. Is there any diagrams on how to disassemble & clean the injection pumps?
I pulled injectors and cleaned gunk off of them. I will check tomorrow and see if I am getting any fuel I think the injection is probably the issue and clogged with junk.
 
Here are the bleed screws, no need to remove them just loosen them. Unless you really know what you are doing I would not attempt to actually strip that pump down, they are a real specialist job!

<image src="http://forums.yesterdaystractors.com/photos/mvphoto25558.jpg"/>
 
I thought so as well. In depth and more of a full on instructional- repair than others I have seen which are very basic.

I superficially cleaned the injectors and saw lots of black gunk near tips. I think the injectors just might be clogged but not completely sure. Anyone ever take the injectors apart before? Is this something that can be done? Looks like original injectors so it may not hurt to purchase new ones.
Read about ways to test if injectors are getting fuel but wanted to see if anyone had any better methods in doing so. Issue with the test is you almost have totally remove fuel tank to get to injectors and then hook the system back up to determine if its spraying fuel.
 
IF the injectors are really stuck then there's a good chance the pump head is seized. Unless you have an injector tester I wouldn't take the injectors apart. There are tools to repair pumps and injectors, and without them there's a risk of damaging expensive parts. I cringe when someone brings something to repair after they've had it apart, may have parts missing, or damaged. Then have to explain why it's going to cost so much to correctly repair it. Knowledge is great, but proper tools are important too.
 
I have to agree with Dieseltech, take them to shop that works on them, and have them tested before you spend $225.00 or more each for new ones.
 
One of mine has that close-fitting tank, so I bypassed it temporarily. Hung a CLEAN gallon plastic jug with some fuel on a wire from the ceiling. Ran some clear plastic tubing (secured into the jug with wire)to the fuel pump and bled the system.

Loosened the nuts on the fuel lines feeding the injectors, throttle wide (for more fuel delivery)and cranked over. Spray is visible if working.

A time-saver I've found - when bleeding the system, if the fuel pump actuating lever is sitting high on the lobe of the camshaft you get only a very small bit of fuel from the priming lever. It moves maybe an inch, and it moves a bit harder when pumping. If you get a quarter inch or less pumping action, it's high and you'll pump all day. Turning the engine over 1 rev will give you more delivery per stroke.
 
update: I safely disassembled and cleaned the injectors. Had one cogged nozzle- sonic cleaner purchased from harbor freight with degreaser di the trick.
had to pull start it and once air was out of lines it runs great. YET upon turning it off it wll not restart. I am sure can pull start it again but that's a pain.

I think it might be the injection pump. not sure. anyone else had this issue where you had to pull start the tractor? I will perform a batteryload test tomorrow.
 
Latest update and AAR:
Got advice from old timer tractor mechanic at local shop who diagnosed that I needed to tap on the fuel injection pump because to him sounded like the low lubricity in fuel was causing the tractor shutoff lever to stay in shut position. Sure enough he was absolutely correct. Tapped on fuel pump with pocket knife near area where lever on pump shut off and tractor fired right up. Runs great now.
lessons learned
1. Fuel injector cleaning- recommend- get a ultrasonic cleaner and clean before buying new ones. Not that detailed on the injectors components
2. add fuel lubricant to tractor fuel for diesel
3. Saved a ton of money doing work myself which did not require injection pump rebuild. Thank the Lord.
 

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