Injector issue

[Yannp]

Getting to the point to try to test my major. First run for 10 years. Bleeding fuel system. Just can’t get fuel out of cylinder 3 injector. Is there any easy way to clean injector pump or do I have to strip the whole thing?

[Billy26F5]

Clean the pump exterior thoroughly and make sure no dirt of any kind can get anywhere near the pump before you open it. Remove the inspection cover and turn the engine by hand, when you get to no. 3 filling (during no. 4 injection, firing order 1-2-4-3). You might find that plunger no. 3 is stuck, you should be able to get it moving. Don't move any of the bolts on the rack or the maximum fuel stop, otherwise you'll need to recalibrate the pump which is very expensive. If the plunger isn't stuck the pump will need an overhaul, also very expensive.
Sandy

[Yannp]

Thanks. Will try.

[mathias1]

Yann,

also check the pipe between the pump and injector is free.

[Yannp]

Had checked pipe and ok. Just taken off cover and found it is stuck. Need to try to free.

https://youtu.be/OaWJwNSBK1o

[Billy26F5]

That's cylinder no. 2. The numbering is from the front.
Sandy

[Yannp]

Ok. Thanks. Trying to crank to when the metal coil should be down and then gently press it down.

[Old Hywel]

Once had all six plungers stuck on a BMC 5.1 (CAV pump). Assuming that we couldn’t make things worse, some fairly rudimentary methods were employed to ‘persuade’ them to loosen up. Pump was removed, and I think the pump was split to allow access.
Lack of oil and lack of use probably caused the problem. Worked afterwards.

[Billy26F5]

If you do take it apart, don't touch the rack. Don't mix the plungers either as they will only fit their own barrel. And make sure no dirt can get anywhere near it. If you can manage without dismantling it any further it will be much easier to keep clean and undisturbed.
Sandy

[shepp]

If the tractor has not run for 10 years and there is no obvious sign of water and corrosion in the pump chamber it is likely that the plunger has seized in the barrel through "gumming up" - that can happen with diesel fuel as well as petrol. The machining tolerances between the plunger and the barrel are so fine that it only needs a small amount of gumming for the plunger to stick. Try a hot air gun ( not a blowtorch!) on the element that is stuck and carefully try to press the plunger back down after it has warmed up some, keep a constant straight down pressure on whilst continuing to warm. If this does not work thoroughly clean the area around the pump injector unions, remove number 3 injector pipe and carefully remove the delivery valve from the pump taking care not to drop any parts. You can then flood the plunger and barrel assembly from above with a good quality penetrating oil and allow it to soak in for a day or two before trying to free the plunger again.

[Yannp]

Lots of wd40 and using the spring to flick down once the metal coil had dropped. Finally freed and ending running well now. Thanks.

[henk]

Always glad to read that a Major has been brought to live again.

[leeroy]

Would a FMD run with a stuck plunger?
When I replaced fuel line It didn't prime on one injector, but fired up so I quickly snugged up that line.
It does seem like there is a skip in it.

[Hair Bear]

Yes, it's the same effect as popping a plug lead off a petrol engine. Easy to spot, just take the side plate off the pump you'll see the four little plungers, start the engine and you'll soon see if one plunger isn't moving. Ours originally had three stuck but it still fired up on one cylinder! Freed the others off and runs as you'd expect.