Perkins Diesel - Starting / Running Issue

[V8RX7]

Hi

I'm hoping someone can help, I have a '93 Manitou telehandler with a 4cyl Perkins diesel that I've owned for years without issue - it always starts immediately.

The other day it died whilst idling.

I found it had lots of air in the diesel system.

I cleaned & tightened everything and there is no more air albeit I didn't find an obvious problem

However it simply will not start unless I squirt some diesel into the intake manifold - then it starts immediately.

It will also randomly stall on idle and is clearly down on power - try to use the ram and drive and it will stall.

I have cleaned and checked the filters, cracked the injectors multiple times and bled it for hours.

I've cleaned the gauze filter in the lift pump and the fuel / fuel filter are clean, I've even cleaned out the tank (hardly dirty) and blown the lines through

What have I missed ?

Thanks

Am I correct that the 5th injector mounted on the inlet is for cold starting only ?

[V8RX7]

But that's the thing - there is no air in there (that I can see)

Above the filter there is a distribution block.

It was bubbling out every time I loosened the input nut - it doesn't now (nor at any of the other points)

I ran the machine for 8 hrs yesterday - just I had to restart it using diesel - about 50 times

I've cracked the injectors when it's running and all cylinders are firing.

I have a mechanic coming out but I've already waited a week for him

[V8RX7]

I had thought about a temporary tank but after (apparently) fixing the air in the supply line I moved on.

There is certainly return fuel at idle - I guess there should be even at full throttle - if not then either a filter is blocked (they aren't) or the pump is duff - is that right ?

Annoyingly I had a similar problem when I bought it - no power. That turned out to be 2" of crap in the bottom of the tank - I cleaned the tank and changed all the filters and it's never had an issue since.

[V8RX7]

C Lee Farquar said:

You've done the obvious so, assuming you haven't made an error, I would change the lift pump next. Or rig up a temporary electric one to see if that makes a difference.

Would you ? (serious question as I know nothing about diesels)

The lift pump draws through a water trap - that is full of diesel and then supplies the filter - that is full of diesel so unless either is emptied at full throttle surely it must be ok - or doesn't it work like that ?

[V8RX7]

I found the issue with mine was there was a final filter in the fuel pump (after the incoming fuel line, within the pump).

Only a little bit of crap in it - but enough to cause an issue.

Cleaned it out and all good.