Perkins 4108 will not start

[a64pilot]

The injectors are spring loaded shut, so that the pump has to exceed the cracking pressure to open them, so in effect your correct, the pressure does build up in the injectors.
However from the white smoke, I would say that your getting fuel.
I think your correct to be suspicious of timing, once your sure timing is correct I’d check compression. Yes it certainly should be good, but it’s easy to check and eliminate.
Three things required to make any engine run, fuel, air and fire. Fire of course in a Diesel comes from compression.
I wouldn’t hit it with starting fluid myself, I’d verify timing.
Since it has been apart, it’s possible the camshaft is out of time too. I’d verify that after fuel timing.

I don’t know about a Perkins, but on some engines it’s not hard to set the timing to TDC exhaust stroke as opposed to compression, and be 180 out.

[model 10]

You need the service manual.
The marks on the fuel pump mounting mean nothing if the pump drive gear under the timing cover was removed.
You need to remove the cover on the fuel pump (under the return line) and align the proper marks. There are several marks and you need the manual to decide which one to use. My 107 uses the edge of a snap ring and a mark inside the pump.
The pump drive gear under the timing cover is attached with slotted holes that are also an adjustment for the fuel pump timing.

[kinggeordie]

Originally Posted by a64pilot

The injectors are spring loaded shut, so that the pump has to exceed the cracking pressure to open them, so in effect your correct, the pressure does build up in the injectors.
However from the white smoke, I would say that your getting fuel.
I think your correct to be suspicious of timing, once your sure timing is correct I’d check compression. Yes it certainly should be good, but it’s easy to check and eliminate.
Three things required to make any engine run, fuel, air and fire. Fire of course in a Diesel comes from compression.
I wouldn’t hit it with starting fluid myself, I’d verify timing.
Since it has been apart, it’s possible the camshaft is out of time too. I’d verify that after fuel timing.

I don’t know about a Perkins, but on some engines it’s not hard to set the timing to TDC exhaust stroke as opposed to compression, and be 180 out.

Thank you Perkins timing on the cam shafts is pretty straight forward how ever the pump is slightly different I bolted it back on in the same position but wasn’t sure if to remove the inspection cover to this. As far as I could tell this could only go on one way as the pump is splined and keyed the other thing I thought about may be the pump may pumping on the exhaust stroke, I was told that the pump may be pumping to the wrong cylinder but couldn’t see how that’s possible if the cam timing is right, I had the back lash checked out on the timing gears, does the pump do one revolution to get back to cylinder 1 and 3?

[georgeg305]

Another possibility that occurred on my Universal M-25. I had a loose hsse clamp that was sucking air. The injector pump pulverized the air and "foam" was being fed to the injectors. The foam bubbles thru off the timing to the injectors so the pressure pulse were delayed past TDC enough so the engine would not fire. Kind of like delayed spark on a gas engine

[Milko Berben]

One of the first engine's i overhauled was a Perkins and it was a right bastard to start as it was first 180 deg out you will have to open the pump to be able to see it on the side there are marks with letters. And soak a rag in petrol during cranking hold it over the intake do NOT use the pre-heat in that case.

[kinggeordie]

Originally Posted by georgeg305

Another possibility that occurred on my Universal M-25. I had a loose hsse clamp that was sucking air. The injector pump pulverized the air and "foam" was being fed to the injectors. The foam bubbles thru off the timing to the injectors so the pressure pulse were delayed past TDC enough so the engine would not fire. Kind of like delayed spark on a gas engine

It’s worth checking out, the pump bleeders run clear in a good steady stream thanks

[kinggeordie]

Originally Posted by Milko Berben

One of the first engine's i overhauled was a Perkins and it was a right bastard to start as it was first 180 deg out you will have to open the pump to be able to see it on the side there are marks with letters. And soak a rag in petrol during cranking hold it over the intake do NOT use the pre-heat in that case.

Thanks does the pump, pump every 180 degrees to cylinder 1 and 3 then 180 to 2 and 4 and is 1 revolution on the pump moves the inners 360 degrees

[a64pilot]

Originally Posted by kinggeordie

Thanks does the pump, pump every 180 degrees to cylinder 1 and 3 then 180 to 2 and 4 and is 1 revolution on the pump moves the inners 360 degrees

Not sure what your saying, so I’ll just try to explain.
The pump turns just like the cam does, at 1/2 engine speed.
That way every stroke to pump fuel actually occurs every other time the piston is at TDC.
That is why it’s usually so easy to time one 180 out.
Usually the timing marks line up at every crankshaft rotation, it’s your job to ensure it’s at TDC compression and not TDC exhaust.

Good thing is I have never heard of any damage being done if it’s 180 out, where if you get the cam out of time, you can bend valves.

[artisanmach]

I have a copy of the CAV workshop manual
send me a PM and I will forward it to you

[waterman46]

Did you check TDC of cylinder using a probe vs valve opening positions? Maybe timing chain put on wrong at rebuild..

Crazy idea maybe. What was compression reading?

[rbk]

The other issue could be the pump. There are cases where the pump has been rebuilt but not timed to TDC. Where did you have it rebuilt/bought? If its not the timing, inj pump install then very well could be the pump itself.

[rbk]

Also you didn't mention which inj pump you've installed...CAV, mech or Hydraulic, or possibly a lucas which requires additional steps.

[model 10]

The timing cover has a bolt that is also a timing pin. You back the bolt out and it locks the damper at TDC. You can only turn the engine by hand to do this and it would be pretty obvious if you were on the compression stroke. It takes a pretty good size wrench to overcome the compression.

[NYSail]

Kill switch is in the correct position.....

[stnick]

My 30 year old 4108 always loves her fuel . I used to bleed and bleed. Than i had enough ! i installed a electric fuel pump after the fuel filter and just before the manual fuel pump . That girl gets fuel forced down her throat now. Try some starter fluid ! Shut the water off first so you dont force water. Than open once started. ! Best of luck