Appears you have lost the gear quadrant indexing for #1 cylinder. The quadrant is clamped to the pump plunger with a screw and have been known to occasionally get loose or was not tightened properly on assembly. Getting the indexing back is pretty tricky, sometimes by comparing with a known good pump or off to the test stand.
You could try moving the pump to another cylinder to see if the problem follows or you need to be convinced.
Hi Team,
once had a new machine with a louder injection noise to a cylinder.
By slowly cracking the injection line of the faulty cylinder --taking precautions with a rag held over the connection to the injector or pump end line nut to stop being sprayed with high pressure fuel--hazardous to your health and eyes-- as more fuel was bypassed the cylinder eased its noise and the engine became smoother--fix was to fit a new pump assem. on warranty.
A fuel pump test bench would be needed to re-adjust the plunger to quadrant gear relationship accurately.
Or you could sight the relationship of the gear split to the shut off slot--vertical groove at the top of the plunger--and start from there to adjust for even running--better still get a good used pump assem.
This problem often comes about when the pump plunger is stuck and the rack has been forced to turn the plunger to free it up.
Plungers can only be freed by first making them rise and fall--go up and down--then when they do this can the plunger be carefully rotated whilst it moving up or down.
Cheers,
Eddie B.
[quote="edb"]Hi Team,
once had a new machine with a louder injection noise to a cylinder.
By slowly cracking the injection line of the faulty cylinder --taking precautions with a rag held over the connection to the injector or pump end line nut to stop being sprayed with high pressure fuel--hazardous to your health and eyes-- as more fuel was bypassed the cylinder eased its noise and the engine became smoother--fix was to fit a new pump assem. on warranty.
A fuel pump test bench would be needed to re-adjust the plunger to quadrant gear relationship accurately.
Or you could sight the relationship of the gear split to the shut off slot--vertical groove at the top of the plunger--and start from there to adjust for even running--better still get a good used pump assem.
This problem often comes about when the pump plunger is stuck and the rack has been forced to turn the plunger to free it up.
Plungers can only be freed by first making them rise and fall--go up and down--then when they do this can the plunger be carefully rotated whilst it moving up or down.
Cheers,
Eddie B.[/quote]
Thanks guys, I have now tracked down a pump segment replacement, just wondered how my pump went out of sync, that screw that worked loose, does it locate the barrel in a fixed position pre set at the factory ? I guess by it working loose the internals of the pump can rotate putting it in a max fuel position regardless of the rack setting. is that correct ? So when I get the replacement,thats all I would need to do is to get the gear meshed into its correct position Thanks Martyn
[attachment=24003]RHPARK.jpg[/attachment]
My 1938 D2![]()
Update
I have managed to get a replacement pump for number one cylinder, on removal of rack , found that plunger is sticking solid on top of stroke, also the lifter "cup" is broken on one side. Do these screw out of the lifter to replace this part ? Any exploded drawings of the pump ? I have now freed up the plunger, so it returns fine now but need to replace the lifter top.
Thanks
Martyn
Yes Martyn, they do screw out, try and hold the lifter yoke while you loosen the locknut, then unscrew it and fit a replacement, then it will need adjusting, set on TDC at the flywheel mark for that cylinder with both valves loose and adjust the height of the yoke with a depth Michrometer, you will need one with a small diameter rod to fit between the side of the yoke, The specified measurement is from the middle of the yoke to the top face of the fuel injection pump housing, O.M may have the measurement, but failing that, I do have a couple of contacts who may still be able to help.
I've been thinking Martyn, when you clean the flywheel to find the TC marks, look out for a 'lifter setting' mark just in advance of TDC, its a long time since I did this on any Cat engine (1969) and something tells both marks exist, also when you have set the lifter, turn the engine the 'normal' way and the lifter should rise a bit more, which is the final check that you have done it on the right stroke.
Hi Martyn,
scans below from the yellow SRB should help.
Lifter height is 1.741", this would give injection timing at 24Deg Before Top Dead Centre.
Cheers,
Eddie B.![]()
That's spooky Edb, I was going to write down 1.741" but it I over 15 years since I had reason to look up the measurement and the memory isn't as clear as it was, hence the reason for checking the timing marks for 'lifter setting'.