345 will not pump oil to the bar

[bertsmobile1]

OK fellas, I am stuck with this one
Got a 345 in the shop
originally it had a broken piston which killed the bore as well
Replaced the barrel , piston bearings & seals
Saw runs perfectly
But not a drop of oil to the bar
1) pressurised the oil tank & oil ouzed out around the rubber seal, so replaced the seal-no change
2) replaced the spindle - no change
3) removed the filter , it was clean
4) replaced the entire pump, worm gear & another rubber seal, still no oil

The only non standard thing is the drum which is now a rim sprocket in place of the spur sprocket , but I have checked the drum is triving the oil pump worm gear
This has the cheaper pump with no flow adjuster .
As this is mainly a mower forum I have also posted to OPE
I would rip my hair out but it is all gone already .

Any one got some ideas ?

 

[StarTech]

There is a several combos you could be needing here.

Lets start with which drum PN and Oil pump drive pinion PN, you installed. I assuming you used the 345 non adjustable oil pump.

so are you using the 503931801 pinion that has the spring wire drive? Also do you that 508240905 pin installed? If the dowel pin (low right of the image) is missing the oil will not work.

 

[bertsmobile1]

Thanks Star,
It is actually a 345e and yes it is the lower right set up that snaps into place
As for the dowel pin 503 24 09-05 there was not one in the original pump and I can not see where one would go
There are no holes for it as everything snaps into place but I will be going down stairs in a while to strip it apart for the 22 time so will get the magnifier out and a strong light
If it is just a missing dowel I will be in 7th heaven as this saw has been here for over a year.
The owner moved before I got the engine parts in and only comes down here once or twice a year . As of now I have over $ 300 invested in parts
I am a bit miffed as the where the dowel would go & what it would do
The pump case 537 15 48-01 is retained by the slot it fits into & has no for or aft movement possible
The shaft 537 93 20-01 has a groove that runs between a pair of protruding rods so is also constrained .
There is always the possibility that there was one which fell out unnoticed by me during disassembly but I usually do that inside a box because I have been caught out before with bits I did not know where there falling out & vanishing to the 5th dimension along with all of the missing keys & left socks .

 

[StarTech]

this where the pin goes. Used drill bit so you could see the location better. This image is from a 435 but the location is the same.

 

[bertsmobile1]

Thanks Star.
Amazing how you can fig around with something all day then remember it wrong 9 hours latter
Yes the pin is there sitting in the groove in the shaft where it should be , I just remembered it wrong .
After lunch I will cut town an old socket to fit into the pump worm sleeve so I can test the pump properly with a power drill.
I spun it ( sort of ) just pushing down on the drum & I did get a tiny trickle out of the pump so I will see what I can get at 3600rpm that the mains drill can spin at
And double thanks for the photo as the drum I have fitted has a drive slot that would obviously fit the worm's drive tabs on the 435 in your photo.
Now burning question
What is the worm like on that drive ?
The ones I have are use spiral wound wire and do not make good contact with the teeth on the pump shaft