290 oiler issue

[pabst79]

So down in the 390 thread Joe explained in great detail about the wire and clutch drum, but I'm still having an issue, the one pic shows the wire between the outside of hub and chain brake band, the wire spins freely around the drum and I assume needs to be in that slot Joe talked about? How does the clutch come off? Or can I fix it without pulling the drum. Or or do I tie a rope to it and use it as a anchor for my boat? :( :D

  

 

[limbwood]

I use a small impact gun with 3/4 socket in reverse lefthand thread, sometimes the plastic gear gets wore, sometimes the wire spins on gear to easy and wont turn pump

[pabst79]

That's what I'm wondering, I can spin that wire around freely, doesn't feel like its grabbing or moving anything. ???

[joe_indi]

That's what I'm wondering, I can spin that wire around freely, doesn't feel like its grabbing or moving anything. ???

That wire should spin freely. Otherwise it's plastic portion would melt at full revs from friction.The wire has a worm drive that acts as a reduction drive for the oil pump.

[pabst79]

Joe, I tried spinning the drum, each way with oil in the slot,and making sure the wire was moving with it. It didn't suck any in or push any out. Is it most likely the pump or gear then?

[sablatnic]

Most likely the gear. It doesn't cost much. :-)

[pabst79]

Ok, i will pull it apart tonight and see if I can find out. 

[joe_indi]

pabst79,
It could be both or either of them. Unless you have that clutch out you wont be able to find out.
If the pump piston(a rotating shaft) is stuck for some reason, the worm gear would just strip off.
So you will need to replace both of them.
Worm gear usually need replacement by itself only if, for some reason, the driving wire(called worm spring) was damaged. That usually happens if the clutch or drum is worn out.

[pabst79]

Ok, still a mystery?? Here are some more pics. The plastic gear and pump gear move freely and look good, nothing seemed clogged and when I tip saw over, oil runs out the oil feed line? Hmm


  

  

  

 

[joe_indi]

 

[pabst79]

So I tried the oil, it came out where it was supposed to. I'm now wondering if the wire wasn't attached to the drum when I tore it down? The weird thing is that the saw never oiled well since new, but I know the 290's were known for that, but eventually it quit oiling all together, I took it to a dealer, they tore it down , said it was fine. I got it back and sawed a bit, it seemed like it might have oiled for the 1st few cuts, then it quit and started burning up chain. Here is a pic of adjuster. Thanks for the help!

  

[joe_indi]

Okay, adjuster screw is at Max. The pump is pumping oil. And the inlet and outlet passages are clear. The only things left are the clutch drum and worm gear that drives the pump.
If there is too much wear on the drum in the area where the needle bearing seats, it would rock around too much causing the worm to dis-engage often. Similarly, if the wire of the worm gear is worn or out of shape, it will not remain in its slot on the drum.
In such cases there are two things I do to the wire. Look at these images. Try it and see if it cures the problem.
Good luck.

[limbwood]

if you hold the plastic gear you shouldnt be able to spin wire around it very easy, if you can turn it easy the wire will spin but not turn gear or pump.

[pabst79]

So I finally put it back together and bent the wire as Joe showed and saw works great, Thanks for the great info Joe! 8) Others who have 290's will hopefully find this thread helpful as the 290's had dumpy oilers to begin with. 

[joe_indi]

pabst79, so glad things worked out. But I think you need to replace the clutch drum and needle bearing soon. Actually the oil pump on the 029/039 are  quite similar to those on the 460/461 and are very sturdy. The weak link here is the pump drive, which has issues when the clutch drum starts skaking on the crankshaft.