Dang 681 oiler!

I have a Solo 681 that wont oil. I checked the tank vent, inlet tube and outlet tubes are clear, tank inlet screen is clear, swapped oil pumps, checked oil pump drive (its has a similar setup to the husky 372) and its spinning the pump just fine, what gives? Is there a check valve built into the pump? Anyone have any ideas?

Is the worm gear engaging the drum ok? Have you tried turning the worm gear with the pump bolted in tight? I had a 372 once that the worm gear wouldn't turn when the oil pump was bolted in, but would when the oil pump was in my hand. It turned out that the PTO side seal wasn't driven in deep enough and the worm gear was butting up against it.

Hi Jacob J! Yep, I can spin the pump gear easy with my thumb when the pump is out of the saw, the plastic worm drive gear looks fine, and spins fine when its assembled in the saw and it has that slight resistance to it so that you can feel it driving the pump as well. The one thing I didn't check was how it spins once the clutch is installed, I'll go try that...

Well, I rigged up a way to spin the drive gear with a power drill, which got the drive gear spinning at 1500 rpm or so, which should have definitely got the darn thing pumping some oil, but nothing. When I spin the pump impeller with my thumb on a Husky or Stihl pump, I notice the resistance changes when you turn the adjusting cam from minimum to maximum flow, where as on this Solo pump, it did not.
So, I thought it was worth taking this Solo pump completely apart, which meant I would have to press these incredibly tiny pins out, and the effort was well worth it... I found the plastic (Plastic?!) adjusting cam (these cams are steel on both Husky and Stihl saws for a good reason!) was completely worn away! The pump impeller rides on this tiny plastic "nub" (which as you know, is what makes these things pump oil) is now nearly gone (the only way I could see it clearly was to use a giant magnifying lamp, my eyes are going downhill fast, lol).
That's a poor design by Solo in my opinion, but I will probably have to order a new pump and have that one wear away in 6 months as well (maybe they designed a new piece, we'll see). The only other option is to machine a steel adjuster, but I don't have the necessary equipment or time to do that.

Already on the second page -nobody likes my threads. Stop crying Chris, -get a grip....

Anyway I found the cure and have photos as well, so if anybody has this issue they won't have to go through what I went through, (as long as they do a search):

This is the before photo, Notice that plastic "nub" is virtually worn away...

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Here's the cure: I drilled down the plastic shaft using a 1/16" drill bit and then used a #4 self tapping screw, then I cut the screw, using a die grinder and repeatedly cooling the cut by dipping the piece in water so I won't melt the plastic. Then i ground it to correct length using the same cooling process, then ground the pin's surface to a smooth finish using a diamond plate.


<a href="http://s518.photobucket.com/albums/u349/skippyktm/?action=view&amp;current=PICT4733.jpg" target="_blank"><img src="http://i518.photobucket.com/albums/u349/skippyktm/PICT4733.jpg" border="0" alt="Photobucket"></a>

Pumps like a bastid' now... Prolly last a heck of a lot longer than the original.:biggrinbounce2:

C'mon guys I put some effort into this. Won't you just humor me a little?

Plastic not a good idea in that application. Good work getting it going again.

Good job> I read your post this am. I had the same idea you had while @ work, but saw you had it done already the next time I checked your post. How many hrs. do you think that saw has on it? The have a partner 500 that has a plastic pin to work the pump. I wonder if summer bar oil in cold temperatures puts too much load on the pin?

This saw is a logger's saw, and its about 3 months old, so I would say about 300 hours or so. They were running winter oil in it now. This is the second pump to fail (they had some older dead ones, from last year... RIP), they currently have 3 681 Solos and the other 2 are 2 months old so I expect the same thing to happen to those pretty soon...
I do believe Its a gradual thing, the impeller just grinds away at the plastic nub, and the loggers keep cranking it up to compensate until its gone.

SkippyKtm said:

C'mon guys I put some effort into this. Won't you just humor me a little?

Click to expand...

It looks like your effort paid off. How about I humor you with some rep?

I'm also curious about how many hours it took for the pin to wear away (edit--nevermind, I'm just read your post). BTW, did you ever check to see if Solo offered an improved/sturdier oiler?

SkippyKtm said:

This saw is a logger's saw, and its about 3 months old, so I would say about 300 hours or so. They were running winter oil in it now. This is the second pump to fail (they had some older dead ones, from last year... RIP), they currently have 3 681 Solos and the other 2 are 2 months old so I expect the same thing to happen to those pretty soon...
I do believe Its a gradual thing, the impeller just grinds away at the plastic nub, and the loggers keep cranking it up to compensate until its gone.

Click to expand...

I wonder if the same part out of a Dolmar oiler (6400/7300/7900) could be adapted into the Solo pump? Your fix is ingenious but it may be easier to put the Dolmar adjusting screw in there.

Chris J. said:

It looks like your effort paid off. How about I humor you with some rep?

I'm also curious about how many hours it took for the pin to wear away (edit--nevermind, I'm just read your post). BTW, did you ever check to see if Solo offered an improved/sturdier oiler?

Click to expand...

I like rep, I shot ya some back, thanks!

Jacob J. said:

I wonder if the same part out of a Dolmar oiler (6400/7300/7900) could be adapted into the Solo pump? Your fix is ingenious but it may be easier to put the Dolmar adjusting screw in there.

Click to expand...

I do have a Makita 6401 that I could see if its swappable...

That adjuster looks exactly like the one I replaced on the Makita 6401, I couldn't adjust the oil flow rate,when I took the pump apart,I found the little nub was worn down to nothing.

Part wasn't that pricey, but is still all plastic, so it will wear down again, time will tell on how quickly though.

Well, that's good to know that it will be a waste of time to check the Makita oiler, as its the same darn thing! Well this 681 is a loggers saw, and gets about 5 hours use a day, so in around 3 months or so, we'll find out how it holds up.

I rep'd ya. Good work mate! I also messaged a seller on Ebay that was selling his Solo 681 because he had oiler problems. I directed him to this thread, so you may have helped another Solo logger as well :msp_thumbup:

Great job!!!!!!! Thanks!!!! Awesome repair!!!!!!!!!!!!! Good to know as I have 1-665 converted to 681 and 2-6401's converted to 7900/8400.
Shep

Skippy, Is there anyway you could reload your pictures? I am going to try your fix on a 6421.

Here are the 2 that I find. Forgive me for cropping the background away, it makes for smaller file size.
....and trust me when I say that I'm a nut for big pics and lots of detail, so cropping is not something I take lightly.

I haven't seen the oiler mentioned here, but I wonder what part wears out next
from the change.
How hard is it to replace this part versus the difficulty of changing whatever it rubs against, if that part now wears out?
It can seem a bit crazy or aggravating, but sometimes a material choice is made based on replacement/maintenance issues.

Thanks for the pics. I understand that the screw may be the issue so wondering what is supposed to look like. Now i have an idea