Stihl MS250 not oiling

[Wolfen]

Hi guys, its been a long time since I worked on a chainsaw and I have never messed with Stihl.
I have two gas saws, one is a MS250 the other is a MS290 Farm Boss, I'm in the city of Va beach so I don't need anything bigger to get firewood, but the other day i noticed that my 250 stopped oiling, I checked the tank first and yes i has oil, so I took off the bar and chain and cleaned everything and still no oil, next I took the strainer out of the tank and cleaned it too.
Y'all got any ideas cause I'm really not into buying another new bar since the bar thats on on has only been flipped once

 

[cedarshark]

Could be several things:
1) Tank vent plugged
2) Oil hose fell off the bottom fitting on the pump.
3) Oil line from the tank to the pump is plugged.

Is it pumping/leaking oil under the saw ?

Buying a new bar will not fix your problem. Did you run the saw with the bar off ? Is it pumping oil when running just off idle when the clutch is engaged ?

 

[chainsawman2011]

pull off the sprocket and clutch and take out the plastic worm gear that drives the pump if the threads are bad on the plastic worm gear replace and reassemble and see if it oils. also when you have it apart make sure the plastic casing by the oil pump is not ate out and destroyed. this happens when the sprocket bearing goes bad and sprocket tips and digs the wire part of the worm gear into the case. also a good sign that this has happened is that it spews oil out below sprocket. instead of up to the bar plate

 

[AKDoug]

First step. Run the saw on the bench at half throttle without bar/chain/side cover and see if there is oil coming out of the oiler hole.

 

[Wolfen]

Thanks guys
1> tank vents properly
2>oil hose from pump to tank is connected
3>Nope, not plugged
I bench ran it with no bar and no oil came out, the plastic worm gear is there, but it looks like is is worn out completely, so a new one is on order since the local dealer is out of them at the moment.
Thank you VERY much guys, yall are lifesavers when it comes to my saws

 

[Patrick1903]

@Wolfen I realize this is 7 years old. Did this solve your piling problem on the MS250? Just trying to see if this was the problem. I have MS250 that is intermittent. Saw is 4 years old with probably less than 10 hrs.

 

[KASH]

bump.

 

[wkeev]

I had one that wouldn't oil . I replaced the rubber oil line and that solved the problem. I think they shrink and suck air instead of oil .

 

[Patrick1903]

Thanks. I was cutting with my MS250 last weekend and it wasn’t piling great, or didn’t seem to be. Bar got pretty hot and started smoking. I cleaned bar out with air and it seemed to start oiling some then. But not as
Much as I would have thought. I considered the hose on mine but it’s only 3 years old. Fixed a 15 year old MS180 that was doing just as you describe. Also leaking oil out of the bottom. Hose was definitely hardened and not sealing. Easy fix after taking the handle off.

 

[a. palmer jr.]

The small Stihl saws don't oil like you think they should..

 

[Patrick1903]

The small Stihl saws don't oil like you think they should..

Anything that can be done to help the saw out? Would a thinner oil be better?

 

[a. palmer jr.]

Anything that can be done to help the saw out? Would a thinner oil be better?

A thinner oil might be okay in winter. Just make sure everything is clean. There is a little plug in the oiler passage near the left of the muffler, make sure it's in place. You can take that plug out and put a thin piece of electrical wire in it to clean out that passage, then put it back. It's real easy to replace the oil pump if you think yours is worn out.

 

[Patrick1903]

A thinner oil might be okay in winter. Just make sure everything is clean. There is a little plug in the oiler passage near the left of the muffler, make sure it's in place. You can take that plug out and put a thin piece of electrical wire in it to clean out that passage, then put it back. It's real easy to replace the oil pump if you think yours is worn out.

I really doubt mine could be worn out since it’s probably got less than 5 tanks through it, and it’s 3 years old. I’ll look for that plug and make sure passage is clean. Thanks.

 

[HarleyT]

Run it with the bar/chain off to check the flow. Rinse out the tank with gas mix, slosh around, dump, repeat. Then run the saw with gas mix in the oil tank, it helps break up clogs.

 

[irhunter]

I really doubt mine could be worn out since it’s probably got less than 5 tanks through it, and it’s 3 years old. I’ll look for that plug and make sure passage is clean. Thanks.

Posts 2-5 and 14 give a nice run down of the things you might need to check. Start, perhaps, with the vent...but, thinner oil is probably not the solution.

 

[Reesedlightning]

I just fixed an older 021 that actually had an oil adjuster but I know that many of the homeowner saws do not have that. It too was not oiling at all and the issue I found was that the bottom of the little oil pump was clogged with gunk.
This video is pretty helpful.

 

[HarleyT]

How was it adjustable?

 

[Reesedlightning]

How was it adjustable?

Had to go back and look through pictures. The 039 has an adjustment. Not the 021. My apologies. Had them both on the bench at the same time. The 021 did however have the clogged oil pump. Small amount of crud packed in the bottom

 

[HarleyT]

Had to go back and look through pictures. The 039 has an adjustment. Not the 021. My apologies. Had them both on the bench at the same time. The 021 did however have the clogged oil pump. Small amount of crud packed in the bottom

Yeah, those little pumps clog easily.

 

[Captain Bruce]

A thinner oil might be okay in winter. Just make sure everything is clean. There is a little plug in the oiler passage near the left of the muffler, make sure it's in place. You can take that plug out and put a thin piece of electrical wire in it to clean out that passage, then put it back. It's real easy to replace the oil pump if you think yours is worn out.

That little plug is the duck-bill vent...and it plugs up. The supply line could be collapsing from vacuum in the tank.....the gear teeth are worn, allow the pump to slip, instaed of engage....tank has a pick-up/filter......and try using the thinnest oil you have around, after checking the oil system end to end. If it oils, go back to bat oil, and never look back.