Stihl MS250 problem

[JoeBob99]

I've got an MS250 that was a gift. My friend cut up a few trees for his smoker and used vegetable oil instead of bar oil. I got the saw a year later with the veggie oil still in the reservoir. I burned up one bar before I realized it's not getting adequate oil to the bar. On one fuel tank, I've got to stop 2-3 times, remove the chain cover, and clean the area out. I ran the saw with no bar on and can see some oil coming out. It happens even when I totally clean the bar with rubbing alcohol and air compressor. I don't think the bar hole is blocked, I think there is an obstruction from the reservoir to the oiler. What do you guys think?

 

[Brent Nowell]

Vegetable oil when it sits in the right conditions can turn rock hard, especially with the heat from the saw.

 

[Wood Doctor]

Ran into similar problems with an 028 when a guy used 2-cycle engine oil in the bar oil tank. I had to dump it all out and clean out the inside with gasoline. That worked.

His saw had gotten so hot that it burned out the clutch needle bearing. He said, "I was wondering why it was smoking so much."

 

[JoeBob99]

I think that's what happened.

It's giving oil when there's no bar on the powerhead. I did the cardboard test with the bar/chain on. It threw a little oil all over the cardboard instead of the narrow, neat stain that I've seen in videos

 

[JoeBob99]

Oh shoot. My neighbor came over once because he could see the smoke. He lives a 1/4 mile away. This is my first saw, thanks for going easy on me.

Should I drain the bar oil from the reservoir, fill it with ethanol free gas, then run the saw a little bit under light load?

 

[stilh036prohog]

No rinse the oil tank with gas clean oil filter and refill with a thin down oil. Then test. You can use 5/20 motor oil.

 

[JoeBob99]

Oh shoot. I ran it a few times with the gas in the oil tank. Then drained the gas and let it air out. Added 10/30 and ran it, with zero oil showing up on the cardboard.

 

[stilh036prohog]

Ok. Is it the same bar on it from new? Y won't hurt the engine just the bar.

 

[JoeBob99]

No it's the second bar. The original one got totally gummed up at the tip.

I acquired the saw full of veggie oil. Drained it and replaced with Husky bar oil. I was cutting log rounds on a deck and the tip got totally frozen.

 

[Brent Nowell]

Second bar, is that new? Cause if that bar oil hole is clogged this will explain your problem

 

[JoeBob99]

The hole is definitely not blocked, on either side

 

[Brent Nowell]

If the hole is not blocked and you are getting oil pumped when the bar is off but not on then

-the pump is done, it is not pumping enough pressure
-the bar oil hole is not lining up to the pump output hole
-the bar plate and or bar is not clean or flush resulting in a poor seal
-there is a partial obstruction in one of the pump lines and or filter.

 

[JoeBob99]

I gave a super good cleaning, it's not the bar oil hole and the bar is flush.

I'm guessing there's in an obstruction in the lines or filter. If it's not that, I think the pump is done. I'm going to tear it down and I'll check back in

 

[stilh036prohog]

The oil pump might be to low.

 

[Ax-man]

Just curious are you still friends with the veggie oil guy. I would be mad . I f I ever lend a saw out which is rare I find some beater saw that way I am not out anything if it comes back broken and odds are it will be while in the care of another.

My guess is your oil pump is gummed up and some of those oil galleries leading up to the where the oil comes out to lube the bar and chain. You probably have already done this but you might as well tear it all apart and replace the pump .

 

[JoeBob99]

Ax-man I didn't word my post properly. It was his chainsaw that he put veggie oil in then he gave it to me as a gift. I watched a donyboy73 video on oil pump replacement and that's something I would like to do myself. Do guys buy parts at the Stihl dealer or online?

 

[Ax-man]

OEM Stihl parts are pretty much only available from dealers . Used parts are available online or aftermarket parts are online for Stihl machines.

I would say you got a good gift from your friend. If all you have to do is replace an oil pump which isn't hard to do is much better and easier than a saw with a roached piston and cylinder.

 

[JoeBob99]

Yah, if I was smart I would've signed up for this site a long time ago. I was really fooling with that saw for a while. I like doing mechanic work but my diagnosis skills are atrocious.