Stihl 390 Oiler Issue

[Homelite]

Contrary to other posts on oiler issues, my oiler seems to put out plenty of oil, however, it doesn't seem to lubricate the rails on the bar and collects around the back of the bar, near the adjuster. I have checked to make sure the bar is clear of debris and the bar galley holes connecting the oiler output to the bar rail are clear. A properly oiled bar and chain should fling oil off of the tip of the chain; however, with the oil collecting at the back of the saw, it doesn't seem to be reaching the tip and overheating the bar and chain when cutting. I am running a 24 inch bar with milling chain for my Alaskan mill, and have been for 8 years and this is the first issue I've had with oiling.
I am going to try a shorter bar with ripping chain to see if it works to try and eliminate potential issues (chain or bar). I am also looking to try and use a thinner bar oil (like Stihl winter weight) to see if it will help. With most issues on the forum being related to no oil, I'm curious to what I can try. I have had the oiler rate maxed out since I bought the saw due to it being used for milling, but have never had an issue. The flow rate seems even and consistent. The only change I've made in the last couple of months is the bar oil, but I have used plenty of different brands over the years without issue, even during the winter.

 

[stihl for life]

I would try thinner oil . the worm gear maybe starteding to wear out . now for the other note a 24inch bar is a lot for it to handle let along on a saw mill . that saw must but tired by now .

 

[Gypo Logger]

Check your DL count. To many DL's can compromise BL flow.

 

[anlrolfe]

Make sure your bar studs are driven in tight and haven't loosened up over time. If they back out they can hold the bar away from the frame enough to prevent a correct seal and leak.

Make sure your bar matches the bar stud style. If its held out .... same as above.

If someone else has used your saw and gone into "pry bar mode" .... same as above.

Check the clutch cover for cracks and gouges.
Can't remember if these oil straight through but if so can cause similar problem as,,,, well, you guessed it .... same as above.

 

[Homelite]

Make sure your bar studs are driven in tight and haven't loosened up over time. If they back out they can hold the bar away from the frame enough to prevent a correct seal and leak.

Make sure your bar matches the bar stud style. If its held out .... same as above.

If someone else has used your saw and gone into "pry bar mode" .... same as above.

Check the clutch cover for cracks and gouges.
Can't remember if these oil straight through but if so can cause similar problem as,,,, well, you guessed it .... same as above.

I've checked that everything is clean, straight, and tight, but still having issues. I think there might be something to the worn worm gear for the oiler. If it is worn or the seals are starting to go, it would dump a lot more oil than it should.

The saw definitely has a lot of hours on it, but I keep the chains sharp and I rarely max out the bar in the log when milling. It would be nice to have a larger saw, but it is a good compromise for weight and power. It has done well and I'm not in a production scenario, so a couple hundred BF a year is about all I do. I also use the saw to fell and buck, so having to haul around a larger saw at times would be a bit more trouble. I would like to get a 660 or 880, but for the price, I could get a low end bandsaw mill.

BTW, what sort of compression should the saw have? I'm not sure, but now I'm curious how much it might have dropped since new.

 

[stihl for life]

140-150

 

[Homelite]

I did some investigating this weekend with my dad's saw (same model, older style) and discovered the same issues with his. Tried a Stihl bar (currently running an Oregon Power Plus) with different chains and no problems. I went to the local Stihl dealer in town and picked up a 24" Stihl bar. When I compared the used Oregon to the new Stihl, I discovered that the Oregon had so much wear at the crest of the bar (1/4" top and bottom), that when I tensioned the chain it must have pushed the oil galley hole on the bar past the oiler on the saw, creating the issue I had been experiencing. Once I put on the new bar and chain, no issues I could see. I will be trying to mill this weekend to see if all is well. The old bar had 8 years of heavy use, so I guess no wonder it had some wear...just had no idea that much.

BTW, for as many hours as that saw has, I did a compression check this weekend and came up with an average of 142 psi of compression. I guess it pays to maintain your saw. I run a little heavier on the oil, closer to a 40:1 mix and clean the fuel and air filters 1-2x a year depending on the saw use. I also change out the plug at least once a year and check it for buildup pretty regularly. I was cutting some 36" cherry butt logs this weekend and it didn't skip a beat.

 

[anlrolfe]

I was cutting some 36" cherry butt logs this weekend and it didn't skip a beat.

Some here will tell you that an 039/390 doesn't have enough ballast in its breaches to do that.... I know better.

 

[Wood Doctor]

Is it possible that the small oil holes on the bar do not line up with the the oiler slot on the saw's housing? I ran into this with an MS 290. Take a look at my discovery:

This was a bad production run with the 290 and was fixed later by Stihl. The slot was positioned too low. I used a chisel to carefully widen the slot on the case so that it surrounded the oil hole. After that modification, the oiler worked.