*Stihl 026 oil pump question

[anderson3754]

I have this peculiar oil leak on this 026. If you run the saw off and on for a few hours there is always a large puddle of bar oil under the saw later in the day.

Well I found this leak last week, after taking the bar and chain shield off cleaning everything spotless. It's coming from the line that oils the chain. I filled the oil tank ran it for a few minutes and watched it drip for three days. Wipe everything clean again, come back and look a few hours later, and you can see the oil oozing out of the oil tube, running down the side of the saw leaving a puddle. Wipe everything clean come back and the same thing. This went on for 3 days till the oil tank got down below the half way point.

Anyone have any clues how this could be happening if the pump is not rotating there should not be any oil coming out of the oil tube.
My thought.... it is like siphoning gas from a tank once you get it started you can basically empty tank.

Is there a check ball or a pressure valve inside the oil pump to stop this once the motor is shut off ?

Thanks

 

[a. palmer jr.]

Generally heat will force some oil out for a short while, till it cools off. It sounds like yours does siphon some oil out until it gets past the vent. I guess you've tried turning the saw on it's side and temporarily taking the oil cap off, relieving the pressure in the tank...I believe the saw has a small vent under the bar plate toward the front, you might check to see if it's stopped up..other than that I'm not sure.

 

[anderson3754]

Okay thanks I'll try turning it on it's side and cracking the oil cap open / off and see if that changes anything. This vent you speak of, is it easy to replace ?

Regards

 

[fl cracker]

Its either the vent or case gasket leaking i had a 044 do that and i couldnt figure were leak was drove me crazy it was gasket. Had to split case and replace gasket

 

[a. palmer jr.]

Okay thanks I'll try turning it on it's side and cracking the oil cap open / off and see if that changes anything. This vent you speak of, is it easy to replace ?

Regards

The vent is just a cylinder shaped silver colored thing with a small hole in it. I believe you can just poke it into the oil tank and remove it from the tank. The new one just pushes in from the outside. May have to be tapped into the block with a small hammer and a drift. Not real sure that's your problem but if it is it is easy to change.

 

[anderson3754]

Great thanks for this info. Will be calling my Stihl Dealer this morning to see if a vent is in stock.

Regards

The vent is just a cylinder shaped silver colored thing with a small hole in it. I believe you can just poke it into the oil tank and remove it from the tank. The new one just pushes in from the outside. May have to be tapped into the block with a small hammer and a drift. Not real sure that's your problem but if it is it is easy to change.

 

[a. palmer jr.]

Great thanks for this info. Will be calling my Stihl Dealer this morning to see if a vent is in stock.

Regards

Is your vent bad? You should be able to test it first. Basically it's just a little hole for the oil tank to breathe through.

 

[anderson3754]

Okay I'm back. Went to my local Stihl Dealer yesterday afternoon and bought a new oil tank vent and installed it. Started the saw up and cut wood for a 1/2 hr, shut it down and took it apart back in the garage. After installing the new vent and running the saw for about minutes shut it off and set back down on the benchnand watch weep oil for about 10 minutes and basically stop. It produced a small puddle approx 3 inches diameter, which I consider normal, on observations of my other Stihl saws.

Why it took 10 minutes to stop weeping makes no sense to me, but at least now it's not pushing out a half tank of oil which is a crazy mess to clean up.

Regards

 

[a. palmer jr.]

I would have to say it's because of the heat in the oil tank, expanding the oil and pushing it out at the vent. That's why I usually just open the cap a bit to let the pressure out..

 

[anderson3754]

I would have to say it's because of the heat in the oil tank, expanding the oil and pushing it out at the vent. That's why I usually just open the cap a bit to let the pressure out..

I think your right about the heat expansion to some extent. But mine was actually draining half the tank out via the oiler tube, not the vent. This would take place over 3-5 days. After putting in a new vent it now just leaves a puddle that I consider normal based on what my other Stihl's puddle after sitting few days or weeks. The new vent definitely made a difference. It was a cheap easy fix, took a brass punch gently knocked the vent into the tank, pulled it out with a magnet, then installed the new one. The vent was like $3.12 out the door.

Today I went and looked at it after sitting for a few days the puddle is as expected for most, if not all saws.

Regards

 

[a. palmer jr.]

I usually just drain the gas and oil if the saw's gonna sit for very long..