Stihl 029 Super Oiling Problem

[JamieR]

I have a Stihl 029 that’s not oiling when the bar is on. I’ve taken the bar off and it pumps oil fine. The pump it turned all the way open. The saw was rebuilt about 6 months ago. Also has new oil pump, work gear, oil line, oil filter, clutch, bearing, and clutch drum. I just bought a new Stihl bar and chain, but still the same issue.

 

[HarleyT]

Put up a pic or two, of the saw, and the bar where it mates with the saw.

 

[JamieR]

 

[a. palmer jr.]

You might check and make sure the bar hole isn't filled with paint, it looks like it's fairly new.

 

[JamieR]

It’s clear, but it stop oiling on the old bar. I don’t know how mounting the bar would cause it to stop pumping oil.

 

[HarleyT]

Take a pic of the studs at a better angle, seeing the marks on the bar, and the look at the studs, the bar may not be meshed with the saw tight enough to seal.

 

[JamieR]

Yea, the back stud sticks out a tad, but it’s seated as far back as it will go.
But there’s no oil running down behind the bar, so it doesn’t pump at all.

 

[HarleyT]

Run it some with the bar/chain off, and put up a pic of the flow/if any.

 

[JamieR]

This is about 10 secs after startup at idle.

 

[JamieR]

Here’s about 15 more seconds of idle time.

 

[a. palmer jr.]

Is the oil going down between the bar and the saw?

 

[Kenskip1]

This could be a long shot but could you be running a 325 chain on a 3/8 bar? If so the 325 drivers will not collect and distribute it to the bar and chain. The stihl bar is .063 weather you are using a 325 or 3/8.
Something else, could you be using a .058 gauge chain in the .063 bar? I do not mean to insult you however if this could be the case then the .058 chain will not pick up and distribute the oil. Worn drivers could be another possibility.

 

[AoxoMoxoA]

As HarleyT suggested, the rear bar stud is definitely protruding out farther than it should. The indent on the bar itself (highlighted in attached pic) illustrates that. If it's being held outward, the bar cant seal flush against the oil channel, thus oil would just drip behind the bar.

It also appears the bar stud shoulder overlaps the tension screw adjuster (second highlighted photo), which is probably why it's not seating in far enough.

 

[Captain Bruce]

Yea, the back stud sticks out a tad, but it’s seated as far back as it will go.
But there’s no oil running down behind the bar, so it doesn’t pump at all.

Its the wrong stud, AND, a .325 chain won't even move, on a 3/8" bar. It would bind up while mounting the bar.

 

[JamieR]

Is the oil going down between the bar and the saw?

No it doesn’t. The saw doesn’t pump at all with the bar and chain on.

 

[JamieR]

Yes, the rear stud does stick out, but it’s fully seated into the saw. I removed both studs to see if they needed to be swapped but they are different lengths and threads, so they are in the correct orientation.
Also, I checked the tension screw adjuster and the plastic has an indentation to fit around the shoulder of the stud.
I just now thought of mounting just the bar to see if the oil pumps through it and it does, so I think it has something to do with the clutch drum.

 

[ZeroJunk]

Mill about 1/8 off of the rear stud where it goes in the saw. That one actually screws in to the crankcase itself.
If they used an aftermarket motor when they rebuilt it chances are the manufacturer didn't drill and tap it deep enough. Ideally , screw an 8 MM dies on it so that it will fix the threads when you take it off.


BTW, the bar being on or off the saw has nothing to do with the oil pump. Unless, it won't let the clutch drum turn somehow.

 

[pioneerguy600]

Mount the bar and check to see if the tail end of the bar is contacting the clutch drum. Does the 029 take the 30 or 50 bar?

 

[HarleyT]

I have noticed with saws like these, when they get old and well worn, that the plastic cases will shrink and distort. I had an old 025 that had "shrunk" so much, that the engine was loose, and I ended up having to mill the 4 metal bushings to make the engine fit tight.

 

[pioneerguy600]

I have noticed with saws like these, when they get old and well worn, that the plastic cases will shrink and distort. I had an old 025 that had "shrunk" so much, that the engine was loose, and I ended up having to mill the 4 metal bushings to make the engine fit tight.

I have also seen the bar mount pad warp or bow upward near the stud center so much that the bar would not seal down tight, the oil just drooled down behind the bar and pad. The OP is saying the oil will come out the oil slot with the bar off but not when the bar is mounted, that is why I asked to see the bar mounted to see if the bar tail end is contacting the clutch, stopping it from turning.