Is this hole supposed to be there? Stihl 038

Ok I've been dealing with leaking b/c oil long enough. With the warmer temps, my saw has a steady drip coming from the clutch area. I emptied the tank earlier in the week and blew out the vent. Cleaned the saw real good. Filled it 1/2 way. Check it this evening. Tank empty, bar oil on shelf and garage floor

Disassemble the saw to the gear drive and find this:

Oil squirts out of that hole when driven by the clutch, spraying everything in the vicinity in bar oil (clutch, brake, etc.) I don't think that hole is supposed to be there. It looks blown out, not drilled. It's causing the bottom of the clutch cover to literally fill with oil and creating quite a mess.
Can someone verify this for me? I'll stop by the Stihl shop tomorrow.

I don't believe so. Clean it real well, sand it, and put a dab of JBWeld on it.

If it seems to be pissing bar oil all over the place, and it's not part of the delivery system to the chain then plug it up. I would take a look at a parts breakdown first, just to make sure you aren't missing something.

I have a 038 tore down right now. I'll look at it and see if mine has a hole in it.

Air Bleed Hole

I thought it was for an air bleed hole, so you could get the gear down on the shaft w/o hydro oil locking up on the shaft end.

Stihl 032, 045 & 056 saws have the hole in gear, but they also have a shaft seal on the pump body & a fiber spacer washer over the shaft down inside the bore. I have seen this shaft seal missing/wobbling out on some failed pumps leak...

Your oil pump piston and/or body is worn. There should not be any oil at the bottom of that gear cavity. The oil is pumped on the other end of the piston. If it is getting down to the gear and shooting out, there is another problem with the pump.

hotshot said:

I thought it was for an air bleed hole, so you could get the gear down on the shaft w/o hydro oil locking up on the shaft end.

Stihl 032, 045 & 056 saws have the hole in gear, but they also have a shaft seal on the pump body & a fiber spacer washer over the shaft down inside the bore. I have seen this shaft seal missing/wobbling out on some failed pumps leak...

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Mine has the shaft seal where this gear slides into the pump.

Saw Dr. said:

Your oil pump piston and/or body is worn. There should not be any oil at the bottom of that gear cavity. The oil is pumped on the other end of the piston. If it is getting down to the gear and shooting out, there is another problem with the pump.

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Yeah I'm definitely getting oil on the drive side of the pump. Where the worm gear meshes with the pump has a puddle of oil in it. How much is an oil pump from Stihl? Are they still available for the 038?

I bought the saw used (obviously) and with the oil issues, I'm going to guess that someone ran it out of bar oil at some point.

I don't think the hole is supposed to be there.

There is a seal that fits behind the drive gear in the pump body , there is also a plug that fits in the end of the pump body behind the piston, check those too.

Also two o-rings to worry about

Mad Professor said:

I don't think the hole is supposed to be there.

There is a seal that fits behind the drive gear in the pump body , there is also a plug that fits in the end of the pump body behind the piston, check those too.

Also two o-rings to worry about

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The seal in the pump body, the one that the drive gear slides through, is good. Nice and clean, no nicks or tears.

What two o-rings?

Knuckles said:

The seal in the pump body, the one that the drive gear slides through, is good. Nice and clean, no nicks or tears.

What two o-rings?

Click to expand...

Quick response, at least one is for the flow adjuster that comes up from the bottom.

Ok after 2 months I'm getting around to fixing this oil leak. However, the dealer wants $100 for a new pump and he can't verify for me whether that is my problem. He claims that either the pump works or it doesn't. He's never seen one leak like this.
The saw no longer oils the b/c. With the saw running, bar oil literally pours out the bottom. Right where the clutch cover meets the cases.
The following pics were taken today. The 1st shows oil coming out of that small hole in the gear. (dealer says new gears come with that hole) The 2nd, shows where the pump mounts to the saw. That area was filled with bar oil. (pic was taken after I cleaned it out)
I don't want to drop $$$ on a pump if that's not the problem.



Yes, I've cleaned out the vent. Yes, I've checked for cracks & found none. Yes, I've checked oil hose.
I'm hoping someone here has seen this too.

1) hole in gear should be there to assist fitting
2) check gasket between pump and sawbody for tares
3) check seal around drive on the pump (bit gear goes onto ) reverse screw it and it should come out to expose the seal
4)AFAIK there is an O`ring sealing the pump shaft which may also be your problem

really thats all there is to go wrong barring cracks which you`ve already eliminated

4)AFAIK there is an O`ring sealing the pump shaft which may also be your problem

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The bar oil pours out of that small hole, but nobody can tell me if that's normal.
What about this o-ring? I've looked over all the external seals, including the drive gear seal, everything checks out.

Had an "ah-ha" moment this evening and discovered that you can disassemble the entire pump. Found the two o-rings everybody keeps talking about. Popped out the black plug and pulled the piston out of the body......which only left me scratching my head.

The o-rings were/are in good shape. No visible tears. No nicks on the mounting surface.

The pump piston didn't look worn either. No visible wear marks on it.

I cleaned the pump with a bit of de-greaser and everything went back together real nice. There was nothing that jumped out and said "hey look at me, this is the problem"
This thing leaks oil through that gear so bad that it doesn't pump oil up to the bar anymore. And I'm told that a new gear will have a hole in the center also.

Tell me no one on here has ever seen this on an older Stihl??

Saw is currently sitting in pieces on my work bench. No sense I put it back together if the oiler doesn't work.
Obviously it needs a new pump, but someone said that those pumps either work or they don't. They won't just start puking oil one day.

Just getting a little frustrated.

Knuckles said:

The bar oil pours out of that small hole, but nobody can tell me if that's normal.

Click to expand...

I feel bad that no one can answer your questions. No 038 experience here, so I'm no use.

If Lakeside were still here...........

Hi Knuckles,
If you want a copy of the service manual, send me a private message with your email address and I will forward a copy to you.

Best wishes,
Bob

Hello knuckles,

I have the same problem as you with my 038 magnum.



There is a hole on my gear too.

Do you think that the seal n° 3 on this picture who need to be replace ??



Have you solved the problem ?

Enough Already

You cannot just look at O-rings or look at seals and pass them off as fine.

Pressure test the pump at 4-5 psig (plug the discharge & inlet ports plus install the black end plug) while holding the drive gear down with your thumb, and you will find a large air leak somewhere. This is the low pressure side of the pump, and unless your internal pump discharge port communicating up the bar guide face is plugged, there will normally be very little to no oil in this side, and your gear face hole will not seep. The discharge port is the top hole in the pump if I remember correctly. No need to epoxy the gear face hole up.

An unconventional fix would be to add an O-ring & additional washer over the oil pump shaft after the spring & washer is installed over the shaft, but this decreases your stroke length & thus pumped volume. If the soft aluminum bore is worn out, then heed the Saw Dr.s advise & replace the pump body with a new one.

These same 1117-640-3001 pumps have been running on over five series of saws for over 30 years with great results.

Shop manual recommends replacing parts 3 , 10, and 13 (on the above parts IPL) the sealing ring and o-rings, respectively , when servicing the pump.

If it still blows oil with a sound gasket there is a problem with the bore of the pump body and/or the pump piston.

Also check the surface of the pump dive gear where it contacts the sealing ring

Hi i just replaced the oil pump on my 038 and it solved the problem. It was oiling some but not what it should.hope this helps bought mine at baileys for around 65.00 dave