Stihl 034 issue

Arborist Forum

Help Support Arborist Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
Removing and installing a pto seal isn’t that difficult. However, you may have more problems if you have oil in the crankcase/cylinder. That would require a case split to properly fix. I would replace the bearings and seals during assembly.

You could get a higher quality top end as well and have a heck of a saw. $$$, though, and a lot of learning along the way.

Well I have 8 or 9 saws. I have been lucky to buy saws for cheap and do quick fixes to have good running saws (eg. carb, lines, boots, coil, brakes etc.) But this one is full of problems and a money pit. Already changed lines, boots, rebuild carb, AM P&C, but she keeps getting problems Im gonna give up on this one I think lol
 
Why would the modified screwdriver wouldnt work to replace the seal on this side ? Maybe a stupid question but i have never replace seals on a saw
Thx
EF5426BA-3676-4773-839D-06017BB085F8.jpeg
 
No sense in putting in a seal now if you may have to split the case. New seals come with a gasket kit.

Are you 100% sure the mix does not have 2-3X too much oil?

If you had a pres/vac tester you could check the oil tank and the motor for leaks.
 
No sense in putting in a seal now if you may have to split the case. New seals come with a gasket kit.

Are you 100% sure the mix does not have 2-3X too much oil?

If you had a pres/vac tester you could check the oil tank and the motor for leaks.

Well I dont have a case splitter but I have the seal on hand. Fuel mix was ok. I can clearly see the red color of my bar oil in the cylinder. Piston is perfect though.
Since I dont have a case splitter and I wont split it, i thought about replacing seal, so if oil was filling case by the seal the problem would be solve. She was a runner but smoke as crazy at startup until oil is burned. But I had to replace recoil spring and rope but after that i cant pull as if piston was stuck. This is the reason I started to strip it again
4883ECDB-F3F5-4DBE-807C-BA2D00F899D8.jpeg
 
The saw is locked up or the recoil you just worked on? The knot may need to be pushed back so things engage correctly. Can the flywheel be turned by hand?

If the saw has a failed case gasket and you have a lot of oil in the cylinder, it may feel locked up.

If you don’t feel like messing with it, I get it. OEM prices on bearings, seals, etc. are high. It takes me a fair amount of time to do a full rebuild... lots of cleaning and waiting for certain parts to come in.
 
The saw is locked up or the recoil you just worked on? The knot may need to be pushed back so things engage correctly. Can the flywheel be turned by hand?

If the saw has a failed case gasket and you have a lot of oil in the cylinder, it may feel locked up.

If you don’t feel like messing with it, I get it. OEM prices on bearings, seals, etc. are high. It takes me a fair amount of time to do a full rebuild... lots of cleaning and waiting for certain parts to come in.

Recoil work ok when not on the flywheel (rope get out and rewind correctly. Flywheel turn by hand on both direction. When install on the flywheel, sometime the rope wont go out at all, and sometime flywheel seems to make a turn and then get stuck. If im right, recoil spring cant be put in reverse, so maybe this is oil in the cylinder, when piston goes up, I see oil moving around on too. Really dont know where the leak could be
 
Well I dont have a case splitter but I have the seal on hand. Fuel mix was ok. I can clearly see the red color of my bar oil in the cylinder. Piston is perfect though.
Since I dont have a case splitter and I wont split it, i thought about replacing seal, so if oil was filling case by the seal the problem would be solve. She was a runner but smoke as crazy at startup until oil is burned. But I had to replace recoil spring and rope but after that i cant pull as if piston was stuck. This is the reason I started to strip it again
View attachment 751177


The crankshaft seals seal the crank area of the crankcase. They have nothing to do with the oil tank.

If you are getting bar oil in the crank part of crankcase it is a bad gasket, or a crack in the case. You did mention that the case screws (5) were all tight.

Has the saw ever been dropped or had a tree fall on it? Something that could have damaged the case
 
The crankshaft seals seal the crank area of the crankcase. They have nothing to do with the oil tank.

If you are getting bar oil in the crank part of crankcase it is a bad gasket, or a crack in the case. You did mention that the case screws (5) were all tight.

Has the saw ever been dropped or had a tree fall on it? Something that could have damaged the case

But what if the oil delivery hose is leaking and my seal is not tight ? Oil pouring out of the oiler cannot makes it way into crankcase by the seal ? Maybe stupid hypothesis but im not a expert at all. I just change seal anyway, i had it on hands and clutch, oiler and everything was already removed.

I bought the saw used, so I dont know if she had been drop or anything. How can I know where the leak is ?

Is there a way to flush the oil in the crankcase without splitting it and without removing seals?
Thanks
 
But what if the oil delivery hose is leaking and my seal is not tight ? Oil pouring out of the oiler cannot makes it way into crankcase by the seal ? Maybe stupid hypothesis but im not a expert at all. I just change seal anyway, i had it on hands and clutch, oiler and everything was already removed.

I bought the saw used, so I dont know if she had been drop or anything. How can I know where the leak is ?

Is there a way to flush the oil in the crankcase without splitting it and without removing seals?
Thanks

Oil hose leak at oil pump, is going to pizz out oil on the floor when saw is not even running if tank has has enough oil in it.
 
Your theory is physically possible, but realistically unlikely. When you end up splitting the case to find the source of the bar oil leak you'll be buying another seal. Luckily a whole set of seals and gaskets for 1125s is less than $15 at the Stihler
 
The crankshaft seals seal the crank area of the crankcase. They have nothing to do with the oil tank.

If you are getting bar oil in the crank part of crankcase it is a bad gasket, or a crack in the case. You did mention that the case screws (5) were all tight.

Has the saw ever been dropped or had a tree fall on it? Something that could have damaged the case

Is the 5 screws for the crankcase those on this picture ? Im not sure about the 2 in red, which seems to screw "on itself", they wont stop turning. May this be the problem ?

Thanks !

IMG_2777.jpg
 
You'll have to forgive me, it's been a minute since I split an 1125 case. There is usually one out at the end under the muffler. Maybe one more hiding under that cover, or aft of the clutch area?
 
For your sake I hope so, but more than likely you have a gasket compromised between those two bolts on either end of the wall between the oil tank and crank case.
 
You need to take the cover that covers the chain brake and clutch housing off. And the metal chain guard. As shown in previous post they are towards front of saw

If the screws that hold the cover on spin and don't tighten, the threads are stripped.

When you have the cover off you can clean out all the crap that's built up over the years.

If the P/C is on you can remove the clutch (reverse threads, need a piston stop), to inspect oil pump and/or do pres/vac test as seal will be exposed if you also take out bolts in oil pump. Don't try to take the oil pump hose off, or you will be buying a new hose and they are a PITA to install.
 
Back
Top