I rebuilt this 026 that had a scored piston, more or less just for the learning experience and fun. I replaced the piston, rings, cylinder, main bearings, and seals and gasket. I got it all back together the other day, and it has 145psi of compression, and it has spark. It won't run unless I drop a bit of fuel down the sparkplug hole. It will run on that and then quit. I took the carb apart, the gaskets looked good, and it wasn't all that dirty. I cleaned it up and put it back on, still nothing. I then blocked off the intake and exhaust ports and made an adapter on the intake block off plate to connect my vacuum and pressure tester. There was a very very slight leak of pressure when I pumped it up to about 7psi, it was a slow leak. I sprayed soapy water around the main seals and the head gasket and found no evidence of a leak. When I installed the two main seals originally, I put a thin film of RTV silicone on them and was pretty careful driving them in so I'm pretty confident they're sealed. I didnt notice and leaks coming from the impulse line hose either. Any thoughts on any of this? How bad would the saw have to leak from the crankcase for it to not pull fuel? Would even the slightest pressure and vacuum leak cause this?
Rebuilt Stihl 026 isn't getting fuel...
- Thread starter Jhats79
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old-cat
Fir Man
Is the impulse line plugged?
Revisit the carb.
OtisHertz
ArboristSite Lurker
Stihl not pulling gas
After carb cleaning, carb rebuild, then carb replacement, new fuel line and intake filter, good compression, My 14 year-old 026 would only run on
choke, would rev for 2 seconds then die off choke. DOH! It's so obvious NOW after it got replaced: the crankcase vacuum nipple was cracked.
Ran for years with a "small" crack- always started on the 15th pull unless it was just shut off. Got worse and worse, finally needing to rev to the max and could barely cut wood, then it wouldn't run at all. When it was new I could leave it idling for many minutes, never stalled, it would start with a half-pull when warm, 2-3 pulls when cold. The new carb's vacuum line barb pushed that nipple sideways enough to open the crack. I tested the bugger and there was no vacuum leak. Eventually I gave up and the repair guy charged me $37 and said it's fairly common with this
saw. Runs like a top, like brand-new. Starts on pull #3 at 15 degrees after 2 weeks idle. Glad to have my best workhorse back online.
Good to know
After carb cleaning, carb rebuild, then carb replacement, new fuel line and intake filter, good compression, My 14 year-old 026 would only run on
choke, would rev for 2 seconds then die off choke. DOH! It's so obvious NOW after it got replaced: the crankcase vacuum nipple was cracked.
Ran for years with a "small" crack- always started on the 15th pull unless it was just shut off. Got worse and worse, finally needing to rev to the max and could barely cut wood, then it wouldn't run at all. When it was new I could leave it idling for many minutes, never stalled, it would start with a half-pull when warm, 2-3 pulls when cold. The new carb's vacuum line barb pushed that nipple sideways enough to open the crack. I tested the bugger and there was no vacuum leak. Eventually I gave up and the repair guy charged me $37 and said it's fairly common with this
saw. Runs like a top, like brand-new. Starts on pull #3 at 15 degrees after 2 weeks idle. Glad to have my best workhorse back online.
Good to know
cedarshark
Addicted to ArboristSite
You did not mention replacing your fuel line ,impulse line and filter. The last 026 I repaired had a "glaze" from dried fuel on the filter that completely shut it off. It does not appear you have a vacumn leak. It is not necessary to add fuel thru your spark plug hole. You can spray it directly in your carb. I would vac test both fuel and impulse lines to see if they collapse, clean(or replace)your filter then rebuild the carb in that order. Sometimes the diaphram in the carb will get dry and stiff from age and will not pump fuel.
