New (to me)Stihl 026 pro wont stay running

[9050LX]

I just bought a stihl 026 pro that looks pristine.The guy I bought it from claims he got it from his boss who used it once and put it aside for a couple of years,then gave it to him.The piston exhaust and intake sides look like new.The carb is an adjustible Walbro.I tried to adjust from one turn out,but it will not stay running and seems to load up with fuel.It seems to run good from 1/2 to full throttle but when throttling down dies out.The compression is only 130 lbs which seems a little low.The carb is clean.The impulse line seems like not a very firm connection where it goes into the carb.could this be the culprit?I paid 100 dollars and knew it had issues when I bought it.Beauty of a saw though,Guess I will be happier when I figure it out.

 

[sefh3]

Well let's see. Pull the muffler and check the piston. If the compression is low then the rings might be toasted. If they look good. Replace the fuel filter and order a carb kit. If the saw has sat with fuel in it will eat the carb gaskets.

 

[9050LX]

I checked the piston from intake and exhaust and it looks like a new one.The carb was rebuilt by the previous owner.I took the carb apart and it looked ok but I dont know for sure.I am suspecting the impulse line as it goes into the carb as it doesnt feel very much like a secure leakproof seal.

 

[DSS]

I had an 026 wouldn't tune right, lean, rich, hard start....

It was the walbro carb, replaced the carb and it runs like a dream. Apparently some of those were bad from the factory. No amount of kits will fix them.

 

[nmurph]

Check that the diaphragms and gaskets are in the right order. The is an easy mistake for the rookie carb rebuilder.

 

[sefh3]

Make sure on the diaphram side it goes carb, gasket, diaphram, then cover. Also make sure your metering lever is flush with the carb body. Also pull the needles out and shot some carb cleaner down them and assure they are clean.

 

[lone wolf]

Dont buy a new one yet but it sounds like the carb is bad to me.Check your vac/pressure first.

 

[Showme]

Check that the diaphragms and gaskets are in the right order. The is an easy mistake for the rookie carb rebuilder.

Exactly, I bought a 028S that wouldn't run right at WOT. Rebuilt the carb and it's fine. The seller didn't bother to tell me that he had tried to rebuild the carb. He left a diaphragm out and if another member hadn't of sent me a IPL for the carb I doubt I'd have figured it out.

 

[9050LX]

Anyone know where I can get an exploded view of a Walbro?

 

[lone wolf]

Anyone know where I can get an exploded view of a Walbro?

Welcome to walbro.com try to see what model you have then look it up

 

[9050LX]

I found the exploded view but the pic is not very clear for 50 year old eyes........

 

[9050LX]

Well I got it running.Amazing how good it runs when the fuel pump diaphragm is installed!Previous owner must have forgot or something.Still occasionally runs lean off of idle(builds rpms) when tilting saw.Could this be a cracked fuel line? By the way,This saw with an 18 inch bar is slightly more powerful than my 024 super with a 16 inch bar to my calculation.

 

[sefh3]

It could be a crack in the fuel line but more than likely a seal has gone bad. Vac/Pressure test the same and see what happens. In my signature line is a link to build a cheap tester.

 

[PogoInTheWoods]

I had an 026 wouldn't tune right, lean, rich, hard start....

It was the walbro carb, replaced the carb and it runs like a dream. Apparently some of those were bad from the factory. No amount of kits will fix them.

Wouldn't happen to remember which model Walbro, would ya? Both my 026's have WT-22's on em and both are a little finicky to tune.

Poge

 

[DSS]

Wouldn't happen to remember which model Walbro, would ya? Both my 026's have WT-22's on em and both are a little finicky to tune.

Poge

This was a WT 194. Gave me fits for awhile, I tell ya.

 

[JustinM]

As others have said, you're most likely looking at fuel delivery - be it fuel line, fuel filter or the carburetor itself.

Especially when you mention in your OP that it was "used once and put it aside for a couple of years." My guess is that it was put aside with gas mix left in it, which almost certainly means rubber being eaten away. Id start with the easiest (cheapest) fix (fuel line & filter) and work my way back from there.

It is entirely possible that the carb itself needs replacing, but its also not hard to believe that it would just be the lines & the gaskets.

Good luck, it will be well worth the effort once you figure it out.

 

[9050LX]

Where is a good place to buy a Walbro 194 who just may have in stock?

 

[9050LX]

Anyone ever order from Northwood Saw? They have A Zama carburetor for 40 dollars.

 

[DSS]

Anyone ever order from Northwood Saw? They have A Zama carburetor for 40 dollars.

Northwood is a great place to order from, but I don't know if that zama is a direct replacement for a walbro. Somebody can probably tell you.

Ebay may be the cheapest bet for a walbro.

 

[ttyR2]

New WT-194's are listed on ebay all the time. I replaced the stock carb on my 026 Pro with one. Runs awesome.