026 PRO Identification Issue

[SteveSr]

Just went through some of the same issues when I changed carbs on my 026 pro. The filter cover needs a filter with a little plastic nose. That only comes for the 2 screw carb with compensation port. The filter you have is for the screw on filter cover (Older) and no compensating port. I put the 3 screw carb (wt194) on and it needs the filter without the compensating port. Unfortunately that filter doesn’t have the plastic nose needed to hold the filter cover on.
the easy fix was to use the compensating hole filter so the filter cover fits and make a plug to block off the compensating port. Was a 5 min job on my lathe. i can post pictures if you need them.

This brings up another issue for the OP... Did someone put the compensating cover on his old carb. Can't see from the photos. Don't you just love working on a Frankensaw!

 

[SteveSr]

View attachment 899882

That serial number doesn't match the much older tank assembly either.

 

[SteveSr]

Must be interesting (maybe even exciting!) trying to run that saw without a tank vent. turn the saw sideways and watch gas go everywhere.

 

[HarleyT]

That serial number doesn't match the much older tank assembly either.

That is what Stihl's database says. Back when they were switching over to the MS designation, there was a lot of overlap, and mutants were out there. as far as running the serial number, that is what they say. It could have an older fuel tank slapped on, who can say?

 

[HarleyT]

But looking closer at the pics, it looks like the top and air filter cover are likely from a newer saw. So their emblems/tattoos are deceiving....

 

[RicknTroyNY]

Does anybody disagree with my thinking... namely... pick up the narrow filter and have every expectation that a round knob cover will fit? Really hoping that you guys all think that will work... lol

 

[RicknTroyNY]

Also... would anyone like a different angle picture. Embarassed to say tank vent was on bench...it came off as i wrestled with wrong filter.

 

[SteveSr]

Also... would anyone like a different angle picture. Embarassed to say tank vent was on bench...it came off as i wrestled with wrong filter.

Need a photo of the bottom of the saw, crankcase. Need a photo of the existing carb and the model number off of the side. Should be a WT-xxx. Does the cylinder have the compression release or the machining area for one on the top of the cylinder. Photo needed.

Beginning to think that someone put an old incompatible tank assembly on a newer saw crankcase. The path of least resistance may be to buy a newer used tank assembly and resell the one that you have.

Since the saw has a running problem and while you are taking photos pull the muffler cover and take photos of the piston.

 

[Mad Professor]

just change the plate on the new carb with the old one

What he said ^

The adjustable carb w/compensator is the WT-426

 

[RicknTroyNY]

This evening!!

 

[mbrick]

How does the air filter mashup relate to it not starting / running correctly? Of course it will be nice to get the right parts on there but the old flocked filter looks "ok" that it would run.

 

[RicknTroyNY]

Carb is gonna be a minute

 

[RicknTroyNY]

Cylinder

 

[RicknTroyNY]

Im not ready to tear it down so I can excavate that carb #. If a filter and rear cover get it back in business i will be happy. It was VERY hard to start. I only got it going after cleaning the plug and giving her a bit of ether. The forum GENERALLY seems to suggest that the carb may be sucking in to much air to have enough left to pull the gas from the tank. Or the carb may not be closing 100%... most of the stories seem to be guys replacing everything and not getting satisfaction. Once it starts... it cuts great and i adjusted the idle down perfectly.

 

[RicknTroyNY]

How does the air filter mashup relate to it not starting / running correctly? Of course it will be nice to get the right parts on there but the old flocked filter looks "ok" that it would run.

The back of the filter was rubbed/wore right through. Shot. During operation the cover was always coming off

 

[RicknTroyNY]

That filter really doesnt want to seat firmly...

 

[SteveSr]

Carb is gonna be a minute

Piston shows damage perhaps from ingesting something through the hole in the air filter. Also the top end looks to be "newish" like someone might have installed an AM piston and cylinder kit.

The crankcase shows the "pro" oil adjustment hole on the bottom. Is there a slotted quarter turn adjustment in the bottom of the hole? If so, then you have the pro oiler piece. If not it was a regular 026 non-pro.

 

[SteveSr]

Im not ready to tear it down so I can excavate that carb #. If a filter and rear cover get it back in business i will be happy. It was VERY hard to start. I only got it going after cleaning the plug and giving her a bit of ether. The forum GENERALLY seems to suggest that the carb may be sucking in to much air to have enough left to pull the gas from the tank. Or the carb may not be closing 100%... most of the stories seem to be guys replacing everything and not getting satisfaction. Once it starts... it cuts great and i adjusted the idle down perfectly.

That is the wrong carb for that saw. It never came with the enclosed/recessed adjustment screws. Also note that the builder had to hog out the plastic air box to jam it in there.

 

[RicknTroyNY]

Piston shows damage perhaps from ingesting something through the hole in the air filter. Also the top end looks to be "newish" like someone might have installed an AM piston and cylinder kit.

The crankcase shows the "pro" oil adjustment hole on the bottom. Is there a slotted quarter turn adjustment in the bottom of the hole? If so, then you have the pro oiler piece. If not it was a regular 026 non-pro.

 

[SteveSr]

Sorry, you have a real mess of mismatched Stihl and possibly AM parts. the CL seller is dishonest and a bad excuse for a mechanic. He knew that he was selling a problem and did it anyway. If it was at one time really a "pro" you would need to replace the tank assembly and the carb at a minimum to bring it back to where it once was. But then I seriously question the condition of the existing cylinder and damaged piston.