Stihl 029 Won't Start

[KE4AVB]

Okay Guys here is one you to figure out. I done found the problem just want if any of you can think why it was not starting.

1. Carburetor is known to need rebuilding so that is a give me.
2. Priming via carburetor or direct ends in no start or even a hit.
3. Spark arrester clean.
4. Flywheel timing is correct.
5. Has 120 psi compression.
6. Has good spark and new known good plug.

[Luffydog]

Compression relaease bad maybe. I don't work on to many 2's anymore

[KE4AVB]

No compression release but on the right track.

[Luffydog]

Stuck ring

[KE4AVB]

I would say so. When I pulled the muffler severe upper cylinder and piston damage. Appears to have been straight gassed. It is the first time I had a very good compression reading from one that has this much damage. It is lost compression right at the top of the compression stroke before the plug fires.This saw must of had a compression at one time of 170+ psi. Usually with my compression gauge if the 2C has 100+psi compression it at least hit and most with 120 psi are very good used saws.

Just one of the very rare cases where a compression test fails to show a problem. So to those that goes by a compression reading when buying an used saw that is not running beware. Pull the muffler or use a bore scope to check the cylinder condition. Pass if the seller refuses to let you check.

Most times even with just a stuck ring the compression will be below 100 psi. Checking the cylinder visually is just part of my check list of things to do on any 2C due to easy access especially on non runners. Pulling the muffler can save a lot wasted time because with cylinder damage it will just make a 2C unrepairable most times due to costs.

When a shop got to put in $300+ in parts and labor into into a $400 saw it just doesn't make sense to do it; unless, the customer wants to sink this into the equipment. Now if you're doing it for your own use of course it can be repaired for less. On this it looks to around $200 in aftermarket parts when you add the BNC which this one needs along with a spur sprocket.

Call one of the local Stihl dealers and a new Stihl replacement saw runs 410 + tax.

[Luffydog]

had one in shop last week that had about 121psi that wouldn't pop out the compression but would hit and run if you popped it out. after putting in a little oil it would pop it out and start but after running it then back to same ole same ole.

[KE4AVB]

A guy over on Answer Army was using a o-ring slipped over the stem over the CRVs to aid them popping out. Some of the Husqvarna first CRVs were bad to hang in the depress position. Personally if the CRV is giving troubles I just replace them. Only replaced handful so far here over the years.

Now I did have a Husqvarna 55 that I rebuilt that would start and run with the CRV completely missing but sure had an exhaust leak sound until until installed a replacement bolt. The original cylinder didn't have an CRV hole and it was among some my first saw rebuilds but didn't take me long to find it.

[Mr Mower Man]

Pull the muffler or use a bore scope to check the cylinder condition.

Any recommendations on a good bore scope to use? I bought one by Dewalt, and it's pretty much useless. Wish I'd never bought it. Can't hardly see anything with it. What do you guys use?

[bgsengine]

Pull the muffler or use a bore scope to check the cylinder condition.

Any recommendations on a good bore scope to use? I bought one by Dewalt, and it's pretty much useless. Wish I'd never bought it. Can't hardly see anything with it. What do you guys use?

for 2-stroke, just pop the muffler off usually , for other stuff, I got a cheap made in china one off ebay that works off cell phone camera and works reasonably well - enough to judge whether or not to pull apart things further.. only thing is it needs some care to make sure the right angle lens mirror does not fall off the probe

[Luffydog]

I had one that I got from advance auto parts good when I used it when I could. Some plugs that have the smaller 10mm size plugs couldn't fit it in to inspect what really needed to be looked at so I took it back. But wished I had kept it for other things. Don't know about harbor freight but been looking to try one out. Can't remember the brand it was from advance auto parts. They stopped selling them here in store.