3 hours down the tube......

[MotorSeven]

Just got done helping a neighbor C&S about 8 cords:

I have about 11-12 cords to do and started on the los today. My 361 was running fine, then I swear I heard something clog the carb...it started to stumble. Let it idle for a few, start a cut, half way through it would start stumbling again. I grabbed another saw and finished for the morning(sun was a gettin hot). Took the saw in the shop and found a "shattered carb"...wtf?:

Bottom bracket was broken off, the two center bolts were still tight. This one was modded so removing the internal baffle might have weakened it. So off to the Millermatic I went:

Then I used the flat side of mty 12" cut off saw to square it all back up:

more to follow............

 

[MotorSeven]

So I really didn't think the carb was related to the stumble...but there is alway hope. Nope....it still stumbled. So did a quick breakdown and cleaned out the carb. Diaphram's looked decent, so I just put it back together....same issue. Back apart, replaced the diaphram's...same issue. took it apart again and put the carb in the ultrasonic cleaner for 45 min & two different solutions. Back together....yahhhp..same issue.
Sooo, I went back to basic's...check the spark plug.....

Looks ok right....NOT! When you tilt it towards the spark end this happens:

The insulator is completely broke off and sliding up and down on the electrode...so I was chasing my tail for quite some time

Anyway, gut it all back together and it runs perfect...again.........

 

[redfin]

You could look at it like 3 hrs down the tube or 180 bones still in your pocket. Good work.

 

[blsnelling]

You dodged a bullet with that spark plug! Thank goodness it didn't drop parts into the cylinder.

 

[Bluefish]

Good save. Could a been a lot worse. Russ

 

[bag-o-donuts]

Hurry to the nearest store & buy a lottery ticket!

 

[JC360]

Nice catch! Saved that time and then some on a rebuild.

 

[MotorSeven]

Good way to look at it...if not for the spark plug I would not have noticed the muffler and just kept running it.............would not have ended good. I have never seen an insulator break like that...real odd that it was sliding back and forth creating interrupted spark.

 

[Wagnerwerks]

I have been buying, stocking and using spark plugs for almost 20years. I have also been using Bosch plugs in German cars for 21 years. I've installed and sold thousands. I only ever had one issue like yours, but unfortunately, that time I ran a ceramic center from a plug through a clean 16v 2.0 vw engine that burned oil after that until it's untimely death shortly after. Sucks when parts fail.... You dodged a bullet. I switched to ngk..lol.

 

[MotorSeven]

Looking on fleabay for mufflers...new one's from Hong Kong for $15? Anyone tried one...?

 

[MotorSeven]

Wagner, it was not a Bosh......crap it's down at the shop...started with a "D". I bought the saw used 5-6 years ago and never really looked at the plug.

 

[Wagnerwerks]

It may not have been the plugs fault that it failed. Maybe it got to hot from a lean condition from the turbo... I don't know, but I turned all paranoid...


Probably a denso.

 

[rob066]

I had a Champion plug do the same thing. I didnt get so lucky it insinerated and looked like sand went through my cylinder.

 

[ncfarmboy]

I picked up a box of 10 Denso plugs buck a piece to try em. 1 ran for ten min. 3 dead in the box 6 in the trash. Junk IMO others may have a better experience but I tend to doubt it.
Shep

 

[MotorSeven]

Yes...it was a Denso....it has been in the 361 for a loooong time. I had one new Bosh left in my parts box...runs much better now.