Is there a small engine area on this forum? I.e. 2 strokes, weedeaters, chainsaws...etc?

[Auto Doc's]

Well, I think I screwed up..

I'm just looking for things 2 stroke. Kinda stay away from the mowers..

Go to the home tab at the top of the page, click on it and the drop down will show many 2 stroke brands and forums.

 

[StarTech]

Excess carbon in the combustion chamber or the muffler was coked up with carbon deposits.

That wasn't either. I actually did a decarbonization on it which didn't resolve the problem. BTW none of the local Stihl can even get the decarbonation fluid so going there you are SOL most times.

That is something I have been running into lately on both Stihl and Echo 2 cycles where carbon is locking up the cylinders. And spark arresters have always been a problem area so they get pulled and clean if needed on every unit.

 

[RevB]

Well, I think I screwed up..

I'm just looking for things 2 stroke. Kinda stay away from the mowers..

Ask. I'm an old two stroke guy.

 

[kjonxx]

Here is question for you then. Have you had one to diesel that even the Stihl trained tech couldn't repair? And BTW the unit idles normally.

Possibly wrong flywheel or wrong rod? or simpley running too fast when shut down, too much momentum

 

[StarTech]

Oh well no one knows what caused the problem but I do. I glad I charge to customer $100 to fix it and $95 of that is profit.

 

[Smithsonite]

Only other thing if not carbon would be a piece of head gasket not machined correctly, sticking into the combustion chamber and glowing red.

Actually one more thing. Wrong type of spark plug with the wrong heat range. If a projected resistor plug were to get hot enough it could definitely cause this.

 

[HusqvarnaRider]

Running standard oil/fuel mix. I know the customer was using my Pro oil packets; therefore mixing the fuel on as needed basis for all of their Stihl and Echo equipment and I was the same mixture myself.

And coil was working as designed. Cutting ignition spark at 9300-9500 rpm. IE speed limiter activating at 9300-9500 rpm.

Neither was the cause of the problem. Keep thinking as it was definitely dieseling. Definitely was running well above 9500 rpm with no electrical spark.

How can it operate with "No Spark"?

 

[RevB]

How can it operate with "No Spark"?

Called pre-ignition. A hot bit of carbon, a sliver of metal that is hot enough to ignite fuel vapor. https://en.m.wikipedia.org/wiki/Pre-ignition

This is what separates mechanics from on-lookers.

 

[RevB]

Possibly wrong flywheel or wrong rod? or simpley running too fast when shut down, too much momentum

What, exactly, are you "well known" for?

 

[RevB]

That wasn't either. I actually did a decarbonization on it which didn't resolve the problem. BTW none of the local Stihl can even get the decarbonation fluid so going there you are SOL most times.

That is something I have been running into lately on both Stihl and Echo 2 cycles where carbon is locking up the cylinders. And spark arresters have always been a problem area so they get pulled and clean if needed on every unit.

That wasn't either. I actually did a decarbonization on it which didn't resolve the problem. BTW none of the local Stihl can even get the decarbonation fluid so going there you are SOL most times.

That is something I have been running into lately on both Stihl and Echo 2 cycles where carbon is locking up the cylinders. And spark arresters have always been a problem area so they get pulled and clean if needed on every unit.

I've never had to do a decarbon. Ever. Everything I own that is air cooled two stroke and under 8000 or under RPM runs close to 100:1 gas/oil. Including Ultralight acft engines. Rotax reccomemends decarbon every 50 hours. That's just insane. Ball bearings and needle bearings require scant amounts of lubrication. Piston skirts and rings about the same. 1200 hours on a Hirth with zero decarbon, original plugs that look like four stroke (lighter white tip leading to tan on the insulator), and I can still look into one of the spark plug holes and see the piston casting markings and the rings are still free. 20 year old Tanaka blowers and weed eaters the same. So go ahead and decarbon....more oil is not better in the two stroke world. If this were a TZ750 or a Gamma 500 whose RPMs were reaching for the moon, I'd be down in the 50 to 60:1 range.