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

#1

grumpygrizzly

grumpygrizzly

Well, I think I screwed up..

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


#2

Tiger Small Engine

Tiger Small Engine

grumpygrizzly said:
Well, I think I screwed up..

I'm just looking for things 2 stroke. Kinda stay away from the mowers..
Click to expand...
Work on 2-stroke handheld equipment all the time. What questions do you have?


#3

StarTech

StarTech

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.


#4

addisonjerry79

addisonjerry79

StarTech said:
Here is question for you then. Have you had one to diesel that even the Stihl trained tech couldn't repair Gym Equipment Australia? And BTW the unit idles normally.
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Is there a section on this forum dedicated to small engines, such as 2-stroke motors, weedeaters, chainsaws, and similar equipment? Whether you're looking for troubleshooting advice, maintenance tips, or performance upgrades, a space for discussing these machines would be incredibly useful.


#5

StarTech

StarTech

Here is a couple forums to check out.

Arborist, Chainsaw & Tree Work Forum

Arboristsite is a forum & classifieds website for arborists, chainsaws, tree worker and firewood processing. Forums for all aspects of tree work, chainsaws and tree equipment. Classifieds for chainsaws & arbor tree equipment.
www.arboristsite.com www.arboristsite.com

Outdoor Power Equipment Forum

Outdoor Power Equipment forum for small engine mechanics, tool and equipment stores, and repair shops.
opeforum.com opeforum.com


#6

StarTech

StarTech

StarTech said:
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.
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Here is another couple pieces of info. When running at excess full throttle, the tach shows no spark (ie show the unit is not running but it is) but at idle there is spark as there is normal tach readings.

Stihl HS56Z Hedger under warranty at the time which is why I took it to the dealer for repairs which couldn't find the problem. The tech didn't even know how to do a pressure/vac test.

Tiger for you the question is what would cause no spark at full throttle but yet the hedger is running away? I do know the answer to this and what the root cause was as I repaired the hedger myself.

And this one that I just repaired last week. Echo PAS-225 that would only run at 6000 rpms at full throttle. No problems with compression, spark, or fuel delivery, just would not accel to 7600-8700 rpms even with only the 375 head and no string. Now it is at 8600 with a 450 head and normal string length. BTW no spark arrester present.


#7

Tiger Small Engine

Tiger Small Engine

StarTech said:
Here is another couple pieces of info. When running at excess full throttle, the tach shows no spark (ie show the unit is not running but it is) but at idle there is spark as there is normal tach readings.

Stihl HS56Z Hedger under warranty at the time which is why I took it to the dealer for repairs which couldn't find the problem. The tech didn't even know how to do a pressure/vac test.

Tiger for you the question is what would cause no spark at full throttle but yet the hedger is running away? I do know the answer to this and what the root cause was as I repaired the hedger myself.

And this one that I just repaired last week. Echo PAS-225 that would only run at 6000 rpms at full throttle. No problems with compression, spark, or fuel delivery, just would not accel to 7600-8700 rpms even with only the 375 head and no string. Now it is at 8600 with a 450 head and normal string length. BTW no spark arrester present.
Click to expand...
Two possible causes would be an ignition coil that is slowly failing, and running Tru Fuel instead of pre-mix fuel.


#8

StarTech

StarTech

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.


#9

Scrubcadet10

Scrubcadet10

you can make a post here. doesn't have to be under the brand specific.
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#10

A

Auto Doc's

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


#11

A

Auto Doc's

grumpygrizzly said:
Well, I think I screwed up..

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


#12

StarTech

StarTech

Auto Doc's said:
Excess carbon in the combustion chamber or the muffler was coked up with carbon deposits.
Click to expand...
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.


#13

R

RevB

grumpygrizzly said:
Well, I think I screwed up..

I'm just looking for things 2 stroke. Kinda stay away from the mowers..
Click to expand...
Ask. I'm an old two stroke guy.


#14

K

kjonxx

StarTech said:
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.
Click to expand...
Possibly wrong flywheel or wrong rod? or simpley running too fast when shut down, too much momentum


#15

StarTech

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.


#16

Smithsonite

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.


#17

H

HusqvarnaRider

StarTech said:
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.
Click to expand...
How can it operate with "No Spark"?


#18

R

RevB

HusqvarnaRider said:
How can it operate with "No Spark"?
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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.


#19

R

RevB

kjonxx said:
Possibly wrong flywheel or wrong rod? or simpley running too fast when shut down, too much momentum
Click to expand...
What, exactly, are you "well known" for? 🤫🤔


#20

R

RevB

StarTech said:
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.
Click to expand...
StarTech said:
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.
Click to expand...
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.


#21

H

HusqvarnaRider

RevB said:
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.
Click to expand...
Rev,.... Shouldn't it be called "Perpetual Combustion", since it continued to operate without a "Spark"?

And I'm actually familiar with it somewhat, as in the case of an Oil Burning Furnace, where the Oil Gun, pumped far above the normal amount of oil, in to the Combustion Chamber, but the Thermostat had shut down the "Gun". The "Refractory" in the Combustion Chamber was still hot enough to ignite the oil, which in turn, as the temperature rose, it activated the Blower. That action causes all kinds of Problems, ranging from Soot/Carbon Buildup in the heat-exchanger, to blowing the Oil Gun out of the Furnace, & Causing a Fire.

I'm not claiming to be a "Lawn Mower Mechanic", but I do understand "Combustion" due to my work in HVAC.


#22

Smithsonite

Smithsonite

Back in the day when carbureted cars did this, we called it "dieseling" ... because that's essentially what was happening - fuel was igniting by high compression caused by excessive carbon deposits, or igniting from glowing carbon deposits. Either way, it was no longer a spark-ignition engine at that point.

I had an '85 Monte Carlo that used to diesel so bad it would run on for almost 5 minutes! I'd have to stuff the pedal to the rug to get it to stop, HAHAHA! That thing hit everything but the lottery ...

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