Spark Plug Pics...

[CaseyForrest]

This one is out of my 660.....

I used regular Stihl oil in this for the first gallon. Its been about 8 gallons of Stihl Ultra oil through it since, 90% of that has been in the mill. The top of the piston does have some buildup, but I equate that to running rich.

This one is out of the 361....

This uses the same mix. The top of the 361 piston, however, was clean as can be, looked like new.

Sorry about the blurr, I used the wrong camera to take close-ups.

 

[CaseyForrest]

Yeah, after I pulled the 361 plug, I gave the high side about 1/16th of a turn out.

Im surprised at the 660 plug though, I wiped it down with a rag and it looks great. No build-up. Especially how hard Ive been on it.

 

[Lakeside53]

Yep.. they look good. The 361's always look "lean'ish". Check out the pattern on the top of the 361 piston - there will be a clean area and a couple with slight buildup. The 361 is about as "clean" (epa) as you can make a 2 smoker before stratocharging etc.. Stihl s been earning EPA credits with this saw for three years. No more credits after January 1st though...

 

[CaseyForrest]

Side note on the 361....(and since I started this thread, I can go off topic if I so desire!!)

Noticed not to long ago that the Decomp never stays down. Example: I push it down and give the rope a pull, and it pops back out. Just the compression alone makes it pop out...so anyway, it has always taken about 5 pulls cold on choke before it goes, then choke off and about 3 more pulls to get her going.

Not sure if this is related, but replaced the Decomp with a plug and it fired on the first pull on choke, and first pull choke off and away we went.

The Decomp apparently had been leaking around the seal as there was quite the build-up of gas-oil and anything that likes to stick to mix.

 

[Lakeside53]

I find almost all saws start better without the decomp... even my 066... When milling, it runs real rich. If I use the decomp after stopping, it will often flood the plug (my fault, but its staying that way). NO decomp has it's own issues on the 066 when on a mill, but...


Most 361s I start (and I start a lot of them) fire up after about 4-6 pulls from cold. I believe it's the "lean" engine that makes them slower to start than say a 360. The decomp - most seen to work fine with it... if they pop out when turning over it usually because they are a tad lean on the L - you get a tiny fire... but only one that's just enough to move the valve. The ignition being very retarded at start rpms might have something to do with it also. I generally ignore the decomp. If it pops - fine - and just keep pulling. Helps to have the Elastostart handle though!

 

[CaseyForrest]

Andy, I thought about it popping a little as I pull, but it doesnt matter whether I pull slow, or fast. Once the piston produces enough compression, the button pops. Most of the time its before TDC.

 

[Lakeside53]

weird.. maybe it was faulty.. Maybe the Ultra lube?

 

[CaseyForrest]

Yeah, I remembered I had a new plug laying around...so thats what itll be from now on. Doesnt really pull that hard anyway.....The 660 is a different story.

Heres one Im sure you can relate on....Push the button on the 660, give her a few yanks and it pops just enough to push the button out and you think its going to go, but doesnt.....Yanks the handle right out of your hand...that hurts.

 

[Freakingstang]

Yeah, I remembered I had a new plug laying around...so thats what itll be from now on. Doesnt really pull that hard anyway.....The 660 is a different story.

Heres one Im sure you can relate on....Push the button on the 660, give her a few yanks and it pops just enough to push the button out and you think its going to go, but doesnt.....Yanks the handle right out of your hand...that hurts.

Don't be a girl.

Seriously, if you don't give it a hard, fast jerk, it will bite you. If you try to pull it easy, it does it worse. Don't fear the king.

 

[Lakeside53]

Heres one Im sure you can relate on....Push the button on the 660, give her a few yanks and it pops just enough to push the button out and you think its going to go, but doesnt.....Yanks the handle right out of your hand...that hurts.

Oh yes.... now try that on an 880!!!!

 

[Lakeside53]

Don't be a girl.

Seriously, if you don't give it a hard, fast jerk, it will bite you. If you try to pull it easy, it does it worse. Don't fear the king.

sure.. but easier said than done sometimes... like when it's on the mill in the log!!!

 

[CaseyForrest]

Don't be a girl.

Seriously, if you don't give it a hard, fast jerk, it will bite you. If you try to pull it easy, it does it worse. Don't fear the king.

Youve been awful sprye lately....You been cut off or something?? hahaha

Just as Lake said, its not always easy to give it a good yank. Allot of the time its on it side, and I find myself cranking it over slowly to get the piston just BTDC, and then giving her a yank. Most of the time it goes, but sometimes it doesnt.

 

[IchWarriorMkII]

Me thinks my 353 is a little rich...

Maybe a lot richer than I think.

 

[CaseyForrest]

Better too rich than too lean. I need to find a GOOD, small tach. Ill do a search, but if anyone wants to chime in with suggestions while Im looking, I wont mind.

 

[Freakingstang]

Youve been awful sprye lately....You been cut off or something?? hahaha

Just as Lake said, its not always easy to give it a good yank. Allot of the time its on it side, and I find myself cranking it over slowly to get the piston just BTDC, and then giving her a yank. Most of the time it goes, but sometimes it doesnt.

It's not that I'm being sprye lately, just everyone is so sensitive lately...... Sorry, I never imagined so many men running chainsaws with really soft feelings.

I was talking from experience... Although I did not think about the saw being sideways in a mill. Makes me look forward to the 084.... At least I'll have an elastostart on it.

 

[CaseyForrest]

Oh yes.... now try that on an 880!!!!

See, you go and say that and I have to re re-think my Ripsaw/880 dilema.

 

[IchWarriorMkII]

Mines a much darker brown, not black but a rich chocolate...


I think I'll knock it back a little off the limiter tabs to see how it runs. It was also getting rough as the saw warmed up, also leading me to believe its a little rich.

 

[bwalker]

Both plugs look rich, especially the 660.
I have seen motors ran for thousands of miles overly rich and they have silver piston domes. All that extra fuel washes the carbon right off.

 

[Lakeside53]

See, you go and say that and I have to re re-think my Ripsaw/880 dilema.

:hmm3grin2orange: :hmm3grin2orange: :hmm3grin2orange: :hmm3grin2orange: :hmm3grin2orange:

 

[Lakeside53]

Both plugs look rich, especially the 660.
I have seen motors ran for thousands of miles overly rich and they have silver piston domes. All that extra fuel washes the carbon right off.

1000's of miles? -we are talking chainsaws... maybe applicable to the 660 when milling, but not so with the 361 - intermittent power use.

I don't believe the 361 is too rich.. That's very typical of a good running 361 plug... almost white/gray on the tip. Only one side of the plug is really exposed in the flame - something to do with the way the combustion gasses swirl, and I only see this on Stihl with the 361. If you are looking at the buildup around the edge of the threads - normal, and on the last picture you can see where it breaks from gray to black (cooler side).

I doubt the 361 dome is "silver" all over. There is a very distinct pattern of silver and black on 361's. I'll take picture next time I have one down.