MS661C 2015 M-Tronic V3 4702A Coil Calibration Now Grenaded Piston

[PogoInTheWoods]

You already know my opinion of your dealer and their level of 'expertise'. Worthless when the rubber meets the road. They like your money but not your problems.

Clean up your bottom end if the big end is still ok and run the cylinder you already cleaned up with a Meteor piston for 40 bux and don't look back. If you're nervous about the cylinder, go with a complete Meteor top end for $144. You have very little to lose at this point. Meteor is known for very high quality parts that meet or exceed OEM specs in most cases. Much higher quality in most all cases than the Chinese alternatives and Caber rings come standard. Here is a link for your convenience:

Only 1 left there. https://www.wolfcreeksawshop.com/pr...it-for-stihl-ms661-ms661c-56mm-1144-020-1200/

I wouldn't put another Stihl top end on that saw just on general principles alone (and the sour taste) at this point. But that's just me. I've had Meteors on my 044, 066, and 288xp for almost 10 years and I run those saws like they are meant to be run. Not one issue with any of them. I run 40:1 high quality synthetic oil and E-free 91 octane. You should do the same. Do not skimp on the quality of your mix oil.

Good luck with it.

 

[skygear]

Ok guys. Getting her off the shelf and putting her together again.

Decided I want to attempt a Big bore 58mm build or a 56mm race piston from CCC - What head do I get? What ring if I stick with the 56mm? the 1mm or 1.2mm

A cheap ring and head kit and use the head and accessories to put the race piston in? Direction here would be appreciated.

 

[skygear]

Should I stick one of the race piston popups in her? I don't know what the difference between a 1.2mm ring and a 1mm ring will do for me. Should I try using my stock head or get a kit?

 

[skygear]

Here are the pistons I'm looking at. I don't think the M-tronic can handle the 58mm version. Which one? Or just get a Meteor kit? https://www.ebay.com/itm/Meteor-Nik...MS661-MS661C-56mm-1144-020-1200/173392717176? Or HL kit? https://www.hlsproparts.com/Stihl-070-090-cylinder-piston-assembly-58mm-p/h30507.htm?

https://www.chainsawcc.com/race-pistons

 

[skygear]

Interesting this came up in my feed while searching

Genuine from overseas for ~$125 less than list @ ~$285. https://www.ebay.com/itm/Genuine-OE...Gasket-1144-020-1202-1200-Track/292251992729?

Meteor for ~$145 https://www.ebay.com/itm/Meteor-Nik...MS661-MS661C-56mm-1144-020-1200/173392717176?

Highway for ~$120 https://www.ebay.com/itm/Hyway-Nika...MS661-MS661C-56mm-1144-020-1200/172307682506?

 

[huskihl]

On the Wiseco pistons, the thin rings are not compatible with stihl cylinder plating. His 1.2 MM ring piston is what you want to run in a stock cylinder bore

 

[huskihl]

In my experience, the 56MM meteor kit only runs about 75% as strong as the OEM. So I’d wager a guess that the 58 MM version still isn’t as strong as stock OEM

 

[skygear]

On the Wesco pistons, the thin rings are not compatible with stihl cylinder plating. His 1.2 MM ring piston is what you want to run in a stock cylinder bore

In my experience, the 56MM meteor kit only runs about 75% as strong as the OEM. So I’d wager a guess that the 58 MM version still isn’t as strong as stock OEM

Appreciate you. I found him here https://o p e f o r u m.com/threads/new-pistons-and-future-pistons.15655/

Would you recommend 100% OEM then? stock piston and jug over a stock jug and the 56mm/1.2mm popup piston?

 

[huskihl]

Appreciate you. I found him here https://o p e f o r u m.com/threads/new-pistons-and-future-pistons.15655/

Would you recommend 100% OEM then? stock piston and jug over a stock jug and the 56mm/1.2mm popup piston?

That’s totally up to you. The Wiseco is a great piston. But if you want to actually feel the difference I’d get it ported

 

[Mad Professor]

After reading 1/2 of this thread:

1) I am glad all my Stihls are > 20 years old. I can fix them CHEAP!

2) I am glad none are metronic = nightmare for person to work on

3) I am happy that the Stihl reps Stihl suck, they are in all reality useless POS. I have talked with some and they don't know their shoe size from a chain size. I complained to Stihl USA, they are dimmer wits. Maybe we need to talk to the Germans?

 

[PogoInTheWoods]

Maybe we need to talk to the Germans?

That's what I do.

And I think I'd still just put a Meteor piston in the thing until you're comfortable that the v3.0 setup is working as it should and the kit didn't come with a bumb solenoid out of the box or something else was (is?)weird with the ECM which ran it lean enough to immediately trash it the last time around. Provided your mix was cool, you still don't know for sure why it grenaded in the first place. BTW, it's ok to warm up a v3.0 saw and then shut it off before doing an actual calibration. Some would even say it's advisable with a brand new build to minimize the chances of cold seizure.

 

[skygear]

That's what I do.

And I think I'd still just put a Meteor piston in the thing until you're comfortable that the v3.0 setup is working as it should and the kit didn't come with a bumb solenoid out of the box or something else was (is?)weird with the ECM which ran it lean enough to immediately trash it the last time around. Provided your mix was cool, you still don't know for sure why it grenaded in the first place. BTW, it's ok to warm up a v3.0 saw and then shut it off before doing an actual calibration. Some would even say it's advisable with a brand new build to minimize the chances of cold seizure.

My initial startup was a warmup then went straight into the calibration. I'm near the gulf. Could have been contamination from salt air or something else. ‍ Playing devils advocate here.

My 'JUG' isn't perfect right now but more than sufficient to run a new piston in her. No scratches on the wall or coating except for a tiny one 2.04mm from the top of the head. Then the dent in the top of the cylinder from the old ring. Based on my measurements on where the stock ring starts, the one on the wall will not interfere with compression or blow by. The one on the cylinder head has been corrected as best as I can by light tapping with a brass punch and hammer until it is flat with the surface and sanding the rest lightly with 2000grit.

 

[skygear]

After reading 1/2 of this thread:

1) I am glad all my Stihls are > 20 years old. I can fix them CHEAP!

2) I am glad none are metronic = nightmare for person to work on

3) I am happy that the Stihl reps Stihl suck, they are in all reality useless POS. I have talked with some and they don't know their shoe size from a chain size. I complained to Stihl USA, they are dimmer wits. Maybe we need to talk to the Germans?

I will say I've always liked their pro products. Hadn't had any bad experiences with them until I ran into this one. Product knowledge was always lacking at the dealer level. Hard to have retail employees be career mechanics and salesman in an Ace Hardware. Where they are expected to sell everything else in the store and be experts on everything hardware. The "Ace" brand are all individual owned and how they are able to sell their products. Most owners are just as volatile and uninvolved as a big box store. They grow tired of an employee and instead of correcting issues, fire someone. Same on the inverse of that. We don't invest enough time, effort, and money into the employees that might want to be a small engine mechanic for the rest of their lives. We look at people as a disposable asset ready to replace them at a moments notice. Thats where the hang up is. If I could do a cushy retail 9-5 or similar and make enough to own a house and support my 4 children and I for the rest of our lives. I don't think I would hesitate at doing it. I know that is not a reality and why I go out and book thousands of dollars of work when we need money. I enjoy cutting. I love climbing. I enjoy my clients and love that they allow me to take my time and I'm not rushed to get my work done. I'm fast when I need to be, but take my time and not damage anything. I always leave a clean worksite too. After a month, I send thank you cards to my clients. Then for a couple years after, I send them Christmas cards, and or birthday cards if I have that info on file.

That kind of customer service and appreciation is something I grew up with and will continue to provide.

Unfortunately, I haven't seen any businesses come close to the level of service I am capable of and currently provide. I'm the little guy. I have my truck and my 4 kids. No crane, grapple truck, lift, miniskidsteer or anything. I show up, work hard, get all my debris to the curb and call a buddy with a 16 yarder grapple to pick it up.

___ I bought into the M-Tronic. Was hoping for a better experience since We travel over the US for leisure in our truck. Then might pickup some work wherever and whatever elevation we are at.

I have to get this one running again. My 201T w/16" bar has been great but I have some big wood scheduled out soon. Don't want to play in the wood for hours on this site. It isn't going to be pleasant with all the mosquitos on this property. I sat her on the shelf in a box discouraged for far too long.

 

[skygear]

While I have some of your attention. Can I get some opinions on some of the accessories I'm adding?

My chain sprocket cover has some abnormal wear from where its stored on the truck and in need of replacement. I have the standard one 1144 640 1704 with the captive nuts and solid dogs.
Going to grab the 1144 640 1709 with the skeletonize dogs, skirted/ flared bottom for better chip clearing, and regular bar nuts. - Can I modify this to accept captive nuts? I have the crimper tool.

I put the rescue saw pull start handle/ snow blower pull start glove handle on it. Sometimes my hands don't work properly and this extra surface area helps. Bad motorcycle accident years ago. Residual issues after the fact.

Feelings on full wrap handles? Initially I wanted the Arctic 661. My region couldn't get it and I didn't want to deal with warranty issues from buying off Ebay. Full wrap siulll looks interesting to me years after the fact. I can also see where it would get in the way on some of my low cuts on stumps too. OPINIONS?

Anything extra I should be looking at while I have her torn down? Larger/ different oiler? Solid oiler gear vs the nylon one?

 

[PogoInTheWoods]

Sounds like you're an honorable man running an honorable business. Props to you.

You'll get the saw figured out. My advice would simply be to not get too fancy with it right away. You can get it ported later after you know the basics are working the way they're supposed to. M-trons are fine when everything works right..., which is most of the time. When they don't, you're SOL.

 

[skygear]

Went with my stock head and stock piston for now. In the process of putting her together, I snapped a ring on one of the pins with the ring compression tool. Wasn't sure what the thickness on one side was when I lined up everything. Gave it a little extra squeeze and the iron ring gave way. Snapped right in two. Ordered another set of them. In the mean time, I decided to try to run a single ring. She runs and cuts.thats important. Piston rings will be in Monday. Don't need to do anything with her until then.

 

[huskihl]

Went with my stock head and stock piston for now. In the process of putting her together, I snapped a ring on one of the pins with the ring compression tool. Wasn't sure what the thickness on one side was when I lined up everything. Gave it a little extra squeeze and the iron ring gave way. Snapped right in two. Ordered another set of them. In the mean time, I decided to try to run a single ring. She runs and cuts.thats important. Piston rings will be in Monday. Don't need to do anything with her until then.

I’ve run a single top ring in quite a few of them I’ve ported due to the bottom ring gap next to the exhaust port. They actually run a little better with only one ring.

 

[skygear]

I’ve run a single top ring in quite a few of them I’ve ported due to the bottom ring gap next to the exhaust port. They actually run a little better with only one ring.

Where are people getting the "ports" for the multi port muffler mods? I ordered 2 screw on ones from Ebay, they seem a bit small and too low to the muffler. Like the lip of the muffler will interfere with the flow of the exhaust.

 

[huskihl]

Where are people getting the "ports" for the multi port muffler mods? I ordered 2 screw on ones from Ebay, they seem a bit small and too low to the muffler. Like the lip of the muffler will interfere with the flow of the exhaust.

661 is a little bit tougher than most to get extra deflectors on. There is a fella that goes by Red97 on o p e forum who sells a variety of stamped deflectors. You'd need to trim, bend, drill, or weld it in place

 

[skygear]

Redbull661 has some nice looking ones that he bolted and welded on.


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Thanks again Kevin. I'll track them down. These are substantially larger than the 2 Ebay ones I got.