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

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From whats been said, looks like a faulty solenoid, and thus poor fuel delivery has been the likely cause from the beginning.
I guess in future, replace solenoid along with coil, cheap insurance.
If it was my saw, I would be splitting the case, new bearings, and a good flush and inspection of the big end on the crank, lots of bits were shed, and will be all thru the internals.

Your this far in, do it well and do it once.

and a call into stihl going over your purchase history, and the issues and way you have been treated by your dealer would be worth while too.
That's the plan. Since it's already down. I was going to tear it down and rebuild it. I mentioned above that the bearings all seemed fine. Your correct though. Might as well replace while I'm in there. Seals too. I'll see what's said in the next few days with Stihl being involved. I'm fearing the worst. My luck hasn't ever never been great. So I'm already searching for parts and deals.
 
The MDG is only another tool to “help”. As with code scanners for cars, they don’t tell you exactly what happened.
When I get a strange one, my dist will ask for the fuel numbers, then, with a great deal of secrecy, get back to me with which way we’ll proceed. I had just recently, two 661 wipe out cylinders. Serial numbers were very close.
One saw failed, the guy needed a big saw, bought another, that one fail quicker.
They told me to replace cylinders. Didn’t even ask about numbers.
That episode was placed on facebook by the owner of the saws.
Sometimes, the dealer is left in the dark. It’s not always his fault.
And he isn’t incompetent because he doesn’t have all the answers
But he should be damn sure of what he’s claiming is correct.
And also be able to and be willing to get those answers.

My apologies for implying my dealer was anything other than what they are. I wasn't specifically trying to imply malice, just expressing my specific experience over the duration of time I have invested my time and money into the equipment (Stihl), business (ACE) and the individuals (and owners) that are there through the turnover in retail.

I agree. Most of the time, consumers are more into the products than the retailers and our knowledge would be more in that case.

Should always be willing to get the answers. I am the same way. I tell people all the time, "You know, I'm not 100% on this, lets get the answer together. Hold on a second." Sometimes its simple things like what species of plant I'm dealing with that I just forgot. Everyone is different though.
 
Gotcha. Stihl Southeast in Orlando should be your regional distributor..., which you undoubtedly already know by now. Chances are slim you'll get much satisfaction from them on a nearly 5 year old saw..., especially considering the lack of support from your dealer.

Regardless, good luck with it!
 
From whats been said, looks like a faulty solenoid, and thus poor fuel delivery has been the likely cause from the beginning.
I guess in future, replace solenoid along with coil, cheap insurance.
If it was my saw, I would be splitting the case, new bearings, and a good flush and inspection of the big end on the crank, lots of bits were shed, and will be all thru the internals.

Your this far in, do it well and do it once.

and a call into stihl going over your purchase history, and the issues and way you have been treated by your dealer would be worth while too.
Couldn’t agree more, there has got to be particles down in the bottom of that saw, well worth
taking apart to check, couple of bearings, seals and case gasket, only a few hours work in all.
 
Couldn’t agree more, there has got to be particles down in the bottom of that saw, well worth
taking apart to check, couple of bearings, seals and case gasket, only a few hours work in all.
no chance I don't split and cleanout a case after a top end grenades light that one....just takes a little bit of some grinds and the top/bottom end will go again
 
just as additional information. The following is from Redbull on O P E.

Coil/"control unit" -

Mtronic Ver 1.0 coil/control units - 4700C 4700D (don't know the part #) *(edit: part no. was 1144 400 4710 in 2013-2015) - these have lower fuel values and have been associated with allowing the 661 to lean seize.

Mtronic Ver 1.5? 4700E (don't know the part #) (1144 400 4710) - may still be considered Mtronic ver 1.0 - these are supposed to have higher fuel values. (I had one and it ran fine.)

Mtronic ver 2.0 - 4701A - 1144 400 4720 - these had either the same fuel values or higher than 4700E. I had 4 or 5 661s upgraded to this coil. I've run many 661s using this 4701A coil with no issues. As of 8/5/18 midwest stihl no longer sells this coil. You must purchase the 1144 400 4703 or 4704.

FYI "reset procedure" for 4700c, 4700d, 4700e, 4701a = Warm saw, bar chain on. Start saw on choke let it run choke, after 60-90sec (do not touch trigger) push switch all the way off. Restart saw now in run position, let idle (do not touch trigger), after 60-90 sec shut off. Restart saw and do 5 cuts.


Mtronic ver 3.0 coil - 1144 400 4703. I haven't seen an acutal coil in person but I would assume the shorter number on the coil itself would be "4703A". edit: it's actually "4702A" lol.

It gets better...as of yesterday 8/4/18 I noticed they now offer a newer coil yet! - 1144 400 4704. :nut:

as of 8/5/18 at midwest stihl 1144 400 4703 and 1144 400 4704 are in stock and both sell for $111.54

the complete thread can be found here: Coil/"control unit" -

Mtronic Ver 1.0 coil/control units - 4700C 4700D (don't know the part #) - these have lower fuel values and have been associated with allowing the 661 to lean seize.

Mtronic Ver 1.5? 4700E (don't know the part #) - may still be considered Mtronic ver 1.0 - these are supposed to have higher fuel values. (I had one and it ran fine.)

Mtronic ver 2.0 - 4701A - 1144 400 4720 - these had either the same fuel values or higher than 4700E. I had 4 or 5 661s upgraded to this coil. I've run many 661s using this 4701A coil with no issues. As of 8/5/18 midwest stihl no longer sells this coil. You must purchase the 1144 400 4703 or 4704.

FYI "reset procedure" for 4700c, 4700d, 4700e, 4701a = Warm saw, bar chain on. Start saw on choke let it run choke, after 60-90sec (do not touch trigger) push switch all the way off. Restart saw now in run position, let idle (do not touch trigger), after 60-90 sec shut off. Restart saw and do 5 cuts.


Mtronic ver 3.0 coil - 1144 400 4703. I haven't seen an acutal coil in person but I would assume the shorter number on the coil itself would be "4703A". edit: it's actually "4702A" lol.

It gets better...as of yesterday 8/4/18 I noticed they now offer a newer coil yet! - 1144 400 4704. :nut:

http://************/threads/ms661-info-on-new-carb-coil-solenoid-released.13529/

* added part number
 
just as additional information. The following is from Redbull on O P E.

Coil/"control unit" -

Mtronic Ver 1.0 coil/control units - 4700C 4700D (don't know the part #) *(edit: part no. was 1144 400 4710 in 2013-2015) - these have lower fuel values and have been associated with allowing the 661 to lean seize.

Mtronic Ver 1.5? 4700E (don't know the part #) (1144 400 4710) - may still be considered Mtronic ver 1.0 - these are supposed to have higher fuel values. (I had one and it ran fine.)

Mtronic ver 2.0 - 4701A - 1144 400 4720 - these had either the same fuel values or higher than 4700E. I had 4 or 5 661s upgraded to this coil. I've run many 661s using this 4701A coil with no issues. As of 8/5/18 midwest stihl no longer sells this coil. You must purchase the 1144 400 4703 or 4704.

FYI "reset procedure" for 4700c, 4700d, 4700e, 4701a = Warm saw, bar chain on. Start saw on choke let it run choke, after 60-90sec (do not touch trigger) push switch all the way off. Restart saw now in run position, let idle (do not touch trigger), after 60-90 sec shut off. Restart saw and do 5 cuts.


Mtronic ver 3.0 coil - 1144 400 4703. I haven't seen an acutal coil in person but I would assume the shorter number on the coil itself would be "4703A". edit: it's actually "4702A" lol.

It gets better...as of yesterday 8/4/18 I noticed they now offer a newer coil yet! - 1144 400 4704. :nut:

as of 8/5/18 at midwest stihl 1144 400 4703 and 1144 400 4704 are in stock and both sell for $111.54

the complete thread can be found here: Coil/"control unit" -

Mtronic Ver 1.0 coil/control units - 4700C 4700D (don't know the part #) - these have lower fuel values and have been associated with allowing the 661 to lean seize.

Mtronic Ver 1.5? 4700E (don't know the part #) - may still be considered Mtronic ver 1.0 - these are supposed to have higher fuel values. (I had one and it ran fine.)

Mtronic ver 2.0 - 4701A - 1144 400 4720 - these had either the same fuel values or higher than 4700E. I had 4 or 5 661s upgraded to this coil. I've run many 661s using this 4701A coil with no issues. As of 8/5/18 midwest stihl no longer sells this coil. You must purchase the 1144 400 4703 or 4704.

FYI "reset procedure" for 4700c, 4700d, 4700e, 4701a = Warm saw, bar chain on. Start saw on choke let it run choke, after 60-90sec (do not touch trigger) push switch all the way off. Restart saw now in run position, let idle (do not touch trigger), after 60-90 sec shut off. Restart saw and do 5 cuts.


Mtronic ver 3.0 coil - 1144 400 4703. I haven't seen an acutal coil in person but I would assume the shorter number on the coil itself would be "4703A". edit: it's actually "4702A" lol.

It gets better...as of yesterday 8/4/18 I noticed they now offer a newer coil yet! - 1144 400 4704. :nut:

http://************/threads/ms661-info-on-new-carb-coil-solenoid-released.13529/

* added part number
He is actually the one who suggested I contact Stihl.
1d25c0143ed33488bacd8c858020468b.jpg
8939c3c94ac82239171d282ec4448827.jpg
dab0e7f9604c04e2ac545b8dac27ca2e.jpg
 
He is actually the one who suggested I contact Stihl.
1d25c0143ed33488bacd8c858020468b.jpg
8939c3c94ac82239171d282ec4448827.jpg
dab0e7f9604c04e2ac545b8dac27ca2e.jpg


Julian brought up a few good points on other forums ( you can search both our names and they will come up) the Stihl "warranty" has pretty specific EPA wording relating to Stihls requirements to meet EPA standards relating to malfunctioning products. All of which NO dealers give two chits about ...But Stihl USA has to when questioned about it. I cannot link to other "Sites" because the Mods here frown upon it. But the name has been mentioned in this thread already ( outed---like a whistleblower) :)
 
Julian brought up a few good points on other forums ( you can search both our names and they will come up) the Stihl "warranty" has pretty specific EPA wording relating to Stihls requirements to meet EPA standards relating to malfunctioning products. All of which NO dealers give two chits about ...But Stihl USA has to when questioned about it. I cannot link to other "Sites" because the Mods here frown upon it. But the name has been mentioned in this thread already ( outed---like a whistleblower) :)
Awesome yeah I've read on most of the other sites as well. lots of great info out there and where I ended up heading straight to them after I got the back order quote from my dealer...
 
UPDATE: STIHL SOUTHEAST CONTACTED ME DIRECTLY. Official word from still is, I need a new jug and piston. Stihl is not covering anything at this point due to they're being a pre-existing condition in the top end before the parts were installed. Jugs were scored and piston as well. Which the higher RPMs of the calibration mode ultimately put it over its failure point.

Calibration data was taken both from the version 1 and version 3 mtroniks. Everything was within parameter thus nothing is going to be done. Doesn't matter if it's all I've been acting up since month three of its put into service date oh, nothing was caught during the warranty period. and ultimately I did not have the top-end torn down and checked out before the components were put on.

So yeah! Now I need to get my saw back from the dealer and see about getting the top end. Need to make some money first though. Tough pill to swallow! I'll make it happen though.
 
UPDATE: STIHL SOUTHEAST CONTACTED ME DIRECTLY. Official word from still is, I need a new jug and piston. Stihl is not covering anything at this point due to they're being a pre-existing condition in the top end before the parts were installed. Jugs were scored and piston as well. Which the higher RPMs of the calibration mode ultimately put it over its failure point.

Calibration data was taken both from the version 1 and version 3 mtroniks. Everything was within parameter thus nothing is going to be done. Doesn't matter if it's all I've been acting up since month three of its put into service date oh, nothing was caught during the warranty period. and ultimately I did not have the top-end torn down and checked out before the components were put on.

So yeah! Now I need to get my saw back from the dealer and see about getting the top end. Need to make some money first though. Tough pill to swallow! I'll make it happen though.
Do you have any documentation with regards to your inquiries about warrenty services prior to the V3 upgrade ? If you do I wouldn't give up so easy. Saw NEVER ran right. SAW SHOULD run right. Was clearly not meeting EPA guidelines:-(
 
UPDATE: STIHL SOUTHEAST CONTACTED ME DIRECTLY. Official word from still is, I need a new jug and piston. Stihl is not covering anything at this point due to they're being a pre-existing condition in the top end before the parts were installed. Jugs were scored and piston as well. Which the higher RPMs of the calibration mode ultimately put it over its failure point.

Calibration data was taken both from the version 1 and version 3 mtroniks. Everything was within parameter thus nothing is going to be done. Doesn't matter if it's all I've been acting up since month three of its put into service date oh, nothing was caught during the warranty period. and ultimately I did not have the top-end torn down and checked out before the components were put on.

So yeah! Now I need to get my saw back from the dealer and see about getting the top end. Need to make some money first though. Tough pill to swallow! I'll make it happen though.

I know it wont sooth the pain but, I've been dealing with Stihl well over 43 years. I have found, that they are the most lenient manufacturer I work with. There's a lot of speculation and maybes about your failure. Nobody really knows what happened. Tons of info out there. Some right, some wrong, some opinion and some just emotionally driven.
Those fuel numbers tell a lot. My only advice, and take it for what's it's worth, when you feel you have a problem with a new product. don't back down.
And the info I posted about the importance of calibrations was fresh info direct from Stihl. Because I made a call to them yesterday.
They always tell you to calibrate, but never what happens when you don't.
We sell a fair amount of 661's. We sell a ton of MS201T's. Being perfectly honest, we have not seen a large amount of failures due to the system.
Solenoid leakage. That causes rich running and not idle.
Those two 661's that just failed recently is a total mystery.
And yes, they are constantly changing the control units. That doesn't necessarily mean because of problems.
 
FYI "reset procedure" for 4700c, 4700d, 4700e, 4701a = Warm saw, bar chain on. Start saw on choke let it run choke, after 60-90sec (do not touch trigger) push switch all the way off. Restart saw now in run position, let idle (do not touch trigger), after 60-90 sec shut off. Restart saw and do 5 cuts.

What, no magical incantations, incense, holy water, Ouija boards, speaking goats, ordained ministers or exorcism rites needed?
Could no one at Stihl come up with 30 or 40 additional steps?
And how are you supposed to remember all this crap when you're out in the woods?
dizzy.gif
I have trouble remembering my scrench.
 
Do you have any documentation with regards to your inquiries about warrenty services prior to the V3 upgrade ? If you do I wouldn't give up so easy. Saw NEVER ran right. SAW SHOULD run right. Was clearly not meeting EPA guidelines:-(
No, but dealing with the same dealer the whole time and knowing all the mechanics names. Really helped when speaking to Sean from Stihl Southeast in Orlando. the unfortunate part of my end was, Anthony at my Stihl dealer, wasn't inputting when I was bringing my saw in due to him not being able to repeat the issues I was having. After about the sixth time of bring it in for the same issue I got frustrated and decided not to bring it in anymore. I got tired of hearing no for an answer.

I explained and reiterated numerous times to Sean. Unfortunately the warranty is what it is. I'm poor lol. I have to save up now. Going to run my 201tcm and my other saw to try and make money this week. Put off the large wood for awhile.
 
I know it wont sooth the pain but, I've been dealing with Stihl well over 43 years. I have found, that they are the most lenient manufacturer I work with. There's a lot of speculation and maybes about your failure. Nobody really knows what happened. Tons of info out there. Some right, some wrong, some opinion and some just emotionally driven.
Those fuel numbers tell a lot. My only advice, and take it for what's it's worth, when you feel you have a problem with a new product. don't back down.
And the info I posted about the importance of calibrations was fresh info direct from Stihl. Because I made a call to them yesterday.
They always tell you to calibrate, but never what happens when you don't.
We sell a fair amount of 661's. We sell a ton of MS201T's. Being perfectly honest, we have not seen a large amount of failures due to the system.
Solenoid leakage. That causes rich running and not idle.
Those two 661's that just failed recently is a total mystery.
And yes, they are constantly changing the control units. That doesn't necessarily mean because of problems.
Long and short of it. I learned a lesson . I should have been more diligent in my pursuit for resolution when I got the saw. Expensive lesson in lost work and expensive saw down with an expensive repair to boot. I'll fix it soon. Have to work that into the budget now.
 
UPDATE: STIHL SOUTHEAST CONTACTED ME DIRECTLY. Official word from still is, I need a new jug and piston. Stihl is not covering anything at this point due to they're being a pre-existing condition in the top end before the parts were installed. Jugs were scored and piston as well. Which the higher RPMs of the calibration mode ultimately put it over its failure point.

Calibration data was taken both from the version 1 and version 3 mtroniks. Everything was within parameter thus nothing is going to be done. Doesn't matter if it's all I've been acting up since month three of its put into service date oh, nothing was caught during the warranty period. and ultimately I did not have the top-end torn down and checked out before the components were put on.

So yeah! Now I need to get my saw back from the dealer and see about getting the top end. Need to make some money first though. Tough pill to swallow! I'll make it happen though.
Well if Stihl just said the saw had a pre existing condition, then they have just shot themselves in the foot.
Now you need to ask them why the Stihl dealer did not fix this condition.
 
Long and short of it. I learned a lesson . I should have been more diligent in my pursuit for resolution when I got the saw. Expensive lesson in lost work and expensive saw down with an expensive repair to boot. I'll fix it soon. Have to work that into the budget now.
Lots of people get the runaround with dealers, it happened to me regarding
a Husqvarna, every time I need a new saw I think of the ones in my local Husqvarna
dealers, then ask myself, what if I need to take in for a genuine warranty repair,
Seven times I asked me that, and seven times I bought elsewhere, because there was
no way I was going to stand at a counter and be charged for parts that were under
warranty, like two days after buying the small saw, and a few hours after buying
a 372xp, that dealer lost seven sales since, over a 15 euro part, and what should
have been a direct swap of another part that was not the part specified to come
on the saw, so were talking 15 euro part that ended up costing me 40.00 after fitting.
I let them fit it so it would be under warranty, guess what, it broke ten minutes after
getting home.
 
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