Having trouble with stihl 261c rebuild.

[stihlproincky]

What color solenoid?
Did you rebuild the carb

The solenoid is white.

 

[stihlproincky]

There are several versions. Did you compare the new with the old?

Piston is a exact match.

 

[Woodwackr]

The solenoid is white.

Carb rebuilt?

 

[stihlproincky]

Carb rebuilt?

No, do you think I should?

 

[bogieboy]

Buddy, you nailed it! this is a neighbors saw he he abuses it! Hella dull chain. Intake boot checked out, flywheel timing checked out, I ain't got a vac/pressure tester, but I looked over everything and it checked out. Thanks for the input

Given what you are saying, you may need to give the saw a little fuel mix down the throat then... i had to do that when i tebuilt my 661 m tronic, it had learned to the rapidly degrading piston and cylinder, and was so far off it wouldnt start... i use a little plqstic squeeze bottle to feed fuel into the carb until it learns (happens pretty quick on the mtronic 3.0 if you leave it in the triangle positionwhen starting) then proceed to do a reset, given a 2020 saw, would be triangle position, start, run for at leadt 30 sec in that position, peg the gas after 30 sec, it will rev up to about 10k rpm and sit on a limiter there, hold til it releases from the rev limiter and revs out to full rpm, then you can let off, and use the saw normally, you may have to do that several times during the ring seating process, i know i did on my 661.... Thats the 3.0 reset procedure...


Guess it helps diagnosing stuff like this being a certified stihl mechanic by day....LOL

 

[Woodwackr]

Is that kit from stihl or aftermarket?

Dealer kit

 

[Woodwackr]

No, do you think I should?

I finally saw some of the previous posts
You really need to do a vac/pressure test to check for air leaks. Otherwise you can wind up with another blown piston.
I had one a while back that I’d rebuilt but it just wouldn’t start. Rebuilt carb, changed solenoid, etc. I wound up having my Stihl guy plug it in and it came up with carb issue. They replaced the carb and it started right up. I’ve rebuilt 6 of these…this was a first.

 

[stihlproincky]

Would a harbor freight vac tester do? That's local, otherwise I'll have to order it.

 

[stihlproincky]

Given what you are saying, you may need to give the saw a little fuel mix down the throat then... i had to do that when i tebuilt my 661 m tronic, it had learned to the rapidly degrading piston and cylinder, and was so far off it wouldnt start... i use a little plqstic squeeze bottle to feed fuel into the carb until it learns (happens pretty quick on the mtronic 3.0 if you leave it in the triangle positionwhen starting) then proceed to do a reset, given a 2020 saw, would be triangle position, start, run for at leadt 30 sec in that position, peg the gas after 30 sec, it will rev up to about 10k rpm and sit on a limiter there, hold til it releases from the rev limiter and revs out to full rpm, then you can let off, and use the saw normally, you may have to do that several times during the ring seating process, i know i did on my 661.... Thats the 3.0 reset procedure...


Guess it helps diagnosing stuff like this being a certified stihl mechanic by day....LOL

So here's what I heard, put a little mix gas in the throat on the carb, start on triangle once started let it run for 30 seconds on triangle, peg the gas ( hold it down?) Then rev it up to 10k rpm? Sorry I'm still learning.

 

[MemphisMechanic]

So here's what I heard, put a little mix gas in the throat on the carb, start on triangle once started let it run for 30 seconds on triangle, peg the gas ( hold it down?) Then rev it up to 10k rpm? Sorry I'm still learning.

No. Start it on triangle let idle for 30 sec. Pin throttle wide open. It will rev to 10, hold for a bit, then run up to full RPM without you doing anything besides contining to hold the trigger down.

Let it scream for a few seconds then it’s finished with it’s reset and ready to use.

 

[stihlproincky]

No. Start it on triangle let idle for 30 sec. Pin throttle wide open. It will rev to 10, hold for a bit, then run up to full RPM without you doing anything besides contining to hold the trigger down.

Let it scream for a few seconds then it’s finished with it’s reset and ready to use.

Thanks, I thought I had it wrong that's why I asked

 

[bogieboy]

So here's what I heard, put a little mix gas in the throat on the carb, start on triangle once started let it run for 30 seconds on triangle, peg the gas ( hold it down?) Then rev it up to 10k rpm? Sorry I'm still learning.

Almost...everything is correct til your question, which is yes, hold the trigger full throttle after the 30 sec, the saw will act lije it is sitting on a rev limiter at about 10k, you will hear it vary a little bit, maybe 500 rpm one way or another, keep holding the throttle full til it revs up to full rpm, then it has learned the current conditions that the saw requires to run. Let go of the throttle and (not required but i like to do this with my saws) once back idling, shut it down and restart

No need to appologise either, you are learning, which means you cant ask enough questions...LOL i learned from taking stihl classes that my employer(s) both past and present have sent me to.

And after typing all that, i see @MemphisMechanic had already let you know what to do LOL but its all good!

 

[drf256]

The LAST thing you should do is a factory reset on a saw that blew up for no known reason. You should get it to at least run first.

I’m not a fan of the V2 reset. Some suspect it’s caused the piston cracking problems in the version 1 462 (it has V2 MT). I used to reset every MT saw I did after porting regardless of version. I never do it anymore. In a few cuts, the saw will reset itself.

You better make sure you know why that saw failed the first time, otherwise you will just toast it again.

 

[bogieboy]

The LAST thing you should do is a factory reset on a saw that blew up for no known reason. You should get it to at least run first.

I’m not a fan of the V2 reset. Some suspect it’s caused the piston cracking problems in the version 1 462 (it has V2 MT). I used to reset every MT saw I did after porting regardless of version. I never do it anymore. In a few cuts, the saw will reset itself.

You better make sure you know why that saw failed the first time, otherwise you will just toast it again.

This is a v3 saw, so.... whats your point? Also we determined a super dull chain was the cause of the failure... this particular saw wont start and idle currently with a fresh topend... that needs a reset.... assuming that the cylinder doesnt have any air leaks

 

[sawmikaze]

The LAST thing you should do is a factory reset on a saw that blew up for no known reason. You should get it to at least run first.

I’m not a fan of the V2 reset. Some suspect it’s caused the piston cracking problems in the version 1 462 (it has V2 MT). I used to reset every MT saw I did after porting regardless of version. I never do it anymore. In a few cuts, the saw will reset itself.

You better make sure you know why that saw failed the first time, otherwise you will just toast it again.

I bought a 462 in 2019 when it was first released here and it was V3, I've never heard of or even seen a version 2 462.

 

[Moparmyway]

I bought a 462 in 2019 when it was first released here and it was V3, I've never heard of or even seen a version 2 462.

Mine is a 2018, and it’s a V3

 

[bogieboy]

View attachment 419917

Mine is a 2018, and it’s a V3

And my '17 661 is also v3.... so.... yeah.... i know Doc is well respected but.... hmmm

 

[sawmikaze]

View attachment 419917

Mine is a 2018, and it’s a V3

Mine was made in 18 but I couldn't get it until spring of 19.

The piston finally cracked a few weeks back.

 

[drf256]

I used the wrong term guys. I meant the MT that had the first type of reset (run on choke for 30 sec) vs the newer type of reset.

In referring to the 462, I don’t believe any of them had the first version type of MT reset. My abbreviations were incorrect. Whether the 462 were V2 or V3 I am unsure, I just know that they all had the new type reset.

The 462 changed piston style and case, also cylinder. They were having piston cracking problems on the intake side of the skirt. Some postulated that it was from guys doing the reset procedure because of how long the saw just piss revs.

 

[drf256]

This is a v3 saw, so.... whats your point? Also we determined a super dull chain was the cause of the failure... this particular saw wont start and idle currently with a fresh topend... that needs a reset.... assuming that the cylinder doesnt have any air leaks

My point is that the new style reset requires a prolonged high rpm unloaded period. If you have an inherent problem that roasted the piston, you would want the saw at least running before the reset.

The MT system is very forgiving. I’ve seen it compensate for massive air leaks. If you forget to hook the wires back up to the solenoid, the default is pig rich to save the saw.

The saw should be able to at least idle and run (maybe not great) without a reset. If it’s a stock 261C with a normal sized bar, it would take a lot of time with a dull chain to roast it. The MT would still have the flexibility to fatten the saw up.

I’m interested to know what the cause is. The OP asked for help, I commented. Just trying to keep him from ruining his work. I don’t really GAF what happens, was trying to help. And BTW, that’s not a “fresh” top end.

Carry on…