661 flooding problem

[porsche965]

The only parameter MTronic can monitor is RPMs. It adjusts the fuel and checks to see how it affected RPMs, over and over, many times per second. It knows nothing of elevation, fuel mix, barometric pressure, fuel octane, or any other performance affecting variable. It works entirely off RPMs.

But all those factors affect RPMs so one could say they are somewhat relative. ?? Tomatoes, tomatos, however you want to say it. Let's just get this saw making chips again!

Anyway, try the reset, new plug, fuel/mix and report back.

 

[blsnelling]

I cut from about 7:30-noon and then again in the afternoon for several hrs on Thus. Not as much run time on Fri, only half day cutting, but same issue occurred.
cut up several trees I had dropped last year as well as around 10 more dead (bark beetle) trees this year...probably 6cd of rounds from 8" to 30" diameter.

Saw ran fine down at sea level when I first got it and after getting it back from you. This was the first time using the K2 and at 8000' in altitude. When running it was fine, cut great, ran great, idled fine. The problem was only when shutting it off and then trying to restart after a few minutes. It acted as if I had choked an already warmed up saw...including smelling gas when pulling cord...over and over again. I did try one pull with choke just to see if any difference, none.
pulling until my arm fell off would eventually get it started but it was easier to just pull the plug and let it dry out. after that, started with 1 pull each time this happened.

Twilight Zone saw?

...cue music...

I would most certainly perform the reset procedure. Also, I would not use the start position to start a hot saw.

 

[blsnelling]

But all those factors affect RPMs so one could say they are somewhat relative. ?? Anyway, try the reset, new plug, fuel/mix and report back.

Absolutely they affect RPMs, but MTronic doesn't have the ability to monitor any of these other variables. That's the beauty of it...It doesn't have to

 

[singinwoodwackr]

The only parameter MTronic can monitor is RPMs. It adjusts the fuel and checks to see how it affected RPMs, over and over, many times per second. It knows nothing of elevation, fuel mix, barometric pressure, fuel octane, or any other performance affecting variable. It works entirely off RPMs.

odd. then how do you run these saws at various elevations w/o having any way to adjust things?
I never adjusted the carb on the 066s for elevation and had no issues. rpms tended to run a little lower than at 200' but saw performance was about the same.
when cutting the new one seemed to run great.

 

[singinwoodwackr]

I would most certainly perform the reset procedure. Also, I would not use the start position to start a hot saw.

I've been leaving the switch where it was after shutting down and it always started right back up...down here in the flat lands.

 

[maulhead]

got this from another thread, "With the reset procedure, I would do 90 seconds at Start, shut it down. Do 90 sec on Run, shut it down. Then start it and put it in some big wood."

this the 'reset' procedure? can't find anything in the owners manual

That is pretty much it, I got this from a 441c thread a few years ago and I have been using this reset when changing in elevation and it has worked for me.

1. With the chain brake engaged…
Hold throttle and set start lever to Start position
Start saw and let idle in Start position for 90 seconds
Immediately move lever to Stop position
This will reset the carb to original factory setting.

2. With the chain brake engaged…
Start saw in Run position
Let idle in Run position for 90 seconds
Immediately move lever to Stop position
This will calibrate the idling characteristics of the saw.

3. With the chain brake engaged…
a. Hold throttle and set start lever to Start position
b. Start saw then Blip throttle to bring the machine to the Run position
c. Disengage chain brake and make five uniform cuts through a log.
d. This will calibrate the full throttle characteristics of the saw.

Done.

I've done it both with and without the brake engaged, I think it is just a safety thing (dont hold me to that) at the times I done it without the chain brake on, it does spin the chain.

One of my other ported m/t saws I forgot to do the reset from a 3000' elevation change, and did like your saw ran fine on cold start, set the saw down for a few minutes and it would not restart hot 15-20 pulls later no start, then I held the throttle wide open it finally popped off, I let it cool off and did the reset and it was back to normal one pull when hot.

 

[blsnelling]

From what it sounds like, the reset procedure must set the operating window within which MTronic works for a given set of variables. When these variables change significantly, the reset procedure needs performed in order to adjust that operating window. Going from sea level to 8000' elevation is a HUGE change. Quite frankly, I'm disappointed this reset procedure is required. IMHO, this should happen automatically.

 

[singinwoodwackr]

That is pretty much it, I got this from a 441c thread a few years ago and I have been using this reset when changing in elevation and it has worked for me.

1. With the chain brake engaged…
Hold throttle and set start lever to Start position
Start saw and let idle in Start position for 90 seconds
Immediately move lever to Stop position
This will reset the carb to original factory setting.

2. With the chain brake engaged…
Start saw in Run position
Let idle in Run position for 90 seconds
Immediately move lever to Stop position
This will calibrate the idling characteristics of the saw.

3. With the chain brake engaged…
a. Hold throttle and set start lever to Start position
b. Start saw then Blip throttle to bring the machine to the Run position
c. Disengage chain brake and make five uniform cuts through a log.
d. This will calibrate the full throttle characteristics of the saw.

Done.

I've done it both with and without the brake engaged, I think it is just a safety thing (dont hold me to that) at the times I done it without the chain brake on, it does spin the chain.

One of my other ported m/t saws I forgot to do the reset from a 3000' elevation change, and did like your saw ran fine on cold start, set the saw down for a few minutes and it would not restart hot 15-20 pulls later no start, then I held the throttle wide open it finally popped off, I let it cool off and did the reset and it was back to normal one pull when hot.

I think I see what I did wrong...
first time start in the morning at 'start' position. saw started right up and idled normally. I didn't wait much more than a few seconds before 'blipping' the trigger which clicked the switch into 'run'

thanks gang

 

[singinwoodwackr]

From what it sounds like, the reset procedure must set the operating window within which MTronic works for a given set of variable. When these variables change significantly, the reset procedure needs performed in order to adjust that operating window. Going from sea level to 8000' elevation is a HUGE change. Quite frankly, I'm disappointed this reset procedure is required. IMHO, this should happen automatically.

or...at the very least it should be included in the owners manual!

 

[Andyshine77]

The Mtron does read elevation but the parameters from the factory were for 50:1 ratio of Ultra. It changes some of it's ability IMO when we change too many things they didn't factor in from the factory.

Anxious to see what you experience next outing.

So they didn't factor in people would run different oil?? Sorry that make no sense, and other saws like the 441 aren't having these issues, the Mtronic system or the carbs on the 661 are obviously having issues, oil ratio has nothing to do with this.

 

[Andyshine77]

From what it sounds like, the reset procedure must set the operating window within which MTronic works for a given set of variables. When these variables change significantly, the reset procedure needs performed in order to adjust that operating window. Going from sea level to 8000' elevation is a HUGE change. Quite frankly, I'm disappointed this reset procedure is required. IMHO, this should happen automatically.

If this is so the system is even more crude than we thought. Oddly we haven't seen these issues with the other Mtronic models, so something is up IMHO.

 

[Hinerman]

I really thought I wanted a 661. I think I will hold on to my 660 for awhile, maybe for life.

 

[MustangMike]

I had to reset my 362 C after it was ported, and I used the procedure you described earlier in the thread (no chain break).

I would also try 40:1 and a different oil. I think the oil and ratio you are using really change things.

My 362 has been flawless since the reset, but the highest elevation I cut at is a little over 3,000 ft.

Good luck with it, they are nice saws.

 

[2dogs]

Hey wackr! Who ported your saw, some hippie in SFO?

 

[singinwoodwackr]

Hey wackr! Who ported your saw, some hippie in SFO?

uh...sig...

 

[porsche965]

So they didn't factor in people would run different oil?? Sorry that make no sense, and other saws like the 441 aren't having these issues, the Mtronic system or the carbs on the 661 are obviously having issues, oil ratio has nothing to do with this.

Have you tested oil ratios in your 661?

 

[Andyshine77]

Have you tested oil ratios in your 661?

Does the 661 have a two cycle engine? We can do this all day if you want. If the 661 can't handle different mix "which isn't the problem" something is seriously wrong with the 661's, especially if they plan on selling them in different countries.

I was going to order a 661 but I wait until the bugs are fixed, I did the same with the Husqvarna saws, my 550 runs like a top with K2 @ 32:1

 

[mdavlee]

Maybe max flow needs to hurry up and get a kit out for these to allow more air flow. The reset may be the best bet up at higher altitude.

 

[Andyshine77]

Here's a good fix for these 661's



Remember this discussion is about chainsaws, lets not take things too seriously now.

 

[singinwoodwackr]

Maybe max flow needs to hurry up and get a kit out for these to allow more air flow. The reset may be the best bet up at higher altitude.

Yea, talked to my dealer today...have to do the reset for that much elevation change.