661 question of the day !!!

[angelo c]

That's because the solenoid is bad and flooding it out. It's really a simple system......

That means 2 solenoids are bad and flooding. Symptoms stayed with saw for both black and white solenoid. May very well be. Dont have a known good solenoid yet to confirm.

 

[Redfin]

That doesnt explain the wfo at wot Angelo.

Have you cracked open the carb?

 

[Mastermind]

In my experience.....on all these M-Tronic saws. If the saw will not run for 30...or 90 seconds (depends on the system which is applicable) with the control lever on full choke without choking down and dying.....then it has a bad solenoid.

 

[Mastermind]

Have you cracked open the carb?

That brings us to another excellent point. These are still carburetors. They can have bad diaphragms, be full of trash, and have needle and seat sealing issues just like any other carb.

 

[Moparmyway]

That means 2 solenoids are bad and flooding. Symptoms stayed with saw for both black and white solenoid. May very well be. Dont have a known good solenoid yet to confirm.

Say the word bud.........I’ve got a few and will send it overnight tomorrow

 

[angelo c]

Say the word bud.........I’ve got a few and will send it overnight tomorrow
View attachment 196158

Good to have friends... waiting on a pair or I'd take that offer.

 

[angelo c]

That doesnt explain the wfo at wot Angelo.

Have you cracked open the carb?

Swapped two so far. Same results. Did NOT open one yet....

 

[angelo c]

R

In my experience.....on all these M-Tronic saws. If the saw will not run for 30...or 90 seconds (depends on the system which is applicable) with the control lever on full choke without choking down and dying.....then it has a bad solenoid.

Randy. It's been my experience as well (in a much more limited sample size fo sho). I've kept a few black ones on hand for that very reason. Got caught in the want for the "new" solenoid and the "repair kits" dilemma.

 

[angelo c]

So to add a bit more background info. The saw came to me running but with a warbled out muffler mounts. Had steve (lone wolf) retap the threads and mounted the jug back up. Saw did not display this issue prior to "thread repair". That's all I know about its history. The "donor" white solenoid saw came in with piston skirt hammering in to cyl wall.

 

[Moparmyway]

The "donor" white solenoid saw came in with piston skirt hammering in to cyl wall.

Every single 661 I’ve ever opened has this “thing” happening

 

[angelo c]

Every single 661 I’ve ever opened has this “thing” happening

Sonofa...... beach....sheet.....
Here I been cussin out this crew for no reason.... maybe I should apologize?.... naw...its ALWAYS operator error!!!

 

[Redfin]

Every single 661 I’ve ever opened has this “thing” happening

They look like that brand new from dealer.

 

[RI Chevy]

Are they designed like that? With piston slap?

 

[Mastermind]

Are they designed like that? With piston slap?

The 390....395....etc. Almost all bigger saws have intake skirt wear new outta the box. Nothing unusual.

 

[RI Chevy]

Aluminum on aluminum. I guess its OK...

 

[Mastermind]

Aluminum on aluminum. I guess its OK...

Aluminum on plating. But if there's a proper oil film.....no contact. The intake port is wide.....and that means only a small portion of the piston skirt is supported during the stroke. On the down stroke it evidently bulges into the port just enough to cause it to make contact with the floor of the port as it nears the bottom of it's travel.

 

[RI Chevy]

TY for the explanation.

 

[Redfin]

So to add a bit more background info. The saw came to me running but with a warbled out muffler mounts. Had steve (lone wolf) retap the threads and mounted the jug back up. Saw did not display this issue prior to "thread repair". That's all I know about its history. The "donor" white solenoid saw came in with piston skirt hammering in to cyl wall.

Gots to ask after seeing this little tid bit. Did you pressure test after jug bolted back down?

Impulse?

 

[angelo c]

Gots to ask after seeing this little tid bit. Did you pressure test after jug bolted back down?

Impulse?

Checked....looking for base leaks more then impulse/manifold/seals leaks. (Meaning I didn't "tug " at them while under pressure checking for problems that weren't there prior....)

 

[Dub11]

Aluminum on plating. But if there's a proper oil film.....no contact. The intake port is wide.....and that means only a small portion of the piston skirt is supported during the stroke. On the down stroke it evidently bulges into the port just enough to cause it to make contact with the floor of the port as it nears the bottom of it's travel.

So all new big saws need a little massaging from the get go?