ms 660

[sotc]

so i used my 660 the other day and it ran like a champ. i bought it a year ago this week. the guys were using it and it ran out of gas, they fueled it up and couldnt get it going. when i got there i assumed they flooded it so i went to crank it up and the "compression" seemed high. i pushed the compression release and it didnt get better:O so i just pulled the plug and it looks good through the hole but still hard to pull over. any ideas? it reeally has low hours

[Skwerl]

Sounds like it got hot and seized up. I'd pull the muffler and inspect the piston.

[No_Bivy]

yep....or broken wrist pin off the piston or something....that sucks.

[Skwerl]

It's probably junk, I'll take it off your hands for ya, Willie. I'll even pay shipping! :P

[No_Bivy]

Treehouse giveaway?:lol:

[sotc]

thanks brian, ill pack it up tommorrow:lol:
guess ill pull the muffler, it was working but shoot it shouldent get that hot:dur:

[squisher]

If they were running it hard and then ran it right out of gas.......running your saw lean on that last bit of gas is not a good thing to do.

[sotc]

the old 046 gets that treatment all the time and she was still pulling this afternoon. guess ill have to take care of the dainty ms's

[squisher]

I dunno for sure but my 660 isn't a real screamer those crazy rpm's near the end of a tank I would think would be a little harder on it than a 46.

And it's still not a good thing to do to a saw!!:what:



:D

[Al Smith]

If the thing was running lighter oil mix and running hot,running them out of gas is not good at all .

Pull the muffler,take a peek .If it's galled don't panic ,it can be saved for not much money .[usually]

[Frans]

I try to avoid running the saw on fumes. If you stop when it gets to that point, it is also easier to start again.

[sotc]

And it's still not a good thing to do to a saw!!:what:

:D

im an abuser:D actually i usually shut her down when i hear it suck air for the reason frans mentioned. sometime though ill try and finish that last cut:)

[fishhuntcutwood]

If they were running it hard and then ran it right out of gas.......running your saw lean on that last bit of gas is not a good thing to do.


I dunno for sure but my 660 isn't a real screamer those crazy rpm's near the end of a tank I would think would be a little harder on it than a 46.

And it's still not a good thing to do to a saw!!:what:


My first thoughts when you mentioned it was run out of gas.

[GASoline71]

Yep... a sawyer has to know that when they have been runnin' the thing for a couple of hours, and it starts to come up in RPM's they are runnin' out of gas and must shut it down.

Runnin' a saw lean until it shut off (runs out of gas) is not good at all... I wouldn't be suprised that you will see a little piston damage when you pull the muffler.

Gary

[sotc]

actually looked pretty good in there. must be the wrist pin. guess ill have to tear it down. talked to the guys this am about running the saws clear out and the said they actually threw a chain, didnt run it clear out. so thats throwing me for a loop. ill take pics when i break it open

[squisher]

Good luck with it Willie that's an expensive saw to go down with low tanks on it.

[Frans]

That is a big hit to take on a saw. Sorry to hear it.

[sotc]

one of the down sides i guess, i do love that saw!

[stehansen]

I like mine too.

[Al Smith]

actually looked pretty good in there. must be the wrist pin. guess ill have to tear it down. talked to the guys this am about running the saws clear out and the said they actually threw a chain, didnt run it clear out. so thats throwing me for a loop. ill take pics when i break it open I doubt you scewed up a wrist pin. If you pulled some aluminum on the piston just clean out the bore,shine the piston, new rings ,off to the races .Those damned pistons don't have to be as perfect as most would think .Once the new rings get seated you most likely won't be able to tell the difference . With that statement 10,000 Stihl dealers have placed a price on my head,no doubt .;)

[sotc]

haha, ill see soon, thanks:D

[JohnB]

So if I'm going to put a saw on the shelf for a while like an 038, should I run it out gas or just dump the gas out?

[MasterBlaster]

Both, AFAIK.

[squisher]

Yup dump the gas and run the carb dry.8)

[sotc]

whats the difference? running it out cold at i idle i assume?

[sotc]

well it looks good in there, still has cross hatch down low:|: with the cylinder off it turns over nicely. i feel like putting it back together but thought id ask if i should do anything or replace anything while im in there? the 5th shot seems like a funny spot by the port. hard to get good photos inside there

[Skwerl]

Is that a nick on the edge of the exhaust port?

[Al Smith]

Only a suggestion but clean all the dust off that saw before you disect it in the future .Dirt inside of an engine can be your worst nightmare .:O

By the looks of the top of the piston and ex port that thing is running plenty rich enough,maybe too much so .It may have a snag in the corner of the ex port .Check the ring for a like mark on it .

If the ring is chipped replace them,sand out that mark a little and put -er back together .

[sotc]

thanks al, i blew her of before i tore it down but the cracks were dirty:dur: the rings had a shiny spot but ill look again for cracks. gaps go on opposite sides or 90 degrees? should i do anything to the ports that is easy while im in it?

[Al Smith]

thanks al, i blew her of before i tore it down but the cracks were dirty:dur: the rings had a shiny spot but ill look again for cracks. gaps go on opposite sides or 90 degrees? should i do anything to the ports that is easy while im in it? The port work is up to you . An 066/ms 660 has enough go -get -em already without doing a thing to it . My suggestion if you've never done port work to a saw is leave it alone. Practice on a more inexpensive saw first before you get to tinkering with one that costs over a thousand bucks to replace .

Now ,if you question those rings,replace them.They aren't that costly to buy .

[sotc]

thank ya sir

[sawinredneck]

Maybe it's just the lighting, but I am seeing a mark on the piston intake side on the right as well Willie. That might be worth looking at.
The nick on the exh. side is noteworthy and might be you're hangup as others said.
If you eally want to, and feel comfortable you can widen and smooth the ports, that will gain a bit more tourqe, but I wouldn't recomend going crazy with them. Al nailed this one, it's an expensive saw to learn on!!
All in all, I don't see anything terribly wrong with it.

[will]

Me and my dad blew up two husqvarna 3120xp saws in half an hour from brand new last year. My old man mixed the fuel with outboard two stroke oil. I feel your pain!

[MasterBlaster]

Two of them?

[will]

Two of them?

Yep, first tank of fuel. we milled the most expensive timber in the world that day!

[sotc]

running again, im gonna go run the tar out of it this afternoon

[Al Smith]

running again, im gonna go run the tar out of it this afternoon Fine and dandy but what caused it to hang up???

[Skwerl]

Earlier this week all my saws started running lean and hot. I haven't done anything different, but the gas pumps at Sam's (where I've been fueling up for the last 2 months) now have the '10% ethanol' stickers on them. After figuring it out, I grabbed a spare 5 gallon can and went and got good gas at the Mobil this morning for mix gas. The saws are back to normal, not overheating and not stalling out at an idle after running hard.

If you're running ethanol fuel, you need to tune your saws for it and not swap back and forth between ethanol fuel and non ethanol fuel. They burn at different rates and you WILL kill your saws.

[stehansen]

I used outboard 2-cycle mix for years cuz I didn't know any better Will, and didn't seem to have any more trouble with my saws than I have now. Good luck with you saw Willie.

[rumination]

Brian, when they switched all the gas in Hawaii to E10 the local saw dealer convinced me to switch to a new 2-cycle mix called Opti-2 Enviro Mix. He claimed that it was formulated to run with ethanol fuel. I never did any research on it, but the saws seemed to run with no problems when I started using it.

Of course, using non-ethanol fuel is preferential, but we didn't have that choice in Hawaii.

[Skwerl]

Yup, I used to run Optimol 25 years ago when it was still new. I never ran it at 100-1 but it's a very good mix oil and works perfectly at normal mix ratios.

My point was that ethanol fuel and non ethanol fuel burn at different rates. If you're going to run ethanol fuel, then tune your saws for it and only use ethanol fuel. Otherwise, avoid it. Don't swap back and forth between them or you will burn up saws.

[sawinredneck]

I am to the point I buy the highest octane rated fuel I can for my saws. It seems the higher the octane the lower the Ethanol.
I honestly don't mind running Ethanol in my cars, but it's hell on saws.

[sotc]

dont know why it hung up, the rings looked fine so i polished it up a bit and ran it a couple hours yesterdayn all day today, running great

[will]

I used outboard 2-cycle mix for years cuz I didn't know any better Will, and didn't seem to have any more trouble with my saws than I have now. Good luck with you saw Willie.

The old mans eye sight isnt the best,he might have mixed it wrong too.