Saw run with no oil..

[Jibber]

Hi, first post, although I have been a visitor for years. I usually find answers to my questions in the search mode.

I did one of those "I'm never going to do that" mistakes. Ran a can out of gas mix then filled it up and neglected to put the oil in.

I suspected something was wrong when the saw, (Stihl 039) would start but only run for about 15 seconds before stopping. I did this about 3 or 4 times not figuring out what was going on. I returned home (I was at a neighbors taking apart a tree) to get another saw and noticed the still unopened bottle of oil near my barn. Duh.

I mixed the fuel.. emptied what was in the saw and replaced with the mix and she fired right up and seemed no worse for wear. At least I don't hear any noises, revs seem fine. Power seems good.

Now, yesterday, I was at the local dealer buying an arborists MS 200T and told my dealer the story.. He responded "I'll bet that was expensive". He seemed suprised that it has not totally seized and says I probably at least scored the piston. But, it really does run pretty good. Oh, it'll bog down on the big stuff, but it did that before. I usually use the 460 for the big stuff anyway.

my question.. What are the chances I escaped harm? And, how can I tell if I did something I should fix?

Now, this is an 039, but it really has very little use on it.. maybe 4 or 5 tanks of gas total. So, it's well worth a fix even if it is a more expensive fix.

thanx for any help.

 

[oldsaw]

pull the muffler and take a look at the piston and cylinder. If you see scratches in the piston and cylinder wall, the dealer is right. If not, or they aren't bad and the saw still runs well, consider yourself one of the luckiest guys in town. Go buy a lottery ticket, it's your day.

Mark

 

[GASoline71]

Pull the muffler off and check the piston for scoring. Then move the piston down with the flywheel and shine a light through the sparkplug hole. Look at the cylinder walls to see if they are scored. You might have got a way with it.

I have a buddy that did the same thing to a Husqvarna 359 some years ago. He never checked the piston and cylinder at all. Just put some fresh premix in it and has run it that way ever since with no problems.

I would check it out if I were you, just to be safe.

Gary

 

[bump_r]

WElcome aboard, good to see you searched, and sorry about your "duh" moment (we all have those, BTW).

Pull the muffler and slowly turn the saw over - you can see the exhaust side of the piston then the intake side of the cylinder. That should give you a pretty good idea of damage.

Does it idle well? If so, I'd tend to think you skirted disaster and MAY be OK. Not entirely likely, but stranger things have happend.

Oh, trade it in on a Dolmar 5100s - I hear those things are GREAT!

 

[Jibber]

Will pull the muffler and let you know what I see. It does idle fine.

 

[Jibber]

Well, I got it on the bench and pulled the muffler. It IS scored pretty bad both the piston and cylinder walls. Guess it's off to the shop for some expensive work.

Thanks for the advice!

 

[GASoline71]

Are you handy with tools and mechanically inclined? Changing a Piston and Cylinder is a pretty straight forward job. It ain't rocket science... give it a shot!

Gary

 

[bump_r]

Are you handy with tools and mechanically inclined? Changing a Piston and Cylinder is a pretty straight forward job. It ain't rocket science... give it a shot!

Gary

YES! I guess this saw's not the easiest to work on, but patience should get you a good way down the road.

Someone just did a P/C change on a 390, search for the thread - good pics if I recall correctly.

 

[Timberhauler]

I once ran a whole tank full of un-mixed gas through a 044...I guess the pre-mix that was left behind in the crankcase was good stuff as there was no damage,and the saw ran good,everyday,for about another year

 

[Jibber]

Well, I'll look for those pics because they want 250 bucks for the cylinder alone. By the time they figure in labor and the piston I'm looking at the price of a new 390. Why do they do that? Make the parts so expensive you can't fix the things.. doesn't make sense to me.

If I can't fix it myself I'll just use it. It has enough power to go through most anything a 20" bar can handle.. It does seem to stall the chain on the big stuff.. but seems to run pretty good for an engine with a grooved up piston!

of course, I could use this as an excuse to get another mid range saw.. that 361 sure looks inviting.

anyway

Thanks for your help.

 

[troutfisher]

maybe just a piston kit.....check out this thread
http://www.arboristsite.com/showthread.php?t=44235&highlight=scored+cylinder

 

[ChuckinOhio]

How much is too much?

Scoring that is.
I recently peeked in the exhaust port of a friends 029 when he had it off to open it up, and there was maybe 3 light score marks on the cylinder wall and when you ran the piston up past the exhaust port it was very lightly marked in one place. None of these spots was very deep, it took a sharp probe to detect the difference despite being visible.

Problem or no? Saw still seems to run really good and responded well to carb adjustments.

Chuck

 

[troutfisher]

Scoring that is.
I recently peeked in the exhaust port of a friends 029 when he had it off to open it up, and there was maybe 3 light score marks on the cylinder wall and when you ran the piston up past the exhaust port it was very lightly marked in one place. None of these spots was very deep, it took a sharp probe to detect the difference despite being visible.

Problem or no? Saw still seems to run really good and responded well to carb adjustments.

Chuck

That doesn't sound like a big deal, make sure the air filter is clean. If dirt was the cause you don't want any more.

 

[Luke]

I recently bought an 066 that was locked up to the point I almost could not get the jug off. Basically the piston had welded itself to the bore. Big junks of aluminum were stuck to the cyl wall and appeared to have major scoring. Since the BB Baily stuff is not available I went to the local Stihl dealer to order a top end. After hearing the price of $340 for the kit and $155 for only the piston I got real serious about trying to save the jug. There are many threads on the subject, but I used a flapper wheel from a head porting kit with wd40 as a lube. In less than an hour of total time I had a jug that even the Stihl service guy said looked very good. Be carefull around the ports though, as the are chamfered with exposed aluminum. I cut mine a little but its ok. In summary I would work on it a little and not just assume its trash.

On Stihl prices. I recently had a custom set of JE racing pistons made for a SB Ford stroker. Total price was much less than TWO off the shelf, cast Stihl pistons. I'm guessing that you could buy BMW or Mercedes pistons for less, might be wrong though. How much in sales are they loosing to the aftermarket? I'm guessing everyone in their supply chain could still make nice money at lower prices. They probably think they are pushing sales to new saws, but how many ppl are like me and mentally record this as another reason not to buy a new Stihl saw?

 

[Ray Bennett]

Well, I'll look for those pics because they want 250 bucks for the cylinder alone. By the time they figure in labor and the piston I'm looking at the price of a new 390. Why do they do that? Make the parts so expensive you can't fix the things.. doesn't make sense to me.

If I can't fix it myself I'll just use it. It has enough power to go through most anything a 20" bar can handle.. It does seem to stall the chain on the big stuff.. but seems to run pretty good for an engine with a grooved up piston!

of course, I could use this as an excuse to get another mid range saw.. that 361 sure looks inviting.

anyway

Thanks for your help.

Stihl parts are expensive, I think they do that so they will get to sell another saw. They do not make money if a mom and pop shop fixes your saw.

Call Baileys before you buy a new jug and piston, I recently priced the 039 there for 200 but im gona look for an after market one, I always see them for the 029 for 80 bucks so someone must make an after market piston and jug for the 039 but I have not found it yet. But before you order one tear your saw down, Very easy to do, just be patient. The jug may only need honed then you will just need a piston. You would be surprised what a good machine shop can fix. Hope this helps.

 

[Beast12]

Well, I have a story for you to set your mind at ease.

About 8 years ago my Dad went out and bought 2 brand new 066s. We took them out to our first job. Each of them had barely any gas in them (just enough for the dealer to test and set them up). My brother goes and gets the gas can and fills them up (as well as about 5 other saws).

My Dad takes one of them (066) and walks over to a tree and puts a notch in it. He does his back cut and the tree comes down. Then he begins to cut the stump off. About half way into the stump his saw shuts off (10+ minutes since he STARTED cutting the tree down). He tries to start it back up and no go.

He looks at the gas tank. The gas looks kind of yellow, not the bluish tint that the mixing oil gives it. Turns out my brother put straight gas in all the saws. So, we dump the gas out of all of them (into the brush chipper) and refill them with mixed gas.

My Dad tries to fire up the saw and it starts no problem. Both 066s have been used equally since then. I have NO idea what one of the two was used on it's first day on the job with straight gas.

-Matt

 

[dtnodya]

I recently fixed my stepdads MAC 130 ... After I got everything put back together and was super excited to see if it ran, I pick up the small gas can (since I mix my oil in a small can) ... Well, I put the gas in and it looked yellowish but I wasn't even thinking about that at the time. Cranked it up, it ran strong for about 15 seconds and then cut off and smoke came out of the spark plug hole. I knew immediately what probably happened .. WRONG SMALL GAS CAN! So I check and sure enough it was regular gas. So I emptied it, looked at the piston and it looked fine, put in some mixed gas and after like 30 pulls it fired. It has run perfect since .. better than when it was new my stepdad says. I felt so stupid though and you definitely aren't alone ..

 

[Stihl #1]

Well, I'll look for those pics because they want 250 bucks for the cylinder alone. By the time they figure in labor and the piston I'm looking at the price of a new 390. Why do they do that? Make the parts so expensive you can't fix the things.. doesn't make sense to me.

Hey Jibber,
Sorry about the trouble, but stuff happens. I am sure someone has posted this before, but to refresh the topic, the MS 170, 180, 270, 280, 290, 390 models are what is known as modular engine designs. This means that the crank is held in the cylinder by an engine pan, instead of a split case plus cylinder. The engine "module" now has all the rest of the saw bolted to it, so of course this means the reverse to get to the piston, so more labor for repair. Stihl considers this a homeowner or occasional user type of saw. The MS 260, 360, 361, 440, 660, and 880 are considered pro saws, with the split magnesium case and a 4 bolt cylinder, so in most cases the piston can be in your hand in 5 to 10 minutes.
The reason for all this is selling price. It costs more to build the saw to the pro level, so the modular design was a way to build a good saw that could be sold for less money. Compare a MS 390 with a MS 361, and the 361 has more power, less displacement, and less weight, at a cost of around $120 more, so the purchaser can make a choice. Stihl has more models than most any other manufacturer so that the dealer can have a broad selection, and hopefully make a little effort to qualify the customer as to which saw would best meet his needs at a price he can afford. If you choose to save some money when you buy it, it may cost more, or not be worth fixing later, because it is less expensive to make a modular saw than a pro saw.
If you decide to tear it down, clean up the cylinder with a fine flapper wheel and lots of lube, as mentioned earlier, or if there is a lot of aluminum on the cylinder wall, try to very carefully get it off with some muriatic acid, as mentioned in a post here a week or so ago. Don't let it get on the al, and remember that the Nikasil is very thin on that cylinder, so don't get to aggressive trying to sand or hone it clean. If it the coating is OK, a new piston will probably allow you to run the saw. Usually unmixed fuel doesn't hurt the crank.
Good luck.

 

[RiverRat2]

maybe just a piston kit.....check out this thread
http://www.arboristsite.com/showthread.php?t=44235&highlight=scored+cylinder

I think the Trout fisher's is spot on,,,,,Since the saw is till running You might be ahead to pull it down, have the cylinder honed lightly to clean it up get a piston kit,,,,,,,, put it back together and you may get a few more years out of it,,,,, I will almost guarantee if you continue to run it as it is,,,,,,

Toast............................... :deadhorse:

 

[GASoline71]

Hey Jibber,
Sorry about the trouble, but stuff happens. I am sure someone has posted this before, but to refresh the topic, the MS 170, 180, 270, 280, 290, 390 models are what is known as modular engine designs. This means that the crank is held in the cylinder by an engine pan, instead of a split case plus cylinder. The engine "module" now has all the rest of the saw bolted to it, so of course this means the reverse to get to the piston, so more labor for repair. Stihl considers this a homeowner or occasional user type of saw. The MS 260, 360, 361, 440, 660, and 880 are considered pro saws, with the split magnesium case and a 4 bolt cylinder, so in most cases the piston can be in your hand in 5 to 10 minutes.
The reason for all this is selling price. It costs more to build the saw to the pro level, so the modular design was a way to build a good saw that could be sold for less money. Compare a MS 390 with a MS 361, and the 361 has more power, less displacement, and less weight, at a cost of around $120 more, so the purchaser can make a choice. Stihl has more models than most any other manufacturer so that the dealer can have a broad selection, and hopefully make a little effort to qualify the customer as to which saw would best meet his needs at a price he can afford. If you choose to save some money when you buy it, it may cost more, or not be worth fixing later, because it is less expensive to make a modular saw than a pro saw.
If you decide to tear it down, clean up the cylinder with a fine flapper wheel and lots of lube, as mentioned earlier, or if there is a lot of aluminum on the cylinder wall, try to very carefully get it off with some muriatic acid, as mentioned in a post here a week or so ago. Don't let it get on the al, and remember that the Nikasil is very thin on that cylinder, so don't get to aggressive trying to sand or hone it clean. If it the coating is OK, a new piston will probably allow you to run the saw. Usually unmixed fuel doesn't hurt the crank.
Good luck.

Good post.

However... If you really wanna try to do this yourself. Check ebay for a P&C. Also check with CBaileyGB's on here... he is a sponsor. Not Bailey's the retail/mailorder store... but CBaileyGB's.

Gary