Old 066 cylinder crack

Arborist Forum

Help Support Arborist Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

AndyR

ArboristSite Operative
Joined
Nov 20, 2007
Messages
188
Reaction score
15
Location
Central Illinois
Hi-
Brand new to saws and repair here-though I've done a bit of auto engine machine/assembly work. I recently picked up this, what I believe to be an older 066. I bought this with the intention of setting it up in a Granberg mill as a complement to my recently acquired, used Ripsaw. This saw was, I think, neglected a bit. In taking it apart to clean it, I guess I got a little carried away and took it pretty much all the way down, except for the case. I was originally thinking of cleaning up the cylinder (as I've read about in numerous posts here) and giving it a new piston and rings, but in looking at the cylinder closely, there appears to be a crack. So somewhat long story short-I'm thinking I need to replace the cylinder. I guess the general consensus in the posts I've read is that OEM quality is the best. However, I'm interested in this big bore cylinder that Bailey's has listed. Seems like for a milling saw this might be a nice upgrade, but I'm wondering if the quality will be ok with these new parts. I'd be interested in hearing opinions on different aftermarket brands and where they can be purchased online. I obviously don't want to spend any more than is needed to get this saw back in order but I'm having fun and am committed now and I guess I'll spend what I have to (within reason).

This saw has no decompression valve.
Crank spins really nice and doesn't seem to have any wobble or anything, so I was planning to leave the case alone-save for external cleaning.

Would retrofitting a decomp. valve be as simple as cutting a small hole in the old plastic cover, and installing the valve in the new Cyl.? Is it worth this little extra effort and expense.

Would the stock Walbro carb be ok with the bigger cylinder. I was planning on putting it all together and taking it in to have the carb tuned properly.

Some of the wiring insulation is all worn and wiring is exposed, so I'm planning to replace that where I can, rebuild the carb., replace any hoses, filters and small parts like the starter pawls while it's apart too, but is there anything in particular that your experiences tell you I should do while this is disassembled?

I do have a 064/066 repair manual but could use a ipl if someone has one available.

I've been feeling a little bit down about it, like maybe I bought a lemon, but I am having a good time working on it and learning a ton from this site + I get bored as all hell in the winter and can't stand sitting in front of the TV for more than an hour or two at a time. I think, in the end I'll come out cheaper than a new MS660 but I'll have so much more know-how.

Thanks for any input you guys may have on the above questions.
Best,
Andy
 
old 066

Welcome, I had an issue with my 3120.Where it burned down.I went with a aftermarket piston/cylinder.The problem I encountered was the piston hitting the top of the cylinder.I tried a thicker base gasket.I ended up going with oem piston/cylinder. Everything went together fine after that.There is a difference in my opinon.As with the decompression button. You can't go wrong with that either.I did that to my 066.My arm Thanks me every time!One thing that I have learned from being here is that they reccomend that you run 32:1 mix in saws 70cc or larger.You may use a few more spark plugs.But you will use less cylinders.$$$$$
 
Hey Andy,
Welcome to AS.
I just finished an old 066 rebuild (http://www.arboristsite.com/showthread.php?t=57894&highlight=066+project)
so take a look at the thread I put up. All new STIHL cylinders for that saw will have a deco hole, so you can plug it or put one in. It really does make it easier to start. I would order a new shroud for the deco valve, but be aware that there are several different shrouds, so look carefully at your air filter cover and backing plate so that the cover and shroud match up OK.
I haven't messed with aftermarket cylinders so I can't say, but OEM will always be superior quality for the extra $$$ IMO.
 
Thanks. Looks like OEM is the best way to go. Is it best to go with a local dealer for parts or will I save much by shopping online? There a P&C set on ebay right now for $235.00 (ouch).

Thanks for your time.
Andy
 
Ouch twice — $300.

Thanks Lakeside-
That puts it in perspective for me. Ordered the OEM, ebay P&C (from chainsawguy).
Now I'm wondering if I shouldn't go ahead and do the crank bearings and seals. I've read the posts on splitting the case without the stihl tools but I'm wondering if I'm really up to the challenge. I'd hate to put it back together and have a bad seal in the crankcase somewhere and have to start all over.

How do I go about finding out what shroud will fit with my air filter cover (aluminum-which I kinda like) and backing plate?

I'll try to take and post pics as I go. Maybe that'll help some other newbies...

Thanks guys-
Andy
 
You can do the crank seals without splitting the case, if the crank bearing turn fine and there is no play in the crank I would leave that stuff alone.
 
I think you can get a BB from Baileys for around 110.Yep just checked,go to the home page ,right side bottom of the list click on STIHL aftermarket.
 
Last edited:
Thanks

Yeah, I saw the big bore kits there but was a little afraid of aftermarket parts on those. I've seen the difference a couple of thousandths of an inch can make in something like this.
I went with new oem.

I took the clutch off today. Tried the rope trick but the rope I had was compressing too much (it kept turning over) so I ended up using a scrap of vinyl cove base cut into strips. 4 stacked up and placed in the spark plug hole worked like a charm:)

I took the oil pump off and looked it over but I don't really know what I'm looking for. Plastic gear looks good, metal gear has somewhat odd shaped teeth, but they look like maybe they should be, in order to engage the pointed "threads" on the plastic gear- They're kid of tapered.

I think my clutch looks pretty good no obvious signs of wear...

Also bought some simple green pump spray cleaner/degreaser. I figured that would be kind of mild and wouldn't eat my gaskets and seals still on the case -though I do plan to apply it carefully. We'll see how that works out...It's a mess and I don't have compressed air...

Cheers and happy New Year
Till later.
Andy
 
Is this crankcase toast?

This is the original thread for the "rebuild" on this saw so I thought I would continue it here rather than start a new one. I think I've mentioned, in other 066 threads, having a problem with my dealer's service dept hanging on to my crankcase for over two monthsto replace the seals. This past weekend, two weeks after my last visit to pick up a couple of ordered parts, I went back to get it. Long story short, I picked it up and the new seals were laying in the box. The counter guy was very apologetic and said to just take them. Doing a little more cleanup this weekend I've noticed a few cracks in the case. One of them I knew about (by the bolt hole under the oiler) and I thought that looked repairable. The two cracks by the bar mounting studs, I'm not so sure about.

So I guess my first question is does this case look too far gone to you guys? My inclination is that the cracks by the studs are ok but I wouldn't mind a few opinions. I don't know if it was leaking bar oil when I got the saw-I confess I never ran it.

Otherwise I am planning to go ahead and split this open (waiting on flywheel puller from cheapstihlparts) and clean it all up so I can assess things a little better, if it looks repairable, I'll probably put new bearings in while it's apart.

If it looks to you guys like it isn't worth fooling with this case then I might be looking for a case and bearings for an aluminum flywheel model crank.

I really appreciate any help or ideas.
It's definitely one step forward-two steps back with this project.

AndyR
 
One crack too many?

I'm no expert on saw cases but would be inclined to look for a different project saw . It's one thing to replace the P&C , fuel lines ,carb kit etc but looks like you might be pouring money into a pretty deep hole . Just mho .
 
I know the itch that can burn to fix a saw up. But you might want to think seriously about acquiring another case. Those bar studs are in a high stress area. I'm not sure it will last. It may leak bar oil as well. I've got a little 015 AV case like that. It's otherwise a good saw but dumps oil all over the place if left with oil in the tank. You should be able to pick up a case pretty cheap. Just make sure you get one that had an aluminum flywheel since they use a different crank.

About the crank bearings. Clean them up realy good once they're out of the case. If they're smooth and not pitted and there's no radial play, I see no reason to replace them.
 
hey welders

rather than have a pile of un useable parts...
couldn't he have the cracks welded? seems a waste to let the saw go to parts.
i think i would have to try!
 
rather than have a pile of un useable parts...
couldn't he have the cracks welded? seems a waste to let the saw go to parts.
i think i would have to try!

Thanks guys,
I definitely want to finish this. I've got a new P&C sitting on the bench for it along with a whole slew of other parts. I don't mind buying a used case ,ebay or otherwise, if its in good shape, but I just don't want to end up with someone elses junk, like I did the first time.

I'm very fast approaching the cost of a new saw with this project. I know I did it wrong, buying such a lemon, and I've learned so much since starting with this one that I don't think I'll make that mistake again.

It just doesn't make sense to stop now...I don't know about welding though, I think I'd rather put the bucks in a good used case.

AndyR
 
just a thought really.

Thanks guys,
I definitely want to finish this. I've got a new P&C sitting on the bench for it along with a whole slew of other parts. I don't mind buying a used case ,ebay or otherwise, if its in good shape, but I just don't want to end up with someone elses junk, like I did the first time.

I'm very fast approaching the cost of a new saw with this project. I know I did it wrong, buying such a lemon, and I've learned so much since starting with this one that I don't think I'll make that mistake again.

It just doesn't make sense to stop now...I don't know about welding though, I think I'd rather put the bucks in a good used case.

AndyR

my suggestion was really more of a question.

i have a dewalt chopsaw that had a crack in the table from someone (not me) adjusting angles on it with a hammer!!!
saw cost $300.00. the welding was $18.00 at my local marine/fabricator guy.

chopsaw ain't broke again yet....
but it isn't a vibrating, thermally expanding, 13,000 rpm chainsaw either!:)
 
Bearings... Once clean the only way to figure out if they are galled or worm in to put some axial load on them. Squeeze them lightly in vice and turn the inner core.. if they are rough or rachetey, they are toast.


Case... Just get another...
 
Thanks for all of your input.

I suppose having cracks in the part of the saw responsible for holding the bar and chain could be a little worrisome.

As to the welding, I suppose it could work, but I've heard that Mag. can be tricky. I also don't want to go through putting it all back together and have a weld break loose...

So, I'll start the search for a good used case (for aluminum flywheel). If anyone has any leads, I'm all ears. I'm kind of scared most of the stuff on ebay and would rather buy from one of you guys. Feel free to PM me if something turns up.
 
So, I'll start the search for a good used case (for aluminum flywheel). If anyone has any leads, I'm all ears. I'm kind of scared most of the stuff on ebay and would rather buy from one of you guys. Feel free to PM me if something turns up.

Contact cheapstihlparts, Bryce, on eBay. He'll likely have what you need. One more thing. You cannot replace just half of the case. They are machined as a matching set. Bryce will likely sell you a case with a crank and good bearings.
 

Latest posts

Back
Top