STIHL MS 066 REPAIR HELP ME OUT

[Cooper264]

Im going to do some playing around with it on my next day off, If i can get it running with the OEM coil, ill fix the wires on the red light part and put them in the new FT handle.

After that ill post er for sale.

Ill have to get some pics here soon

 

[Cooper264]

Something that ive always wanted to do with an old stihl is paint the case. Does anyone know what type of paint is close to the OEM in quality, durability, and finish.

 

[lehman live edge slab]

All the farmertec stuff will not match up or fit on an old flat top short case red light. If you have all the original parts best to put it back together and find and oem tank for it. If you decide you want it gone and will sell for a reasonable price I have a red light here the lower rod bearing let go on but that rest of the saw is good.

 

[Vintage Engine Repairs]

Like others have said, put every OEM piece back on that saw. Grab a used OEM tank and used OEM chain brake parts that are missing and then problem solve things by testing, not by guessing. Put a new OEM carby kit in and test all the passages with cleaner for flow. Check needle height and for sealing / bleeding.

You can’t tell if crankshaft seals are good by looking at them, for a start the seal surface is a dust seal not an atmosphere seal, that’s underneath it and they need vacuum to be tested.

Wires that looked messed up, test their continuity, replace them or put heat shrink tubing over the damage and re test, test the coils primary and secondary windings too.

Changing coils or flywheels from different models will require you to test spark timing with a timing light and degree wheel, both the idle timing and spark advance timing - the manual will confirm it what rpm ranges are required.

No don’t paint it, unless you are going to strip it all, fill all the imperfections, sand it, and have it professionally powder coated, it will look really cheap and further devalue the saw.

You had good intentions to help your mate out, but all you’re doing is quickly turning your mates desirable saw into something with no value and making more problems for yourself.

 

[Cooper264]

Alright so I got to playing with the ole gal this evening. Put on the old coil with new wires...Got spark and fire. Repaired the old wires and slapped them on...Got spark and fire.

I now have a running saw. Its having some carb issues that im going to have to work out but other than that shes good. I think the bulb in the light may be burnt out so i'll look into that.


On a side note, I know that this is a very desirable saw all oem, but I would rather replace certain things with cheap and available FT than trying to find high priced, used stihl parts... I dont have an air filter cover, it was crushed,, so With the new style tank on it the FT is the best way for me to go. Im just not the guy to spend the time or money trying to find an OEM tank.. If I were to run across a cheap Air filter cover in decent condition, I could go through the process of changing the filter shroud, but then I run into problems with the angle of the original carb placement and the new style trigger assembly.

The clutch break, I dont think there is a thing wrong with the FT ones, it was missing the break handle as well so it all works out there.

I do definitely want to switch the chain tensioner back to OEM, the only parts that were missing there was the hardware that keeps it in the saw. Both screw gears and pin are still there

I was contemplating sand blasting the case and powder coating it, but it looks pretty good as is.

Conclusion- Everything is oem now and working except chain tensioner, tank, filter cover, brake handle and brake parts

 

[Cooper264]

Correction, new clutch drum. The old's bearing seat was washed out and it wobbled back and forth a good bit.

 

[RedFir Down]

I just bought a square top 066 filter cover from my dealer for around $35.
I say fix it right.... the old saw deserves it.

Sent from my SM-G970U using Tapatalk

 

[Vintage Engine Repairs]

I appreciate searching for used OEM requires effort and time - I have had to wait months for parts to arrive, but it’s worth it for the exact reasons you see now, the AM parts will only cause you trouble and to chase your tail. That and because of desirability, resale value and reliability

 

[Cooper264]

Waiting on the rebuild to come in for the walboro carb, threw on a ft just to see if she'd run right. Ran great after a little bit of screw turning. Red light thingy mabob works, drilled a 3/8 hole in the FT handle shroud, notched out some holes on the side and the light popped right in nice and tight. Waiting on the tac to come in so i can give er a proper tune. I'm going to throw on a bar and chain and do some cutting. Might run a leak down test. Might not. Just depends on how she does in the cut

 

[Wood Doctor]

So, Cooper, when you try to start it cold and raise the switch shaft from Choke to Fast idle, it does hold the Fast Idle position without dropping down to idle as it would in the Run position? Is that correct and you have checked it out?

 

[Cooper264]

So, Cooper, when you try to start it cold and raise the switch shaft from Choke to Fast idle, it does hold the Fast Idle position without dropping down to idle as it would in the Run position? Is that correct and you have checked it out?

Yes. From a cold start, fires on choke, runs on fast idle... at a fast idle. and puts as it should on normal idle.

Something I have learned from all of this- I have built dozens of the FT 660 kits,,, and this worn out old hunk of junk runs better than any of the FT ones I've put together. I'm blown away by how this saw feels compared to aftermarket. I haven't had it in wood, but I have a feeling its going to do great.

I need a little help with the red light coil. At what point does it limit the saw? and how does it limit it? Does it quit sending spark to the plug or does it just light up the light and hope that you'll let off the throttle? And where could I possibly find a NOS coil that doesn't cost an arm and a leg? The red light hicky is pretty cool

 

[lehman live edge slab]

Waiting on the rebuild to come in for the walboro carb, threw on a ft just to see if she'd run right. Ran great after a little bit of screw turning. Red light thingy mabob works, drilled a 3/8 hole in the FT handle shroud, notched out some holes on the side and the light popped right in nice and tight. Waiting on the tac to come in so i can give er a proper tune. I'm going to throw on a bar and chain and do some cutting. Might run a leak down test. Might not. Just depends on how she does in the cut

That was the point or the red light on those saws, it’s used to tune the saw to the right rpm. If I remember right it will be on steady then as you lean it out the light will start to flash when you get to that point back the high out 1/8-1/4 turn and done.

 

[markds2]

That was the point or the red light on those saws, it’s used to tune the saw to the right rpm. If I remember right it will be on steady then as you lean it out the light will start to flash when you get to that point back the high out 1/8-1/4 turn and done.

Not exactly Sir, I understand from what I have read is that the Red light comes on at around 12,000rpm and the coil is limited at 13,500. You can see from the pic below that you lean the saw down with 1/2 a turn clockwise on the H screw when the light comes on. The coils were notoriously unreliable and you can read the trials and tribulations I had with mine here: https://opeforum.com/threads/treemonkey-red-light-066-build.22196/

I eventually ditched the RL coil and installed a unlimited coil.

 

[Cooper264]

Not exactly Sir, I understand from what I have read is that the Red light comes on at around 12,000rpm and the coil is limited at 13,500. You can see from the pic below that you lean the saw down with 1/2 a turn clockwise on the H screw when the light comes on. The coils were notoriously unreliable and you can read the trials and tribulations I had with mine here: https://opeforum.com/threads/treemonkey-red-light-066-build.22196/

I eventually ditched the RL coil and installed a unlimited coil.
View attachment 280529

Thats what I was originally thinking. Ill check er out when my tach finaly comes in. Did you find anywhere that you could buy one of the original coils?

 

[markds2]

Thats what I was originally thinking. Ill check er out when my tach finaly comes in. Did you find anywhere that you could buy one of the original coils?

I happened to have a later model decomp flat top 066 in bits here at the time, it had an unlimited coil and the correct dual keyway aluminium flywheel to go with it, I just swapped them over and the saw was a different animal altogether. The Red Light doesn't work any more but I'm OK with that, I always tune by ear and then confirm with a tach so the feature was redundant anyway.

 

[Vintage Engine Repairs]

Something I have learned from all of this- I have built dozens of the FT 660 kits,,, and this worn out old hunk of junk runs better than any of the FT ones I've put together. I'm blown away by how this saw feels compared to aftermarket. I haven't had it in wood, but I have a feeling its going to do great.

This is why many of us have been saying keep it all OEM and slow down. Search for NOS and stay away from AM parts - a little effort in searching and a little
waiting will be worth it . You can lead a horse to water but can’t make It drink so to speak.

It’s not surprising, you are comparing one of the finest saws from the number 1 selling chainsaw manufacturer in the world, from Germany. Every little aspect has been gone over meticulously. Compared to a saw made by people who couldn’t care less if it even runs or not using the lowest quality parts and massive tolerances.

 

[Cooper264]

For anyone thats still interested. I got the saw all back together and running as she should. It runs pretty damn well in my opinion. The guy I was looking at it for originally wanted me to sell it on ebay for parts or fix it and then sell it and split the profit. In the end by our math minus ebay fees and shipping and parts, I gave him $200 and he was tickled to death. He's a pretty good friend of mine and already has a nice 660 so it all worked out great. Im going to use this as my personal saw, so I ended up putting an aftermarket west coast side cover, set of dogs, and full wrap handle on it (all the OEM parts will be going on a shelf for safe keeping). All and all, this is a very nice saw and does exactly what I need. Without this forum I would have spent a LONG time trying to figure out the flywheel coil thing. Many thanks to everyone who helped out

 

[RedFir Down]

For anyone thats still interested. I got the saw all back together and running as she should. It runs pretty damn well in my opinion. The guy I was looking at it for originally wanted me to sell it on ebay for parts or fix it and then sell it and split the profit. In the end by our math minus ebay fees and shipping and parts, I gave him $200 and he was tickled to death. He's a pretty good friend of mine and already has a nice 660 so it all worked out great. Im going to use this as my personal saw, so I ended up putting an aftermarket west coast side cover, set of dogs, and full wrap handle on it (all the OEM parts will be going on a shelf for safe keeping). All and all, this is a very nice saw and does exactly what I need. Without this forum I would have spent a LONG time trying to figure out the flywheel coil thing. Many thanks to everyone who helped out

Awesome! Glad to hear of the outcome!