Stihl 066 serial number breakdown.....decomp? newer style plastic?

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Freakingstang

Doctor Freakinstein
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hey guys, just trying to figure out the age of a few of my saws.

I would like to know where the serial number started for saws with the decomp valves


I would also like to know when they went from the flat top style plastic to the newest, rounded design.

I have three older 066's that have the flat top style covers, old style tanks, and Decomps.....One is a poly flywheel and the other two are metal. Just wanting to know if the poly was a parts saw in it's former life. lol.

Here's the dates/numbers I have found so far:

1994 serial number 131067164 and later were the smaller cranks, after the red lights.

poly flwheels were on 133917066 and later models. (early 96)


Anyone know the serial number of the older metal flywheel crank units with the larger big end bearings? Supposively they were out two years before the poly flywheel/new cranks from the searching I've done.

Anyone know then the magnums quit coming with the dual port covers from the factory? I know this was an epa deal, just wondering when....

Any other important serial number changes?


Thanks
-Steve
 
Early 1994 - Thin cylinder base ( Red light etc) changed to "thick base". Base screws changed from M6x20 to M6x25


Mid 1994 - Beefed up crank - Crankshaft BIG end changed from 12 to 13 roller pins from serial number 129 588 002. At the same time, the cylinder base gasket changed to rubber coated Steel (so quit using the junk aftermarket gaskets!).


Early 1995 - OHSA (NOT EPA) forced the dicontinuation of the Dual port Magnum muffler from serial number 131 960 509. HP dropped to 7.2


Mid 1996 - decomp valve fitted on all 066 from serial number 131 960 509


Early 1996 - Poly flywheel installed and crankshaft bearing increased in size from 13.5 to 15mm from serial number 131 917 066

Early 1998 - shrouds and filter box changed from squared to "rounded " type. Limiter caps on carbs and EPA labling...


Early 2002 - Name changed from 066 to MS660.


Lot's of ignition changes and carbs over the years...
 
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Thanks Andy!

I've seen a pile of carbs over the years.

Was there that many versions of the non epa carbs? I have a small stockpile of them. Seems most of them had bigger fixed jets. I also like the metal H &L jet screws...sure beats the platic ones. lol

Thanks again
 
Was the larger fuel tank included in the 98 cover and air box revision? Meaning was there any old style air filter box setups with the larger tanks or vice versa?
 
many... and some I don't even have on my IPL's!

The old WJ were just basic "old" carbs where any "precision" adjusment was done via drilled bores and the needles. Then came the removeable jet WJ carbs and WJ carbs with mid-range or partial power jets.


Stihl changed the jet size from .64 to .62 on the magnum when they did away with the dual port. In practical terms, all they did was reduce the gas needed to maintain 1 turn out calibration... you could also have just turned the H screw in more.


If you want to undo any fuel saving and any EPA stuff, for pure grunt the old carbs are great.. but the later carbs have mid-power mixture advantages.
 
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ok, one more for the masses and I'll leave you alone. At least for tonight, lol.


When did they have clear fuel tanks put on them?

Some people say the red lights never came with them....got a couple here, and the date code on the tank matches the covers......lol
 
I don't have any of the pre 1993 tech notes at home.. I can look that up on Monday.

I've seen red lights with clear tanks, but can't say for sure if they were changed out later or not. Heck, I've put clear 066 tanks on 064's (small bore "red light with no light").
 
I'm pretty sure there was a run of Red Light saws with see-through fuel tanks. We bought two in the spring of '92 for a park service Fire Use Module and they were Red-Light models with clear tanks.
 
Early 1994 - Thin cylinder base ( Red light etc) changed to "thick base". Base screws changed from M6x20 to M6x25


Mid 1994 - Beefed up crank - Crankshaft BIG end changed from 12 to 13 roller pins from serial number 129 588 002. At the same time, the cylinder base gasket changed to rubber coated Steel (so quit using the junk aftermarket gaskets!).


Early 1995 - OHSA (NOT EPA) forced the dicontinuation of the Dual port Magnum muffler from serial number 131 960 509. HP dropped to 7.2


Mid 1996 - decomp valve fitted on all 066 from serial number 131 960 509


Early 1996 - Poly flywheel installed and crankshaft bearing increased in size from 13.5 to 15mm from serial number 131 917 066

Early 1998 - shrouds and filter box changed from squared to "rounded " type. Limiter caps on carbs and EPA labling...


Early 2002 - Name changed from 066 to MS660.


Lot's of ignition changes and carbs over the years...
Any ideal in 2002 what the serial # was that they changed the name to MS660. I have several 066 s, MS660 s that could go either way and can't read the plate on top and decal is gone from the rear handle. They have poly flywheels and the larger crankcase, but could be either on the records. The serial # start about 152 first three numbers and go to 165 as I know some are each.
 
Any ideal in 2002 what the serial # was that they changed the name to MS660. I have several 066 s, MS660 s that could go either way and can't read the plate on top and decal is gone from the rear handle. They have poly flywheels and the larger crankcase, but could be either on the records. The serial # start about 152 first three numbers and go to 165 as I know some are each.
It would be great to see Lakeside come back.
 
Early 1994 - Thin cylinder base ( Red light etc) changed to "thick base". Base screws changed from M6x20 to M6x25


Mid 1994 - Beefed up crank - Crankshaft BIG end changed from 12 to 13 roller pins from serial number 129 588 002. At the same time, the cylinder base gasket changed to rubber coated Steel (so quit using the junk aftermarket gaskets!).


Early 1995 - OHSA (NOT EPA) forced the dicontinuation of the Dual port Magnum muffler from serial number 131 960 509. HP dropped to 7.2


Mid 1996 - decomp valve fitted on all 066 from serial number 131 960 509


Early 1996 - Poly flywheel installed and crankshaft bearing increased in size from 13.5 to 15mm from serial number 131 917 066

Early 1998 - shrouds and filter box changed from squared to "rounded " type. Limiter caps on carbs and EPA labling...


Early 2002 - Name changed from 066 to MS660.


Lot's of ignition changes and carbs over the years...
So any 066 built new after 1996 would be fitted with a decomp valve correct? Sorry, I have been trying to find an answer to this for awhile. Found somebody trying to sell an MS660 without a decomp that's "from the factory." Didn't buy the story for a second. Especially because the cover has the hole for the valve. It just got me wondering about the name swap and so on.
 
So any 066 built new after 1996 would be fitted with a decomp valve correct? Sorry, I have been trying to find an answer to this for awhile. Found somebody trying to sell an MS660 without a decomp that's "from the factory." Didn't buy the story for a second. Especially because the cover has the hole for the valve. It just got me wondering about the name swap and so on.

Maybe it's got an early 066 cylinder that's way better than EPA 660? See if you can see casting numbers on the jug with the covers off?
 
Maybe it's got an early 066 cylinder that's way better than EPA 660? See if you can see casting numbers on the jug with the covers off?
Well I asked for numbers and it seems as though they have become all too busy to answer. My main worry, especially considering the price being asked of it, is that it's some knock off that they slapped plastics and decals on. My MS461 is my "big" saw and it does everything I ask of it so I don't that saw. Sometimes a guy finds an unreal deal like that and it turns out to be true. I bought that saw at my local Stihl dealer with a 28" bar, a 20" bar, and two chains a piece for $480 and the saw ran great. Just like anything I own that has engine I put some work into it to see how much power I could get from it and its still running like a new saw. Could use some cosmetics I like to think she's purty 'cause she's dirty haha
 

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