how modified is this 066?

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lumberjackchef

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Does anyone out there know the timing figures on a stock 066?

Here's the story behind why I am asking this question. This may be a little long but bear with me.

About 1 year ago I purchased my 066 off of ebay for 575.00 w/ .404 30" b/c and when I received it the owner had neglected to tell me that there were about 1/3 of the cylinder fins missing. So I emailed him to ask why he failed to mention that in the listing and ask him if he had another cylinder. He told me that he had put new rings in it and whoever had owned it before modified it and that it was quality work. And if I were to replace the cylinder it would not be nearly as powerful of a saw without modifying the new one too. He also told me that the missing fins did not affect the reliability of the saw. So far he has been right. It has always been a screamer, until the other day while I was in the middle of a 24" wide slab of pecan. I took it home and tore the top end down for the first time. He was right, it looked like very good work. The transfers had been worked from the bottom up, exhaust had been relieved and the intake looked like it had received a little work as well. Also the piston looked to be shaved a couple of thous. And last but not least, It had two base gaskets installed.

Is this common or an enhancment to the mod?

I am going to measure these mods and would like to compare them to stock for future reference. That is why I was wondering if anybody has this info at hand?

By the way, the only thing that was wrong with the saw was that the cylinder bolts had vibrated loose. I put on a little loctite, toqued them back down, and voila she's back to life again. Thanks for your patience but I though it would help to explain myself and give a little history of the saw.
Thanks
 
do you have any pictures of the outside or inside of the cylinder? the broken fins make me wonder if somebody dropped a tree on the saw once. if that was part of the mods i would be wondering about the builder..
 
It the modified saw that don't have any fins you have to worry about. Seriously.

Fred
 
Mr. said:
It the modified saw that don't have any fins you have to worry about. Seriously.

Fred

Maybe they installed a water pump while they were 'workin' her over' :hmm3grin2orange:

cooling fins were designed for a reason - proper heat transfer. A broken fin would worry me much, but SEVERAL missing fins is a HUGE problem and should throw up a red flag.
 
Thats why I would like to know how much from stock it bas been modified because I would like to try and replicate it into a new cylinder. It runs great and I have used it to mill some serious oak slabs (8' x 40+"wide) that took 15 min per cut with about 5 minute rests, with no obvious overheating problems. But I do realize that it could pose an overheating problem. That's precisely why I opened up the muffler and added a second exhaust port as soon as I got the saw. The cylinder and piston seem to be in great shape and overall it seems very solid still. Compression is 160 and it fires up every second pull from a cold start. Are all cylinders for the various makes of 066's identical, older aluminum flywheel and newer with poly flywheel?
 
NWCS said:
do you have any pictures of the outside or inside of the cylinder? the broken fins make me wonder if somebody dropped a tree on the saw once. if that was part of the mods i would be wondering about the builder..


I will take some pics of the outside and post them, and yes there was a tree dropped on this saw at some time but it had already been fixed up before the seller had it in his possesion.
 
The likely reason your cylinder bolts loosened was because of the two gaskets are packing down (I assume they are paper?)... be careful with loctite on cylinder bolts - the paper gaskets will still pack, but now you can't torque the cylinder down, and you can get air leaks.. The bolts are supposed to be in "dry".

Rather than paper gaskets, you should use the metal gaskets - they do not pack and have been standard issue on the 066 for many years.
 
I will go to the local dealer tomorrow and see if he has them in stock. Not very many 066's around here but I might get lucky. I'm sure he can order them though. What should I do about the thickness. There are two gaskets on it now, so should I put as many metal ones on as needed to match the thickness, or is that even an issue? You say be careful about the loctite, what kinds of problem might I have created for myself, if any? Thanks for your responses.
 
The loctite doesn't allow you to get a good torque value to re-tighten - the break-away torque is very high... If you use the RED like 272, it needs heat to break it or you can strip the magnesium threads. If it's Blue like 242, it will break ok, but a precision (pin point application) heat gun is a good idea. If you are lucky, there will be oil in the old threads and it won't have locked anyhow!

The metal gaskets are 0.5mm thick. It's hard to know what you will need to do as no doubt the modifier has messed with the squish clearance. I can't image you'll need two of them unless he took too much off the cylinder base.
 
I Heard Something About Baileys Getting Big Bore Cylinder Kits In The Later Part Of This Year For The 066's. Maybe It Would Be Something To Consider For Your Saw. Good Luck.
 
Removed cooling fins??? This is a mod I havn't done on a chain saw and I dont know why you would. Two base gaskets means that they probably milled the head and probably took it to far. As far as how much it has been modded, you would need to measure all of your port opening and closing with a degree wheel, and how much squish it has in the combustion chamber.
 
romeo said:
Removed cooling fins??? This is a mod I havn't done on a chain saw and I dont know why you would. Two base gaskets means that they probably milled the head and probably took it to far. As far as how much it has been modded, you would need to measure all of your port opening and closing with a degree wheel, and how much squish it has in the combustion chamber.


I'm sure that the fins were broken off from a tree falling on the saw or something. They were not removed as a modification to the saw. I was told that it was modified while brand new, before the fins were broken. As I can't see why anyone would modify a cylinder with broken fins.
 
lumberjackchef said:
As I can't see why anyone would modify a cylinder with broken fins.

Hey my 066 has three broken fins, but it is not a worksaw.

Romeo. Think about why there is fins and why that could be bad in a race environment. I won't even touch the bikesaw thing.

Fred
 

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