NkyKelly
ArboristSite Lurker
I will start by saying I think that I have read every thread here and other sites regarding Chainsaw Rebuilds. Unfortunately, I seem to have some kind of mental block on understanding this or I have a unique problem. Either way I'm hoping you can help...
I have owned a Stihl 066 for 16 years. I purchased it as a Powerhead (without Bar/Chain) for a Chainsaw mill. I really haven't used it much, but I did get a 20" bar for it to use for Yard and Farm projects. I had actually written a long version of this, but decided not to bore anyone and turned it into as shortest of a bulleted list as possible.
Still a long story..
So, where do I go from here? I have rebuilt a two-cylinder Jet Ski motor without an issue, but this thing has me stumped. Its just way too sensitive. Based on what I read, an issue that causes this kind of destruction with just a tank of Gas should be very big and easy to find.
Am I missing something or just being stupid? Is there a way to know whether it is in fact running too hot before its too late and I simply burn up another top-end
I have read threads telling other people to send their saw to one of the guys here and have it "gone-threw". Who does that and what does it costs. I think I have the parts already, would someone be willing to use the parts I have already. Heck, I even have another Cylinder and Piston set that I ordered from Hong Kong originally. (Took 30 days to get here).
I simply just don't want to keep doing this to myself. I want to get to milling and focus on my woodworking.
Thanks,
Kelly
I have owned a Stihl 066 for 16 years. I purchased it as a Powerhead (without Bar/Chain) for a Chainsaw mill. I really haven't used it much, but I did get a 20" bar for it to use for Yard and Farm projects. I had actually written a long version of this, but decided not to bore anyone and turned it into as shortest of a bulleted list as possible.
Still a long story..
- In late April I used the saw to prepare some logs for milling. Used saw on and off for 4 hours running a tank and half through it. Saw some smoke at the end, but all seemed good and did not really notice power drop until very end. Chain was dull so I quit for the day.
- Next day, saw wouldn't start. Compression was low, but not gone. Took to Stihl Dealer and disovered burnt up Piston and Cylinder. You could see the scorching through exhaust port.
- Dealer said it wasn't worth repairing, but while searching to see what the used parts were worth on eBay, I discovered Asian made replacement parts for it. So I ordered a Big Bore Cylinder, Piston, Rings and Gasket set from a guy in the states.
- Did the rebuild and everything looked good. Saw started right up, but it didn't idle well. I didn't adjust anything, but I did follow some basic break-in procedures that I read here and other places. Ran half-tank of rich 35/1 mix. Ran for 15-20 minutes never going above 75%-80% throttle. All seemed good.
- The next day it started right up and I proceeded to run it much harder. Ran off and on for 2 or 3 hours using about 3/4 of a tank (35/1 mix). Saw started everytime, but didn't idle well. Chain was not bad, but not great. At one point, I noticed that the it was really losing power. I had to go to family event so I left the saw to cool.
- When I got back to the saw the next day, the saw was hard to start and did not run well enough to use. I removed the muffler and discovered another scorhced/burnt piston.
- I realized that I was stupid. I didn't even investigate what might have caused the original failure. Once I read things on the web, I realized leaving everything the same was very very stupid. Afterall, something caused the original problem and I knew it wasn't Straight Fuel since I was the one that was using it.
- The vendor was great. When I gave him my honest story and asked about a discount on replacement he replaced them as warranty. He even gave some advice as to usual causes and threw-in a new intake boot.
- I completed the 2nd rebuild over the weekend. This time I finished by doing some basic pressure testing (Poor Man's version) and all seemed good. I really focused on making sure all gaskets, boots and hoses were good. Based on what I have seen, the pressure test was positive. I put the Carb back on and the saw back together.
- I adjusted the Carb using techniques here and around the web. Once I had it good, I set the High Adjustment 1/4 turn Rich to be safe.
- The saw was running great last night and I proceeded to make a finish a cut on a stump.I didn't run it much, but it sure seems like the Cyclinder and Muffler is getting extremely hot.
- I don't think I burned anything up, but now I'm scared to run it. I certainly don't want to put it on the Chainsaw Mill because that runs the saw harder than anything. Of course, the Chainsaw Mill is my whole reason for wanting this running so I am bummed out.
So, where do I go from here? I have rebuilt a two-cylinder Jet Ski motor without an issue, but this thing has me stumped. Its just way too sensitive. Based on what I read, an issue that causes this kind of destruction with just a tank of Gas should be very big and easy to find.
Am I missing something or just being stupid? Is there a way to know whether it is in fact running too hot before its too late and I simply burn up another top-end
I have read threads telling other people to send their saw to one of the guys here and have it "gone-threw". Who does that and what does it costs. I think I have the parts already, would someone be willing to use the parts I have already. Heck, I even have another Cylinder and Piston set that I ordered from Hong Kong originally. (Took 30 days to get here).
I simply just don't want to keep doing this to myself. I want to get to milling and focus on my woodworking.
Thanks,
Kelly