...and more on the XL 901...
I got the welch plug properly seated and tried that. It runs better but still not very good. I tried it first with the needle valve set as pictured above. It would only start on prime, but it would run for pretty good burst and then just die after about 8 seconds. It seemed like it was just running out of gas so I went back into the carb and raised the needle as to try to richer it up. It would not adjust out with the high speed jet so I figured I needed to do something with the needle setting.
After I raised the needle setting, it improved but still not good. At one turn open on the high speed screw, it would start after priming and run finally long enough for me to adjust it. Before adjusting it would run super rich so I slowly closed the screw. It would run really good, fast, and strong after I tightened the screw to like only 1/4 turn open. It would run as long as I had it wide open. If I let off the throttle to see if it would idle, it would just die. And I cannot get it to restart even with a prime at that high speed setting at 1/4 turn.
There are times it will start with the throttle lock on which is probably like at 1/4 throttle, but as soon as you try to open up the throttle it just dies. The low speed jet is set at 1 turn.
I am wondering if I have a messed up carb or got a bad diaphragm in the kit I put in. Any thoughts would be appreciated and my right arm would really appreciate you. Thanks!
finally...Finally...FINALLY!!! The 901 lives.
I took fossil's advice and found another carb for it on evilbay. I installed the new (used) carb. Wouldn't run right. Put a new kit in it and she runs, idles, and everything. I haven't had it in wood yet. For whatever reason, I just didn't solve the riddle of that original carb. Maybe that's why the old had been put on the shelf for retirement.
Here's a few things I learned from working so long on this old saw:
1) first off let me say I memorized the entire Johnny Western "Have Gun Will Travel" and Marty Robbins "Gunfighter Ballads" while working on this one. Kept me from going ballistic.
2) while starting this saw, the slightest bit of richness - not even actually flooded - will cause this saw to kick back. My elbow may hurt from now on.
3) a little bit of penetrating oil in the flywheel key way seems to helps the flywheel come off a lot easier
4) permeatex moto-seal is now my favorite fuel sealer
5) I'll probably be crucified for this but here it goes: an old saw with Phillips head screws holding the tank together with the inside of the tank completely petrified with screws so configured that you can't cut slots in the heads or do other tricks is perhaps best left alone to used for decoration or something.
So here's my next question: how big of a bar can this saw effectively pull? 77cc's with 138 psi compression cold. I need a saw with a larger bar to go with my gang of little saws. It came with a decent enough old 16" bar with the worn outest chain I've ever seen. I was thinking of a 26" bar. Your thoughts and recommendations please. Thanks!
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