It will vary depending on elevation and atmospheric conditions at the time the reading was taken. Many things affect a compression test reading which is why there is no distinct line between good and bad.
Back in from the cold and rain. I got out my 372 and did the compression test on it. Guess what I got. No, not 120#, about 123#. So that verifies this gauge is junk. I adjusted on the carb a bit and made several cuts. I'm working on getting a video uploaded. I always have trouble with YouTube.
That's much better ..................... BUT I would keep going until you hear the 4 stroking in the cut, then back off on the high a smidgeon. Its tough to tell in the video, you have seen a lean tune loose power (1 min 44 sec), too much will 4 stroke in the cut. Keep adding a little more fuel, you are just about there IMHO Its mucho better to be a little fat than a little lean (carb adjustments). I like hearing the 4 stroke as I am finishing a cut and as I transition off dogs. She should not clean up as soon as you hit the wood, but rather clean up as you get about 1/4 of the bar being used ............. this is where I notice all of my saws making real good power and running nice and cool @ 21 seconds in the video, she 4 strokes hard WOT (right there is where I would have tried a cut)...........then you adjust again and around 30 seconds .............. I can hear the slight 4 stroke near 30 seconds, but I believe that tune is still too lean. Nothing beats being there, so its all up to you ..............your last 2 cuts look like the saw is making some power now, but I wonder if there is more power in that saw if it drinks just a little more fuel ??
I agree. Looked much better but still needs that muffler gutted! My ported 461 cuts way better than that!! A muffler mod would help it alot imo
Absolutely ...................... however, I still think the saw has more in the carb without gutting the muffler. My 066 ??? I gutted it 5 minutes after its first cut, didn't even wait for it to cool down A ported 461 will allways give a stock 660 a beating
Thank you! I think the first couple of cuts are with the screw maxed out to the left. Thats the only way to get more fuel right? Will the L screw do me anything running WOT?
No, the L screw is for fuel at idle speed and for transition from idle to WOT, normally when it bogs on acceleration it needs more fuel on the low jet circuit. The low jet has nothing to do with high speed jetting.
We are allways here to help !! You need to pull the limiters so you can get that carb tuned perfectly
Just about every carb I have tuned must have the high re-adjusted after the low is adjusted (for whatever reason). The low speed feeds fuel at idle and all other throttle settings, remember its being pulled up by crankcase vacuum, not just when the throttle butterfly is closed
Sure is ................... Get a sheetrock screw, screw it into one of those little red plastic POS caps and screw it until its fairly snug, then with pliers - yank hard Write up complete
Still sounds a little lean. Ever put a tach on it? When my 660 was stock it 4-stroked well around 13K with 93 octane at 32:1 mix. After porting, with the same fuel mix, it would 4-stroke 14K+. Although it's set around 13,600 rpms now. A dual port muffler helps a lot and also removing the entire baffle.
