Can somebody explain this?

[a. palmer jr.]

I was cutting up a big maple tree with my Mac 10-10 and stopped for a little while for some reason (can't remember). The saw ran well but wasn't a real powerhouse with the 20" bar but was doing all right. When I went to start it back up it wouldn't fire at all. I pulled on it numerous times but it wouldn't go and it seemed like it didn't have any compression or it was very low. I went back the next day kinda curious and pulled the rope again and it seemed to have more compression than the day before so I turned it on and put on the choke and she started right up! I checked and couldn't see a compression release so I don't think that was it. It's got me baffled that it could have compression one day and not the next. Am I missing something?

 

[PLMCRZY]

Loose jug bolt? When it heats up it gets even looser?

 

[a. palmer jr.]

I'll try to check it out when I can. I won't be home tomorrow but maybe Wednesday I'll look it over. I had thought it may have a hidden comp. release but if it is it's really hidden. I know where they usually are on these saws.

 

[caotropheus]

A. Palmer, are you sure that there was a lack of compression? Probably some impurity in the fuel line and not enough fuel in the cylinder?

 

[a. palmer jr.]

A. Palmer, are you sure that there was a lack of compression? Probably some impurity in the fuel line and not enough fuel in the cylinder?

Not really sure of anything at this point. This is an old saw and didn't really have a lot of compression but enough to run. I thought for awhile that I forgot to turn the ignition to "on" but I'm usually pretty careful about that and think I checked it. I also thought the coil might be going bad and maybe opened up when it got hot. I'll try it again in a couple of days and see if it does it again.

 

[lawnmowertech37]

palmer if you find out you need rings i have a set of rings for the 10-10

 

[blsnelling]

Did you boil the fuel? That happens sometimes when you work the old all metal saws hard.

 

[a. palmer jr.]

Did you boil the fuel? That happens sometimes when you work the old all metal saws hard.

Yes, I think I did boil the fuel. I heard a little hissing noise when I quit using it. I guess I should have connected the dots better but sometimes I don't. Thanks

 

[tmessenger]

If you were pulling the saw hard and it got hot the cylinder expands at a greater rate then the piston/rings and loses compression ? If compression is already on the low side then maybe time for a rebuild.

 

[a. palmer jr.]

If you were pulling the saw hard and it got hot the cylinder expands at a greater rate then the piston/rings and loses compression ? If compression is already on the low side then maybe time for a rebuild.

Not sure what I'll do with the saw..I have two others that are in better shape, a Pro Mac 700, and a Pro Mac 55 which I've had for a short time. A rebuild is possible but probably not likely.

 

[a. palmer jr.]

I used the 10-10 again today. It seemed to run just fine if you don't count the lousy thing pulling to one side in the cut. I'm not sure now if it's the tree, which has 1000 knots in it or my sharpening job on the chain. I tried a couple of other saws and they all pulled except my Super XL which ran fairly straight.

 

[abikerboy]

palmer if you find out you need rings i have a set of rings for the 10-10

Calvin, do ya happen to have an auto oil pump for one of these? PM10-10S...

 

[BigE]

I used the 10-10 again today. It seemed to run just fine if you don't count the lousy thing pulling to one side in the cut. I'm not sure now if it's the tree, which has 1000 knots in it or my sharpening job on the chain. I tried a couple of other saws and they all pulled except my Super XL which ran fairly straight.

I'd guess sharpening. Make sure all the teeth are the same length, and make sure the rakers are filed correctly.

Whenever my saw starts pulling to the side, it is usually an issue with the rakers.

Regards,
-Steve

 

[lone wolf]

Sounds like a heat seizure.

 

[a. palmer jr.]

Sounds like a heat seizure.

I think I had the heat seizure while cutting the tree up...not used to that much work. I've since put the 10-10 up and am using a couple of saws that are more up to the task, my Mac 55 with 24" bar and my Pro Mac 700. There's a world of difference between the speed of the 700 and the rest of my saws! It seems I run into this crooked cutting every now and then when using saws that are 20" or so. I guess it's because there's more cutters thus more chance for error in sharpening. I figured out what was wrong with my Dayton saw..I counted the cutters and it had 17 on one side and 14 on the other. I ordered a new chain for it.