McCulloch Chain Saws

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A little goofy, but next time you are checking seals under vacuum I've found they whistle (sometimes) when you spray oil lie WD 40 on the rubber part of the seals if they are leaking. It can help to pinpoint the problem.

I would leave the gasket out and just use a piece of inner tube or two if the thickness requires it. That will eliminate the gasket as an issue when testing.

I will try that too and I will use rubber for the exhaust and see if that works better.
Thanks


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Well looks like I finally got the 440 running good. Won't be able to put it in wood till tomorrow evening though. Had to actually remove the points from the saw and use a combination of emery cloth and my point file to clean up the oxidation. Then I had to use pliers and tweak the spring a little to get them to make reliable contact. I brought home my fluke meter from work so I could just check continuity without a bunch of trial and error. I also bought a set of point feeler gauges instead of the old match book lol.

Anyway, once I cleared the excess fuel out of it it ran and I was able to tune the idle mixture to give a nice even idle and crisp throttle response. Still has a nice fourstroke at wot. Will fine tune the high in wood tomorrow. Pretty stoked right now.
In other news.... it looks like the deal on the 550 is probably gonna fall through. A fellow AS member that lives local checked on it for me and the guy has a buyer coming on Saturday. If that falls through we are next in line. Kinda bummed but oh well [emoji53]
 
PM375 is in the 300 family. I worked on my first 300 Series saws a few weeks ago and they are not so bad. Certainly they do things differently with the odd ball rubber intake boot/seal. Many of the 300 Series saws carry the "Professional" label...not sure why.

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As terrible as that rear handle looks on that 375, it is more practical if you are trying to buck up some firewood that the top handle version.

Mark
 
So I just bought a really large bar off eBay on a whim for the 440. Really just for looks as opposed to functionality lol. I'm switching to 3/8" chain. Have a rim on the way as well. That being said, how do I tell how many drive links I'm gonna need for this monster? I don't believe it is marked on the bar like modern stuff. By the way, it is advertised as a 34" bar and is a bit over 36" overall. It is a hard nose mcculloch bar.
 
Mark,
Just out of curiosity, how do you think the 440 will do pulling a bar that big? Planning to run skip tooth full chisel 3/8".
Again, I'm not a logger and don't plan to really use the saw as much as I just think it's neat lol.
 
The 440 is really just another 87 cc model like the 1-52/53, 300, 380. The top tank was intended to make it a more "professional" model to avoid the problems with the front tank saws boiling the fuel.

I have a 1-72 which is an earlier version of the top tank 87 cc saw without an automatic oiler. If it had an auto oiler I would use it more as I think it is more fun to run than my 066 Stihl was when I had it. I put the 066 aside to use the 1-72 on this maple in my front yard (neighbors tree but I dropped it across my parking).

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I have only used my 440 one time and I made one or two cuts before hitting some iron buried in the tree. It was easier to manipulate than the 840 with the 48" bar I had been using on the big stem of that tree.

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With a good selection of 82 cc 10 Series saws with good anti-vibe it is hard to drag out the big iron for most projects.

Mark
 
So went to run the 440 tonight and having a weird problem with it. It is not taking throttle....... like no bog or anything, just no change. Like it is sitting there on the bench idling along, I stab the throttle wide open, and nothing!!!! No rev, no bog, it just continues to sit there and idle, how can that be? What am I missing. It will pick up rpm if I kind of feather it off idle and it has a nice burble at wot with no load.
I have just never seen any motor behave like this and don't even know where to start with it.
Also, I put new crank seals in it but did not do a pressure test. But I also did not take apart any gaskets either.
 
Lol [emoji23] yes...... and I can still feather the rpms up. It's just when I stab the throttle. I've never seen this, seen plenty of engines have an off idle bog but never not do anything when you hit the throttle.

Btw, I've been an auto technician for the last 18 years so I know my way around motors ok. [emoji12]
 
OK, Sorry when people ask questions you don't know what their skill level is and it sounds like you have quite a bit of experience. I assume you cleaned the carb, did you use a kit and replace the gaskets and diaphragms? I have not been keeping up with your posts. Have you tried to rich or lean the low adjust? If you have cleaned the carb could you have gotten some dirt or junk in it after you cleaned it? I have done this before. I have gotten in the habit of cleaning new fuel hose before I install it because I have cleaned a carb and while tuning it it start acting like it was clogged up again and reclean the carb and then things start running fine. The only thing I could find would have been the new fuel line must have had some junk in it. So I just clean them out before I install them. Either that or something I missed while cleaning. Could you have the same thing going on here? You say that you feather the throttle and then can get it to open up? If that is the case three things come to mind. Dirt in the low idle circuit in the carb, a broken reed or leak in the crankcase. By the way I am unfamiliar with the 440, some saws had a governor on the throttle circuit does this saw have this? If so is it operating properly? Just a thought.

Brian
 
No governer, yes, I have been in the carb car quite a few times at this point. No kit yet it is on the way but being a flatback it is quite a wait for a kit. I was also thinking air leak but I put new crank seals in and I didn't break any of the other gaskets open in saw.
 

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