HeRoze
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Does everyone already have a copy of this?: McCulloch Publications Guide. It seems to list all the models, S/N prefixes, IPL document #, Owners Manual #, Service Manual #, dates of production. Chainsaws are first.
McCulloch Chain Saws
- Thread starter Bruce Hopf
- Start date
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RandyMac
Stiff Member
I use a metal oil can with a bendable spout, you know, those domed ones that you press on the bottom. That bendy nozzle can get to almost any carb throat and there is great control of fuel amount.
HeRoze
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Pulling Piston?
before i really screw this thing up, i'm pulling the piston and it is putting up a fight. I've eased it out roughly 2/3 of the way and am having to use quite a bit of force. any tips?
before i really screw this thing up, i'm pulling the piston and it is putting up a fight. I've eased it out roughly 2/3 of the way and am having to use quite a bit of force. any tips?
You mean out of the cylinder? Wow, it shouldn't be that hard. Did you squirt some oil into the cylinder before you tried to pull the piston out?
Possibly the cylinder has a lot of wear and you are pulling it past where the rings have worn into the cylinder. It's smaller there than where the rings were going up and down, or it's possible a ring may have come out of its groove.
Thanks for the publication guide Vic, nice format for computer searches.
What saw are you working one that's giving you trouble pulling the piston out?
Mark
What saw are you working one that's giving you trouble pulling the piston out?
Mark
HeRoze
Addicted to ArboristSite
pulling the piston out of the bottom of that 640.
PROMAC: yea, I've been bathing this thing in MMO on and off since I started with it. It wasn't seized when I started, for sure.
A. PALMER: of those two options, I would bet on the rings, but am not sure. Before I pressed out the crank I was able to move the piston with the crank.
I'm sure I can yank the thing out, but really don't want to bugger up the cylinder if it is avoidable. I don't want to put more money into this machine than is required to fix it or to help it be more reliable. breaking things as I take it apart ticks me off, too.
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Eccentric
Mister Wizard
Thanks for the download Vic! Repped you for it.
As for your 640.......my money also rests on hung up rings. Since that saw has an iron liner, I'll bet there's a ring ridge worn into the jug. The rings just won't ride over it. Since it's at near the bottom of the jug............this is gonna be dificult. Ring ridges in automotive blocks sometimes are so bad that you need to use a ring ridge cutter to clean it up enough to get the piston out. Unfortunately, you can't get a cutter up from the bottom to that ridge.
Think you're gonna have to break the piston rings. Done right, you won't hurt the cylinder. It's going to have to rebored anyways if it has that bad of a ring ridge. May damage the piston. No big deal there either, as you're gonna have to replace it with an overbore piston. If you can get the piston back up to where the rings are exposed through the exhaust port and/or boost port window, then you can break the rings by placing a small punch or screwdriver against them, pushing them as far into the ring grooves as they'll go, and carefully whacking the punch/screwdriver with a hammer. May have to break the rings in several places and fish the pieces out. Piston will come out fine then...
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Thanks for the download Vic! Repped you for it.
As for your 640.......my money also rests on hung up rings. Since that saw has an iron liner, I'll bet there's a ring ridge worn into the jug. The rings just won't ride over it. Since it's at near the bottom of the jug............this is gonna be dificult. Ring ridges in automotive blocks sometimes are so bad that you need to use a ring ridge cutter to clean it up enough to get the piston out. Unfortunately, you can't get a cutter up from the bottom to that ridge.
Think you're gonna have to break the piston rings. Done right, you won't hurt the cylinder. It's going to have to rebored anyways if it has that bad of a ring ridge. May damage the piston. No big deal there either, as you're gonna have to replace it with an overbore piston. If you can get the piston back up to where the rings are exposed through the exhaust port and/or boost port window, then you can break the rings by placing a small punch or screwdriver against them, pushing them as far into the ring grooves as they'll go, and carefully whacking the punch/screwdriver with a hammer. May have to break the rings in several places and fish the pieces out. Piston will come out fine then...
Sounds like that saw has been used a lot!
lawnmowertech37
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1375619cm3
ArboristSite Operative
Mac 1-51 Help
First off i want to thank everyone that has helped me so far getting my grandpa 1-51 back running with out you guys it wouldnt of happened.
My question is that in order to get her started i have to spray a lil mix in the carb is this normal or what should i look for to fix it.
Also i got her to idle pretty good but when u rev it up in to the top end she just wont stay there it runs good for a few seconds and then acts like she is starving for fuel and tries to die. i can keep her running buy pushing in the choke button but at that point there is no power.
I have tried and tried to get it tuned in in the top end but this problem continues no matter what i do with the high needle.
Any idea's are welcome Thanks in advance
First off i want to thank everyone that has helped me so far getting my grandpa 1-51 back running with out you guys it wouldnt of happened.
My question is that in order to get her started i have to spray a lil mix in the carb is this normal or what should i look for to fix it.
Also i got her to idle pretty good but when u rev it up in to the top end she just wont stay there it runs good for a few seconds and then acts like she is starving for fuel and tries to die. i can keep her running buy pushing in the choke button but at that point there is no power.
I have tried and tried to get it tuned in in the top end but this problem continues no matter what i do with the high needle.
Any idea's are welcome Thanks in advance
Eccentric
Mister Wizard
Yep. Probably 'dusted' with a sorry or missing AF (or a missing adjustment hole cover or oiler/choke/primer rod grommets or...). Been my experience that 'dusted' engines often end up with a nasty case of the ring ridges...:msp_cursing:
HeRoze
Addicted to ArboristSite
actually it doesn't really look like it has. I think most, if not all, of its issues come from improper storage and general corrosion. none of the wear parts are worn at all. if you check back a few posts you can see the chain sprocket --- can't even see witness marks from the chain. the chain and bar are nearly unused, but the chain was rusty and the bar has lost some of its surface treatment. the bar is nearly dead flat in plane, not warped like most bows, particuluarly of this size.
i'm not convinced that I didn't screw up the rings when pushing the piston up into the cylindar prior to pulling the crank.
HeRoze
Addicted to ArboristSite
that may be true...
Not sure what carburetor it has on it but it sounds like it might need a good cleaning. If it were mine I'd just do the ordinary tune up to it, carb clean and kit, new fuel lines and filter, spark plug,... air filter(if you can find one, otherwise clean it up as much as you can.)
1375619cm3
ArboristSite Operative
Mac 1-51
the only thing i havent done was a new carb kit for it the one on it looks in good condition but could be no good. i have dis assembled the carb and soaked it in seafoam and can easily blow thru it. is there a better way to clean the carb? also the carb is a Tillotson.
the only thing i havent done was a new carb kit for it the one on it looks in good condition but could be no good. i have dis assembled the carb and soaked it in seafoam and can easily blow thru it. is there a better way to clean the carb? also the carb is a Tillotson.
137 - Sounds to me like the diaphragms are stiff. Replace the diaphragms and gaskets, make sure the metering lever is set correctly, and start out with the H and L screws both turned out about 1-1/4 turns. Diaphragms & gaskets should cost $5 to $8, full repair kit about double.
If you are unfamiliar with the carburetor or how to go about it, look for Gasoline71's Tillotson HL rebuild thread.
Mark
If you are unfamiliar with the carburetor or how to go about it, look for Gasoline71's Tillotson HL rebuild thread.
Mark
HeRoze
Addicted to ArboristSite
I'm betting a young ostrich. it cracked me up when i saw it, so i pilfered it as my avatar!
HeRoze
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Apparently DA (person who tried to work on this thing before) got that same advice! Well, he got the first half of that advice and not the 'done right' part. or maybe something got sucked in to the chamber. nothing fell out when i pulled it. here is what I found. There is a little circle from another perspective in the pic as well... Luckily the cylinder doesn't look too scored. we'll see.
cpr
Addicted to ArboristSite
Yowza, that piston is DONE. Hope the jug's okay, but luckily, McCulloch could see the future and made overbore pistons and rings. If you have to bore the jug, you will find the piston to make it live again.
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