McCulloch Chain Saws

[db456]

Picked up a 7-10. What a little beast. This has more compression than any of my saws. First Mac that I have bought that did not need a carburetor rebuild. Fixed the starter, gapped the points and cleaned the contacts on the coil and it took right off. Great little saw.

 

[a. palmer jr.]

Picked up a 7-10. What a little beast. This has more compression than any of my saws. First Mac that I have bought that did not need a carburetor rebuild. Fixed the starter, gapped the points and cleaned the contacts on the coil and it took right off. Great little saw.

It looks to have a compression release, is that so?

 

[stinkbait]

It looks to have a compression release, is that so?

It looks like it has the old style compression release built into the on/off switch.

 

[a. palmer jr.]

It looks like it has the old style compression release built into the on/off switch.

That's what I was looking at...I had a 3-10 with that setup on it, called a DSP, I think.

 

[Eccentric]

McCulloch 7-10's all had comp releases. I've seen both the combination thumb button comp-release/throttle-lock setups that you guys are talking about, as well as the "regular" automatic resetting valve threaded into the cylinder on 7-10's (as seen on 'modern' saws). My 7-10A (and my PM700, and my SP-81) all have the automatic closing valve threaded into the head. Guys have posted pics of their 7-10's with the throttle-lock/comp-release setups in this thread before. Probably about 50 pages back.......:cool2:

 

[HeRoze]

===

Got this fixed - - there was a nick in the condenser wire, it was so close to the FW that it would short when the casting burrs passed over. I moved the wire and put some liquid electrical tape on it.

The compression gauge was still fine, and the saw is at 90 PSI.

Not running yet (fuel leak somewhere) but closer....

 

[54stude]

Got this fixed - - there was a nick in the condenser wire, it was so close to the FW that it would short when the casting burrs passed over. I moved the wire and put some liquid electrical tape on it.

The compression gauge was still fine, and the saw is at 90 PSI.

Not running yet (fuel leak somewhere) but closer....

Posts like this one are the reason forums are great. Now, we can add this to our memory banks to help us troubleshoot in the future.

 

[leeha]

Got this fixed - - there was a nick in the condenser wire, it was so close to the FW that it would short when the casting burrs passed over. I moved the wire and put some liquid electrical tape on it.

The compression gauge was still fine, and the saw is at 90 PSI.

Not running yet (fuel leak somewhere) but closer....

90 psi is very low. It way or may not run with
that type of compression. Somethings wrong somewhere.




Lee

 

[HeRoze]

Posts like this one are the reason forums are great. Now, we can add this to our memory banks to help us troubleshoot in the future.

it was a helluva exploration to find the root cause...

 

[HeRoze]

90 psi is very low. It way or may not run with
that type of compression. Somethings wrong somewhere.
Lee

agreed. I didn't pull the P&C on this one, so that leaves room for error. p&c looked fine though the ports. rings were floating correctly. head and crank gaskets weren't alarming. I also found the face of the spark plug hole is a bit buggered up. next attempt is to torque the plug a bit more with some teflon tape on the threads to see if it may be leaking a bit around the plug.

 

[Eccentric]

agreed. I didn't pull the P&C on this one, so that leaves room for error. p&c looked fine though the ports. rings were floating correctly. head and crank gaskets weren't alarming. I also found the face of the spark plug hole is a bit buggered up. next attempt is to torque the plug a bit more with some teflon tape on the threads to see if it may be leaking a bit around the plug.

The rings could be worn or carbon fouled. My Super 250 P/C look great through the exhaust port..............except both ring gaps are right at the exhaust port and the gap is around .125" (and they're still 'springy'). That's extrememly excessive (and explains the LOW compression on that saw). If the rings are carboned into the ring grooves of the piston, they won't seal against the cylinder well. Sometimes just pulling the thing apart and cleaning things up (carefully) will bring it back to life.

 

[homelitejim]

Picked up a CP70 today, I will have to assemble it but it is all there.

 

[Eccentric]

Picked up a CP70 today, I will have to assemble it but it is all there.

A Poulan 5200 and a CP70L Jim? Once again...............you suck!

That's the first CP70L (LH start) that I've seen. The non-L CP70's (like Duke T's) are RH start. Here are the IPL's for both types. You just keep on finding saws on my 'list'. I need to camp out at 'your' local scrap yard/honey hole....

http://www.smallenginediscount.com/CP_70_May_70.pdf

http://www.smallenginediscount.com/CP_70L_Oct_70.pdf

 

[homelitejim]

A Poulan 5200 and a CP70L Jim? Once again...............you suck!

That's the first CP70L (LH start) that I've seen. The non-L CP70's (like Duke T's) are RH start. Here are the IPL's for both types. You just keep on finding saws on my 'list'. I need to camp out at 'your' local scrap yard/honey hole....

http://www.smallenginediscount.com/CP_70_May_70.pdf

http://www.smallenginediscount.com/CP_70L_Oct_70.pdf

found them on craigslist for $50 plus he threw in a 10-10

 

[Eccentric]

found them on craigslist for $50 plus he threw in a 10-10

Yep. You suck...

 

[dce1843]

why cant i come accross stuff like that?

 

[Rounder]

Few of you guys might remember that I picked up an 895 quite a while back. Siezed tight. Looking through the ports, no scoring, just rust. Tried everything I could think of, never did let go.

Anyhow, came back across the block today and figured what the hell. Gave it a few little taps with the dead-blow and sure is #### it freed up. Piston looks good, cylinder looks good.

Guess I'll be getting after it - Sam

View attachment 229407

 

[db456]

Don't I know. Sometimes you have to walk away and come back later. Looks like a good project.

 

[Rounder]

Goddangit! Seeing that you "liked" my post reminded me that I still have a box of 250 parts for you Brian!! Too much #### going on latley to keep it all straight. They'll be in the mail Monday, on me. Sorry for my scatter-brainedness.

 

[JoeCT]

Mac6 strarter question... again

I asked how to get the starter spring back in place on a Power Mac6 over in in homeowner forum....

The reply was to "make a dealer show me".

Can anyone offer "cheaper" advice?