McCulloch Chain Saws

[edju1958]

I got the SP40 out yesterday & fueled it up to see if it'd at least run.Either the fuel filter is plugged,or it needs to have the carb rebuilt or both.It'd run on a prime,but as soon as the fuel was used it'd die.And of course the oil line must not have plugged into the oil tank when I put the tanks on,oil leaking.I let it set outside in the frigid temps last night to reflect on it's actions.I know it's an inanimate object,but it makes me feel better.

 

[heimannm]

Ed - you can see the connector and guide it into the spot on the tank as you slide the tank into the saw.



Mark

 

[bob kern]

Yeah,& I'm looking for cheese,LOL. Jethro,I've been called much worse.

What you need is a cub cadet to be well rounded.

 

[Rotax Steve]

I ended up stealing the switch off my 610 build from last summer (had problems with it & wouldn't run right).I got it al;l together & noticed the needle grommet is missing,but it fired right up & ran beautifully on about the 4th or 5th pull.That 610 has great compression.


So when I had the 610 build from last summer apart to sdteal the switch out of it,I noticed the FW was loose.Me being a dumb *** & always in a hurry forgot to tighten down the FW nut.I took care of that & put the recoil back on & hoped that it'd start & run fine as I'd replaced the FW side crank seal (the other PTO seal was replaced before I started putting it together).It does run,but it idles hi & lo & I had to turn the needles out more than usual.It's got an air leak somewhere that I can't figure out.I guess I'll have to tear it down & start from scratch & try to get it right.

I had a 7-10 that was like that. It would start fine and idle but it was like it had a mind of own and would rev up and down. I figured out it was a leak at the intake manifold.

 

[edju1958]

I had a 7-10 that was like that. It would start fine and idle but it was like it had a mind of own and would rev up and down. I figured out it was a leak at the intake manifold.

Thanks Steve! That's what I was leaning towards.I got the gaskets from Mark,just haven't gotten around to tearing into it yet.Maybe later this week or next week.

 

[heimannm]

I have been struggling with this 6-10 for a few weeks (off and on), it will start and run, runs very strong in the cut, but frequently acts very lean when coming out of the cut, occasionally adjusting the carburetor would help but it just would not tune. Then suddenly it would either flood out or run so lean it would stop.

I've had it back down to the short block 3 or 4 times, pressure and vacuum test are great with the pulse pump (automatic oiler) blocked off, very slow leaks with the pulse pump in place...I finally replaced the pulse pump with one fully rebuilt and it slowed the leak fairly well. Did I mention that the crankcase and seals pass pressure and vacuum with flying colors???

I've had 4 different carburetors on it with very little difference in performance.

I finally started pressure testing as the rest of the intake was going together...the insulator (next to the cylinder) was fine, but when I pressure tested with the tank and spacer installed there was a noticeable leak.



I tried scraping the surface to get it flat but just couldn't get it to where I wanted it, so I secured it on the mill/drill and machined the boss flat.



I really hope this will take care of it, I'm sure the owner of the saw is beginning to wonder...

If anyone has additional suggestions/recommendations, I welcome all input.

Way back in the beginning of the process, new piston installed.



FYI, it has the three screw aluminum body pulse pump so make sure you remove the block after pressure vacuum testing or you get to do it all over again.

Mark

 

[edju1958]

I have been struggling with this 6-10 for a few weeks (off and on), it will start and run, runs very strong in the cut, but frequently acts very lean when coming out of the cut, occasionally adjusting the carburetor would help but it just would not tune. Then suddenly it would either flood out or run so lean it would stop.

I've had it back down to the short block 3 or 4 times, pressure and vacuum test are great with the pulse pump (automatic oiler) blocked off, very slow leaks with the pulse pump in place...I finally replaced the pulse pump with one fully rebuilt and it slowed the leak fairly well. Did I mention that the crankcase and seals pass pressure and vacuum with flying colors???

I've had 4 different carburetors on it with very little difference in performance.

I finally started pressure testing as the rest of the intake was going together...the insulator (next to the cylinder) was fine, but when I pressure tested with the tank and spacer installed there was a noticeable leak.

View attachment 1151295

I tried scraping the surface to get it flat but just couldn't get it to where I wanted it, so I secured it on the mill/drill and machined the boss flat.

View attachment 1151296

I really hope this will take care of it, I'm sure the owner of the saw is beginning to wonder...

If anyone has additional suggestions/recommendations, I welcome all input.

Way back in the beginning of the process, new piston installed.

View attachment 1151297

FYI, it has the three screw aluminum body pulse pump so make sure you remove the block after pressure vacuum testing or you get to do it all over again.

Mark

Mark,you've chased this down more than anyone else would.We're waiting with bated breath to see how this plays out.

 

[heimannm]

Success! I used a little Dirko on both sides of the gasket against the tank bottom and Pliobond on the gasket to fix it to the spacer, make reassembly a little easier.

This one has the spring loaded adjuster with the "swivel joints" so it take a little effort to get the carburetor in place.



The 6-10 now behaves as it should. The clutch is old and the springs are a bit weak so it takes a few seconds for the chain to come to a stop, but it idles down nicely and accelerates quickly. Feels pretty good in the cut.

If I can get the video up upload in YouTube I will post a link.



Mark

 

[heimannm]

 

[edju1958]

I got some of the saws that I bought last week (PM610s).I kinda felt sorry for the FedEx driver - there were 4 powerheads in one box,Lol.The other box had a seized PM605 & a ton of parts including 4 20 in.bars & chains.The chains are almost brand new..The saws have great compression! Tomorrow I'll be going through them more.I've still got one or two more boxes coming,Lol.

 

[edju1958]

I started tearing into the Monkey Wards saw yesterday & found that one of the ears where the small screw holds the recoil on was broken off.I also saw that the fuel line wasn't original & was disintegrated.I was going to put a Tygon line on,but fouind I was out of that size line.I had a good recoil from another Wards saw that I bought last summer & used that.I also noticed that ther PM605 had a good fuel line in it & I just swapped fuel tanks.I cleaned the saw really well as it was loaded up pretty good by the ignition module with lots of crud.I put it back together just as I was losing daylight & gave it a prime to see if it'd fire & it did.It needs a new fuel filter & possibly a carb rebuild.Keep in mind that all these saws were running when put away.It must've been put away about 20 or 30 yrs.ago because there was almost an 1/8 in.of dust covering these saws.

I then moved on to a 610 that was owned by the devil himself.The rope was hanging out about 6-8 in.,so I pulled the rercoil off for retensioning & found the filthiest saw that I'd ever seen.I had to pull the saw completely apart to clean it.It must've taken me half the day to do so.What really amazed me was how much compression the saw had & the air box was actually clean.I was in the process of putting it back together & noticed that the 2 screws that hold the switch plate onto the cylinder were missing,so I had to stop there.I may have a couple of them in a box of parts I got from Mark,just gotta look.

The PM605 engine is no lopnger seized.I was able to free it up by turning the FW by hand just a tad.I then sprayed some Deep Creep into the cylinder & it's working freely.The saw was pretty much dismantled & the recoil was destroyed by taking it apart & losing half of the parts.They even dismantled the air box.

 

[heimannm]

A good PM610 type saw will have 180+ PSI compression.

They still run alright down around 135...

Mark

 

[edju1958]

I forgot to mention that I got the 610 build from last summer running.I put the gaskets in that I got from Mark & it runs much betterr,BUT....I still had to turn the needles out further than normal (1-1 /1/2 turns) & the idle screw is turned out all the way.I'm beginning to wonder if the problem isn't in the carb?It's a new Zama that I got last yr.on feebay.

 

[Syncop8r]

I started tearing into the Monkey Wards saw yesterday & found that one of the ears where the small screw holds the recoil on was broken off.

Was it the one near the switch?

 

[heimannm]

 

[edju1958]

Was it the one near the switch?

I think you misunderstood me.That whole assembly that covers the left side of the saw is called the fan housing which includes the recoil (the square box that has the rope on it & is held in place by 4 screws) & the fuel tank.

 

[heimannm]

 

[edju1958]

I got home today from the monthly shopping & put a new fuel filter in the Monkey Wards & put fuel in it.A few pulls later it was running like it did yrs.ago.It just needed a slight carb adjustment & stepped up the idle a bit.I didn't have a chance to put a bar & chain on it yet.It needs bar stud nuts.

 

[edju1958]

I got the used to be filthy 610 almost completely back together.I found the screws I needed on the PM605 switch plate.All that's needed now is to put the carb back on & see if it'll run without a rebuild.
I ended up tearing into another 610 after it fired on a prime.How it fired I have no idea.The previous 610 & this one are fairly close as to how dirty they are/were.This time I took a pic.I think this one was owned by the devil's brother.

 

[Syncop8r]

I think you misunderstood me.That whole assembly that covers the left side of the saw is called the fan housing which includes the recoil (the square box that has the rope on it & is held in place by 4 screws) & the fuel tank.

I have assumed you're talking about a 610; if not, that's where the misunderstanding is.
I have one where the tab broke off near the switch, which is why I asked if yours was in the same place.

As to your describing the fan housing to me, I find that rather condescending. (Condescending means talking down to people)