I was gifted an SP40 by Ron Woods a couple weeks back (thank you Ron).He seems to think that I have more patience than he has (yeah right,don't you read my posts Ron?Lol).I haven't been able to do a heck of a lot due to knuckle replacement surgery,but today I tore into the old gal.This saw is fairly easy to work on,unlike the mini macs.Ron told me that the fuel tank had a leak.I just had a gut feeling that it was the fuel line & not the tank.Of course I haven't tested the tank yet to prove my theory.I did however find a kink in the "aftermarket" fuel line (Tygon I believe) right up close to the barb on the fuel tank.It could be a combination bad fuel line & leaky fuel tank.In any case,rather than replace the line with an OEM line,I'm wondering if it'd be alright to just replace the damaged Tygon line?I think the reason why the Tygon line kinked was because it's not stiff enough.I have a section of line that's stiffer than Tygon.
McCulloch Chain Saws
- Thread starter Bruce Hopf
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Tygon will work fine as long as the length and diameter are correct (3-1/2"). When you slip the engine back into the housing be sure the fitting is properly oriented and pops into the opening in the bottom of the housing and you will be fine.
Some early saws had a larger nipple on the carburetor and required a special fuel line with different diameter openings on each end (McCulloch was good at doing this) but the SP40 should use a 1/8" I.D. hose on each end.
FWIW, some of the very early Mini Mac models had a molded fuel line with a "ball" on the tank end that fit into the opening on the tank. They were notorious for shrinking and leaking.
Mark
Some early saws had a larger nipple on the carburetor and required a special fuel line with different diameter openings on each end (McCulloch was good at doing this) but the SP40 should use a 1/8" I.D. hose on each end.
FWIW, some of the very early Mini Mac models had a molded fuel line with a "ball" on the tank end that fit into the opening on the tank. They were notorious for shrinking and leaking.
Mark
I didn't have to take the engine out of it's case.I just took the chain brake off,the front cover,& the recoil assembly.
The fitting that goes into the fuel tank has a flattened side,which way should that fl;at side go?I'm assuming it goes on the bottom?
Yes, the flat tab pokes through the hole in the case and snaps into place.
Mark
Mark
I wondered who bought that hedge trimmer off ebay?! Cool toy.
Ed ive had a couple of those barbs break also. Only 1 leaked though. Ive also had 1 furl tank leak at the seam on that mini mac style tank. It looked great, put it together and fuel everywhere. Back apart and nothing noticeable. Fueled it up with the front cover off and found it. Luckily mini tanks are everywhere and i had a spare parts saw. Crazy design in those mini saws.
Ed ive had a couple of those barbs break also. Only 1 leaked though. Ive also had 1 furl tank leak at the seam on that mini mac style tank. It looked great, put it together and fuel everywhere. Back apart and nothing noticeable. Fueled it up with the front cover off and found it. Luckily mini tanks are everywhere and i had a spare parts saw. Crazy design in those mini saws.
Ed, that is the o-ring I replaced years ago when it first leaked.
Ron
Ron
That's why I took it off the broken adaptor.
I looked in my tote of odds-n-ends & found another adaptor with a fuel line on it.I thought I'd seen it a few months ago,but wasn't quite sure.I believe it came off a MM25 that I bought for 99 cents,Lol.I didn't trust the fuel line,so I pulled it off.The O ring didn't feel quite right either,almost a little dry rot to it,so I pulled that off & put the O ring on that Ron used for replacement.I added fuel after connecting the temporary line to the carb & yee haw! - no leaks.Now I can only hope that the oiler on the replacement tank works.There was a lot of sludge in the oil opening & I cleaned it out the best I could with a Q tip.
I got sidetracked with another saw that came via UPS (sorry it wasn't a Mac).
I got sidetracked with another saw that came via UPS (sorry it wasn't a Mac).
I think you can be forgiven ed. Lol
Happy New Year everyone!
HAPPY NEW YEAR ALL!!
(By the way it's halfway through New Years Day here.)
Interesting find today while Inventorying in MacHall. It came from the factory this way. A NOS PM850 cylinder with the crankcase painted DE80 Black. Its a first for me. I know at the end McCulloch was slapping parts together on the replacement part side which I have seen before with cylinders.This just reinforces my long time belief that the "mated" cylinder and crankcase importance just isn't.
I have a couple NIB PM850 or SP81E cylinder/crankcase/piston kits in the attic marked 214716 with black oil tanks.
And this one that I found in a saw I was working on...
This one in particular was set up for either points or electronic ignition.
Mark
And this one that I found in a saw I was working on...
This one in particular was set up for either points or electronic ignition.
Mark
Though my experience is rather limited, I previously reported an incidence where an interchange of cases would not seal. I recall it was a DE80 crankcase to a PM800 cylinder. I recall that someone else posted an issue with a DE80 case. Probably both machining flukes; I have had no other interchange issues.
Ron
The only time I've had an issue with swapping cylinder and crankcase components (at least that I can recall) was a DE80 as well. Could be you were thinking of me Ron...
Mark
Mark
As I continue to organize the cylinder assembly's and log them, I will create a list of the late McCulloch part numbers on them. My helper and I spent 1.5 hours yesterday chasing a MM part number for a cylinder Them rascals have as many number variations as there were models of them lol
BTW @heimannm the cross reference information you provided me with has been invaluable. TY
BTW @heimannm the cross reference information you provided me with has been invaluable. TY
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