McCulloch Chain Saws

Arborist Forum

Help Support Arborist Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
Joe, I'm making the presumption that the tank is not leaking. I have run across a few 10 Series saws lately that leaked around the fuel line passage into the tank. They all looked to have shrunk for some reason.

I think that's my next move, to replace that fuel line even if it doesn't look bad. The thing is pretty old and it does seep around where it goes into the tank. If I still have a leak I'll probably have to take the tank top off and try to seal it again.

I noticed the carb only has one adjustment screw and an idle speed screw. The high speed screw is replaced by a fixed jet.
 
Last edited:
Nice looking parts, you could almost piece together a saw around those pieces!

Yep. I got them with the idea of keeping them 'just in case' my runner SP-81 ever needed them. Now I'm going to rebuild a second SP-81 with 'em instead.


aaron, you never stop amazing me what you'll pull out of your ass next.:msp_thumbup:

Thanks....I think.:D

These parts came to me out of the blue. An AS member contacted me because I had just gotten an SP-81. We made a trade involving a 'modern' orange saw that I had (gasp). Since then, a 'rebuilder' SP-81 came my way (also out of the blue) and these parts will go towards that rebuild. The NOS 24" Windsor bar that you've seen me run on my PM700 came out of the same deal that got me these parts.

I know where a kit like that is for sale. $150 with no piston. It's just the cylinder and case. I left it alone, that's a high price for me.

Joey

That is steep for what's there. Somebody will probaby pay it though. It'd take a good deal more than that to get my parts from me.......but that's mostly because I don't want to sell them...:D
 
Last edited:
I think that's my next move, to replace that fuel line even if it doesn't look bad. The thing is pretty old and it does seep around where it goes into the tank. If I still have a leak I'll probably have to take the tank top off and try to seal it again.

I noticed the carb only has one adjustment screw and an idle speed screw. The high speed screw is replaced by a fixed jet.

If you do end up replacing that line, check inside the old one and try to salvage the spring that may be in there to keep the line from crimping.
 
I have been successful in stopping those leaks by wrapping the fuel line fitting with a few turns of teflon thread tape, make a nice tight seal again.

This has worked for me on a few of the bigger 700/800 saws as well as several 10 Series.

As Ted pointed out, if you replace the fuel like make sure to save the "spring" inside as they are crucial to preventing the line from kinking when the line is attached to the carburetor.

I have also found that a leaking 10 Series tank (non AV models) can often be corrected by simply cleaning the junk off the top of the gasket down in the groove, they seem to be pretty forgiving. The later saws with the sealed tanks (AV models like the SP saws) are a different story.

Mark
 
If you do end up replacing that line, check inside the old one and try to salvage the spring that may be in there to keep the line from crimping.

I'm glad you reminded me, I'd forgotten about the spring. Same with the wrap. I had kinda thought it was something wrong with the carburetor because I hadn't noticed the leak until I started cranking on it.
 
Last edited:
Found the Problem Pro Mac 55

The problem was with the carburetor. It actually was on the fuel pump side and because I didn't pay attention to the pump gaskets, they were slightly different, one had a hole in it corresponding to the hole in the pump metal plate which is right in line with the fuel inlet. The fuel was going into the carb and right out the hole in the plate. I'm not sure what that hole is for because it doesn't seem to vent anything, maybe this being an old saw someone might have put the wrong plate on the carburetor. Anyway, I put it back together and it roared to life so I guess all's well..
 
The problem was with the carburetor. It actually was on the fuel pump side and because I didn't pay attention to the pump gaskets, they were slightly different, one had a hole in it corresponding to the hole in the pump metal plate which is right in line with the fuel inlet. The fuel was going into the carb and right out the hole in the plate. I'm not sure what that hole is for because it doesn't seem to vent anything, maybe this being an old saw someone might have put the wrong plate on the carburetor. Anyway, I put it back together and it roared to life so I guess all's well..

I'm happy it's running for you .. I think.

What carb is on there? IIRC, only the metering side cover has a hole in it, but fuel never comes out of there because the metering diaphragm 'seals off' the fuel flow and that hole is just to equalize air pressure.

So I am lost for the time being .... :msp_confused:
 
I've had some success with the teflon tape 'fix'. My SP-81 wouldn't seal with a brand new aftermarket line. Wrapped it with several wraps of teflon tape and it seems to be holding. I still think this is a stupid design however. I'm talking with a machinist about having bulkhead fittings made up for 10-series saw tanks. The section of the tanks where the line passes through is much thicker than the rest of the tank wall, so it ought to support threads nicely. A fitting that threads into the tank from the carb side and has a 1/8" barb on the inside and a 3/16" barb on the outside would be great. Of course we'd have to tap the tank pass-thru hole for the fitting.

Alternatively, a fitting similar to what's on earlier 700/800 series Macs (740, 790, etc) would work too. That has a threaded shank with a hex head on one side, while the other end is secured with a nut. Fiber (or nylon or copper) washers seal against the tank wall. The 700/800 series fitting has a 1/8" barb on the carb side and a 3/16" barb on the tank side. It could be reversed, but tightening the nut would be tricky on the sealed tanks. Would be a piece of cake on the two-piece tanks. Anybody here interested in getting in on a run of 10-series bulkhead fittings? I'd be in need of five of them right away, with more in the future. Let me know if you'd be interested in something like this. I need to tell my machinist friend what to expect in the way of interest...
 
I've had some success with the teflon tape 'fix'. My SP-81 wouldn't seal with a brand new aftermarket line. Wrapped it with several wraps of teflon tape and it seems to be holding. I still think this is a stupid design however. I'm talking with a machinist about having bulkhead fittings made up for 10-series saw tanks. The section of the tanks where the line passes through is much thicker than the rest of the tank wall, so it ought to support threads nicely. A fitting that threads into the tank from the carb side and has a 1/8" barb on the inside and a 3/16" barb on the outside would be great. Of course we'd have to tap the tank pass-thru hole for the fitting.

Alternatively, a fitting similar to what's on earlier 700/800 series Macs (740, 790, etc) would work too. That has a threaded shank with a hex head on one side, while the other end is secured with a nut. Fiber (or nylon or copper) washers seal against the tank wall. The 700/800 series fitting has a 1/8" barb on the carb side and a 3/16" barb on the tank side. It could be reversed, but tightening the nut would be tricky on the sealed tanks. Would be a piece of cake on the two-piece tanks. Anybody here interested in getting in on a run of 10-series bulkhead fittings? I'd be in need of five of them right away, with more in the future. Let me know if you'd be interested in something like this. I need to tell my machinist friend what to expect in the way of interest...

I'm in for 5 .... so long as I never have to split a fuel tank again ... :bang:
 
Hey Roland, caught you looking!

Aaron / Ted, I think you can put together what you want from two components in the McMaster Carr catalog, use a "through wall adapter" and then tap the I.D. for a straight adapter for the barb on the other end.

Cost would be around $12.00 for 10 sets of the fittings ($1.20 each) and your time to tap the "through wall adapter". I have had very good success using these kinds of nylon fittings for fuel lines on old saws, lawn mowers, etc.

For those wondering, I just ordered several different size through wall adapters as well as the straight adapters, I should be in business tomorrow night making up new fittings if anyone is interested in trying one. Just be sure to tell me what tubing sizes you want on either end.

Mark
 
Last edited:
I'm happy it's running for you .. I think.

What carb is on there? IIRC, only the metering side cover has a hole in it, but fuel never comes out of there because the metering diaphragm 'seals off' the fuel flow and that hole is just to equalize air pressure.

So I am lost for the time being .... :msp_confused:

No, it's the other side and it has 2 holes in it other than the bolt holes. They are on opposite sides of the plate, the larger one is right next to the inlet where the fuel line comes in. It's a Walbro SDC.
 
I've had some success with the teflon tape 'fix'. My SP-81 wouldn't seal with a brand new aftermarket line. Wrapped it with several wraps of teflon tape and it seems to be holding. I still think this is a stupid design however. I'm talking with a machinist about having bulkhead fittings made up for 10-series saw tanks. The section of the tanks where the line passes through is much thicker than the rest of the tank wall, so it ought to support threads nicely. A fitting that threads into the tank from the carb side and has a 1/8" barb on the inside and a 3/16" barb on the outside would be great. Of course we'd have to tap the tank pass-thru hole for the fitting.

Alternatively, a fitting similar to what's on earlier 700/800 series Macs (740, 790, etc) would work too. That has a threaded shank with a hex head on one side, while the other end is secured with a nut. Fiber (or nylon or copper) washers seal against the tank wall. The 700/800 series fitting has a 1/8" barb on the carb side and a 3/16" barb on the tank side. It could be reversed, but tightening the nut would be tricky on the sealed tanks. Would be a piece of cake on the two-piece tanks. Anybody here interested in getting in on a run of 10-series bulkhead fittings? I'd be in need of five of them right away, with more in the future. Let me know if you'd be interested in something like this. I need to tell my machinist friend what to expect in the way of interest...

I've had a little bit of luck with shrink tubing around the outside of fuel lines, you just keep layering it on until you get the build up that you want.
 
2014, 3516, 3200 etc. type coils.

They seem to fail for no good reason and there are none on evilbay. So, before you toss out the carcass save the coil.

I know they are not held in high regard but, just sayin'.

Mo. Jim just bailed me out on one that I sold to a homeowner.

Carl.
 
They seem to fail for no good reason and there are none on evilbay. So, before you toss out the carcass save the coil.

I know they are not held in high regard but, just sayin'.

Mo. Jim just bailed me out on one that I sold to a homeowner.

Carl.

I always save the coils and carburetors but sometimes I forget what they came off of. I guess they have numbers on them that would tell..
 
New page needs some photos

attachment.php


attachment.php


attachment.php


These were from storm damage clean up July, 2011.

Mark
 
Hey Roland, caught you looking!

Aaron / Ted, I think you can put together what you want from two components in the McMaster Carr catalog, use a "through wall adapter" and then tap the I.D. for a straight adapter for the barb on the other end.

Cost would be around $12.00 for 10 sets of the fittings ($1.20 each) and your time to tap the "through wall adapter". I have had very good success using these kinds of nylon fittings for fuel lines on old saws, lawn mowers, etc.

For those wondering, I just ordered several different size through wall adapters as well as the straight adapters, I should be in business tomorrow night making up new fittings if anyone is interested in trying one. Just be sure to tell me what tubing sizes you want on either end.

Mark


Mark

I really like your photos of saws. It would also be nice if you could show some photos of what
you are doing with the fittings.

ODW
 

Latest posts

Back
Top