McCulloch Super Pro 81

[stinkbait]

Update

I installed the new piston and rings onto the connecting rod tonight. Then I traced the exhaust port onto the piston skirt to see if I could widen it anymore. There wasn't a lot of room left, but I did widen it some and clean the rough casting marks up alot. I did not raise or lower the exhaust port any.

I also assembled the cylinder and crankcase and installed the oiler.

I made some gaskets too.

 

[little possum]

2 piece connecting rod?

 

[stinkbait]

2 piece connecting rod?

Yep. All the 10 series saws have them. The big end has 20 needle bearings. The little end has none. The piston has two caged needle bearings and the pin is a press fit in the little rod end with no retaining clips.

 

[rwoods]

Looks like you polished the intake. Did you? If so, did you also enlarge it? Ron

 

[stinkbait]

Looks like you polished the intake. Did you? If so, did you also enlarge it? Ron

I did enlarge it some, but mostly just cleaned up the casting marks.

 

[rwoods]

Did you press the wrist pin or tap it out/in with something? I'm trying to figure out what I'll need to line up to do mine. Thanks, Ron

 

[stinkbait]

Finished

Pressure tested the engine tonight and finished assembling the saw. I put a black starter on it off of a 10-10 because it looked better than the original one. I did a compression test and got scared because it only read 105psi. I soon found out that it was because the compression release was pressed. With new rings and piston cold it has 160psi compression. I'm happy with that. It feels like 200psi with that little starter handle. I will probably try and start it tomorrow.

 

[stinkbait]

Did you press the wrist pin or tap it out/in with something? I'm trying to figure out what I'll need to line up to do mine. Thanks, Ron

I used a clamp and two sockets.

 

[rwoods]

I used a clamp and two sockets.

I like the way you think. Good looking saw. I hope it runs well. Do you have any seat of the pants baseline to judge the result?

 

[Modifiedmark]

Mitchell, it looks very good.

Bet it runs as good as it looks also.

 

[rwoods]

Just read your saw list. Let me know how it compares to your PM800 which I assume is stock. Ron

 

[stinkbait]

I like the way you think. Good looking saw. I hope it runs well. Do you have any seat of the pants baseline to judge the result?

Thanks. I don't have a baseline though to compare it to.

Mitchell, it looks very good.

Bet it runs as good as it looks also.

Thanks!

Just read your saw list. Let me know how it compares to your PM800 which I assume is stock. Ron

My PM800 doesn't run at the moment needs a few parts (muffler, coil, carb kit, fuel line, and a few other things). Maybe I will get it running some time.

 

[thomas72]

I could use a fuel tank if you do not get the pm800 running .

 

[heimannm]

Nice Mitchell, If you have any left over 81/800 pistons let me know, I have a couple of projects up on a high shelf.

You really seem to have knack for the classic McCullochs, love the yellow and black they way you do it.

Mark

 

[rwoods]

My PM800 doesn't run at the moment needs a few parts (muffler, coil, carb kit, fuel line, and a few other things). Maybe I will get it running some time.

Then it's no contest, your SP81 will no doubt out run your PM800.

I'll look forward to your in the wood report. Ron

 

[stinkbait]

I plan on cranking it tonight, but I probably wont be able to make a video until this weekend. I have a 30" oak that I cut down 2 saturdays ago that I can test it on.

 

[stinkbait]

Oh one thing that I couldn't figure out was that this saw didn't have a ground wire connecting the engine to the isolated tank and handle. This matters because if the tank isn't grounded to the engine then the kill switch will not work. I had a spare ground wire from a 125 that I put between the engine and the lower handle. Now the switch works great. I don't know how it ever worked before.

I have a 16" bar on it now, but once I get it going and tuned I'll install my new 28".

 

[Duke Thieroff]

That turned out nice man, can't wait to see the vid.



Chris

 

[stinkbait]

That turned out nice man, can't wait to see the vid.



Chris

Thanks! Getting ready to go fire it up for the first time in a few minutes.

BTW that black recoil is one that came from you.

 

[stinkbait]

Well I fired it up for the first time a few minutes ago. The saw runs good and the acceleration is amazing. I do have a throttle linkage issue that will have to wait til another day. The linkage from the trigger is not letting the butterfly close completely. I also installed my new 28" bar and chian. I wish that I had one of those aftermarket west coast toothy things to put on it though. The stock one seems a little small.