Porting an old saw

[isaaccarlson]

A customer just dropped off an old WD80 with an AH81 motor. It belonged to his dad. He has no idea how long it’s been sitting, and he wants it back in running order so he can use it. I have not taken it apart yet, but I am wondering if anyone makes parts for these any more. The cylinder looks like it might have some scoring. I’m also curious about cleaning up/reshaping the ports. Common sense tells me that if the motor has good bearings, a little work on the ports would be a good thing. I don’t know what these old saws will take as far as rpm, so I’m asking to see if any of you know. The tag specifies 16:1 mix, how does this translate with modern oils?

 

[Al Smith]

I think it'an older version of the Power Products AH 82 only slightly less displacement of nearly 8 cubic inches .I have two of them,one that is pretty much junk and another I did have running for a short while until I managed to loose the duck bill check valve in the original Lauson /Tecumseh carb .
I think in the day these were a generic type engine about like a Briggs and Stratton only in two cycle .More power per size and weight than a Briggs.They used the AH 47-58 and 82 during early go kart racing at which time aftermarket parts were every where .After over 50 years it's hard to say where any are these days --E-Bay maybe ?

 

[67L36Driver]

Use it? Seriously??[emoji15]

They don’t spin up fast but will pull a long bar with large chain.[emoji106]

Impressive shelf queen it would be.

Trade him a Farm Boss. Ask for boot.

He will get a lot more cut.

 

[isaaccarlson]

It’s a sentimental thing for him. I don’t even know if his dad ever ran it, it was just in his house in Florida. He looked them up on youtube and said he loved the sound, but wanted it to Cut a bit faster. I told him it would be about the same speed as a 50cc modern saw. It must weigh 35 pounds or so. Quite heavy for a working saw.

I’m just looking for info so I can decide how to move forward with this. He has a budget of $200, so I need to find prices for pars before I do anything to it.

 

[Al Smith]

If my info is correct it's got enough power .around 8 HP .It's one of those saws you fire up every so often,play around a little bit and put it back on the shelf .I have several of those types myself .
As far as souping it up the challenge with something like this is just making it run .

 

[Al Smith]

One more thing I might point out .Back in the days of two cycle karting there were three big names,McCulloch,Westbend and Power Products .There were also a zillon companies that made aftermarket parts to enhance them .The short comings of the Power products engine was a weak cylinder that on occasion came apart like a dollar watch .To alleviate that cylinder heads were tied together using long "banjo" bolts which you might find on old pictures .
In fact I think it was Horstman that made a cylinder head that was "slugged " .In other words had a protrusion that went into the cylinder which raised the compression that sealed with a piston ring .It also had "ears" to fasten the banjo bolts .

 

[isaaccarlson]

Thanks for the info guys. This one came to a screeching halt tonight. I started checking it out, and the flywheel wouldn’t make a full turn. It felt like something was keeping the piston from going all the way down, so I opened the bottom end. Everything looked ok, but it still didn’t want to turn. I looked down into the side of the rod bearing and couldn’t see the rollers turning and they looked strange. I removed the rod cap and found the problem. The needle bearings are smashed. I have no ides where to find a new parts. It would need a new rod, bearing, seals, and crank at the very least. If anyone knows where to find a new AH81 motor, I’m all ears. Otherwise this saw will get closed up and returned to the customer.

 

[Al Smith]

This may sound far fetched but needle bearings don't flatten out like they were made of lead .Thinking out loud it makes one wonder if at some time somebody tried to replace them with mild steel rod stock .
For example if say a universal joint hangs up on an automobile the needles will cut groves in both the joint plus the caps and the needles will still be perfectly round . These things are hard .

 

[CR888]

I hope the build/restoration goes well and you don't run into too many brick walls. Rare old saws are a tuff gig for customers on a set budget. I hope no more hidden surprises jump out! (but they will...)

 

[isaaccarlson]

This may sound far fetched but needle bearings don't flatten out like they were made of lead .Thinking out loud it makes one wonder if at some time somebody tried to replace them with mild steel rod stock .
For example if say a universal joint hangs up on an automobile the needles will cut groves in both the joint plus the caps and the needles will still be perfectly round . These things are hard .

Yeah, they just don’t look or feel right. I will see how hard they are.

 

[67L36Driver]

Not far fetched Al.

Break, yes. Mash, no.

I bet ten USD to a donut, someone parted off finish nails to substitute for bearing rollers. [emoji6]