Mcculloch 797, Super 797 thread

[Sloa]

Paint is fine, there are some things you doesn’t want to paint, but they ar minimal, I would replace the bearing and seal when apart! I have reran the outer “dust” seal but not the inner. I know it contrary to many, but I will often delete the points a dust seal and pointd box cover on the 125cc saws, I have great luck with a chip. I personally feel they rpm better. Point work, and running all the oem stuff is great too! Have several great running point 125cc.

Thanks Bigmac, I have a few extra point sets and I’ll tape as best I can, fit in place so no paint in holes or under points in case metal to metal needs to happen. If I cause no damage to dust seal when prying out inner seal I’ll do exactly as you suggest, makes sense and will fill any rough or deteriorating edges around dust seals o.d. Really good spark when first received saw so will continue with points .

 

[Sloa]

Late here , hoping to ask a few questions before I turn in. First of is the stuffer plate, what’s with circles and should I JB weld plate. Stuffer gasket.20 and seems to clear. Is this enough clearance or should it be doubled.
forgot how heavy engine is assembled, playing find a piece for eight months and only dressing up the block.

 

[Bigmac]

That’s normal! If you are worried you can put some motoseal on the gaskets.

 

[Sloa]

That’s normal! If you are worried you can put some motoseal on the gaskets. View attachment 425801

Thanks Bigmac, I am not all that worried. Appears to be okay. But if I have to go back moto seal on oil side and jb on crank side. Seals I picked up months ago I should have looked a little closer as there was wear on outer rim . Hopping it holds fine as the inner lip was fine.

 

[heimannm]

I posted this in the McCulloch thread but thought I'd repeat it here just in case. I'm taking a 797 apart and have run into a problem getting the crankshaft out. The notch to clear the throw is located TDC but the piston and rod do not move up far enough to let the crankshaft past.





On the 125 that notch is offset making it fairly easy to get the crankshaft past the rod and out through the opening.



Is there carbon accumulated in the cylinder/on the piston of the 797 not allowing it to move fully out of the way? If so, how do I proceed???

Mark

 

[Maintenance Chief]

I posted this in the McCulloch thread but thought I'd repeat it here just in case. I'm taking a 797 apart and have run into a problem getting the crankshaft out. The notch to clear the throw is located TDC but the piston and rod do not move up far enough to let the crankshaft past.

View attachment 426906

View attachment 426907

On the 125 that notch is offset making it fairly easy to get the crankshaft past the rod and out through the opening.

View attachment 426908

Is there carbon accumulated in the cylinder/on the piston of the 797 not allowing it to move fully out of the way? If so, how do I proceed???

Mark

Soak it in seafoam to break up the carbon?

 

[heimannm]

Soaked it in Mean Green, apply a little gentle persuasion and I now have it out.



I will assume the carbon on the piston was the culprit.



Mark

 

[JT78]

Wow that's a lot of carbon build up. Saw probably seen a lot of hours? Or just set really rich?

 

[Woodslasher]

Wow that's a lot of carbon build up. Saw probably seen a lot of hours? Or just set really rich?

30w at 16:1 was a major contributing factor, I'm sure.

 

[heimannm]

Making some progress. I have a granite slab that I attach emery cloth to and use it to flatten surfaces before reassembly.







The Mean Green also loosened up the baked on stuff making clean up an easier task.





Mark

 

[heimannm]

I use some studs to help keep the gasket(s) in place as the tank is assembled to the engine.









Mark

 

[heimannm]

Oilers work.



Mark

 

[Jusgunn3]

Anyone have a good way to remove the clutch on these babies to get to the points?

 

[Bigmac]

Anyone have a good way to remove the clutch on these babies to get to the points?

Points are under the flywheel, there are two threaded holes for bolts, a steering wheel pulller will usually work or something similar

 

[jacob j.]

Anyone have a good way to remove the clutch on these babies to get to the points?

 

[Jusgunn3]

Thanks, guys!

 

[B Royals]

Hello everyone. I acquired a Super 797 this week, and discovered that it will need a new piston and some machine work. I've been reading all weekend, and this thread appears to be the best place to ask questions, although not frequented often. I have a small collection of McCullochs, but this is the first large frame saw I've been able to get my hands on. Here are a few pictures, the good thing is that it appears complete. It has the HL 103 carb, thick rings, cast boost port - not milled though.

 

[hacskaroly]

Hello everyone. I acquired a Super 797 this week

Hello and welcome to the forum. Cool about your 797, looks like it will be a fun project.

 

[B Royals]

Here is some pictures of the P/C. After a weekend of looking the IPL's of the early 797, S797, CP125, and 101 kart engines, I want to verify that I'm reading them correctly. It appears the simplest solution would be to find the proper oversize piston and put it back to stock. My question is for you all that have ran 123cc saws. Would it be worth milling out the boost ports, finding a windowed piston with corresponding rod, wristpin and boost cover? Is that all that would be needed to make it like an regular 797? Jeff

 

[hacskaroly]

My question is for you all that have ran 123cc saws. Would it be worth milling out the boost ports, finding a windowed piston with corresponding rod, wristpin and boost cover? Is that all that would be needed to make it like an regular 797?

@heimannm , do you have any recommendations/experience with this?