Pro Mac 850 project

[promac850]

When I read this and without ever having read your profile, I thought that you just had to be from Michigan.

Chris B.

Lol, really? :msp_lol: Yeah. Meijer's is a nice store, I hear everyone else in the country really wants a Meijer's store. Unfortunately, I don't think the Meijer family wants to or ever will do such a thing. Wall-to-wall mart, however, is a parasite that must be destroyed! Then replaced by Meijer's, IMHO.

 

[promac850]

Got a lot done today... I put the carb and related crap back onto the handle/tank/top of saw thingamajigabob and also popped an orange Stihl filter into the end of the fuel line.

Airbox with carb, fuel line, and much more stuffed into it...

Fuel filter... sorry about blurry photo, my retarded camera decided to make it blurry. Notice I did not cut the fuel line... all I did was remove the washer that was inside the bell (lack of better term...) on the end of the fuel line so the Stihl filter could slide in far enough to stay put.

The blue choke and green oil buttons were swapped with the black ones from the original tank, as to prevent the spawning of a frankensaw.

The buttons...

And here we have the airbox lid... notice it says Pro Mac 850 on it... wait... You probably already knew that...

Also, I polished the top of the piston with 800 grit sandpaper and 15W-40 motor oil. It looks scratched up, but it really is smoother than a baby's butt. I just hope that speck of carbon in the middle of the piston doesn't come back to haunt me.

 

[ChainsawmanXX]

Got a lot done today... I put the carb and related crap back onto the handle/tank/top of saw thingamajigabob and also popped an orange Stihl filter into the end of the fuel line.

Airbox with carb, fuel line, and much more stuffed into it...
View attachment 174757

Fuel filter... sorry about blurry photo, my retarded camera decided to make it blurry. Notice I did not cut the fuel line... all I did was remove the washer that was inside the bell (lack of better term...) on the end of the fuel line so the Stihl filter could slide in far enough to stay put.
View attachment 174756

The blue choke and green oil buttons were swapped with the black ones from the original tank, as to prevent the spawning of a frankensaw.

The buttons...
View attachment 174755

And here we have the airbox lid... notice it says Pro Mac 850 on it... wait... You probably already knew that...
View attachment 174758

Also, I polished the top of the piston with 800 grit sandpaper and 15W-40 motor oil. It looks scratched up, but it really is smoother than a baby's butt. I just hope that speck of carbon in the middle of the piston doesn't come back to haunt me.
View attachment 174759

I dont think your gonna have any problems with The carbon build up on the cylinder.

 

[promac850]

I dont think your gonna have any problems with The carbon build up on the cylinder.

I was thinking a little isn't gonna hurt it, and I did get a lot of it out by boiling the cylinder, so it should be fine. (knock on wood)

 

[ChainsawmanXX]

I was thinking a little isn't gonna hurt it, and I did get a lot of it out by boiling the cylinder, so it should be fine. (knock on wood)

Sounds good to me! you got this Yeller Saw fixed up pretty much, Now you need to get you a Stihl, Then a husky, Then a Jonsered, Yea... CAD Is bad haha

 

[promac850]

Sounds good to me! you got this Yeller Saw fixed up pretty much, Now you need to get you a Stihl, Then a husky, Then a Jonsered, Yea... CAD Is bad haha

Lol. Yep. CAD is good. Better to piss money on saws rather than on saws. :yoyo:

 

[stinkbait]

Is it running yet?

 

[8433jeff]

Is it running yet?

Evidently not.

 

[promac850]

Is it running yet?

Almost... I've still got to go to a hardware store and get a heli-coil for the bolt hole that was screwed, and still have to clean some more parts off, then I have to assemble the crankcase and go from there. Don't worry, I'm getting there. I have all of next week off... spring break. I will get it done soon. (knock on wood)

P.S. I will be working on it more today.

 

[promac850]

I got a little bit more done, but now I have to go see the eye doctor. I got some kind of weird problem with it... j/k... No, really, just getting a check-up on me eyeball health.

I am a bit confused and unsure about this...

As you can see, there is that shiny circlular piece of metal... is that the check valve, or there supposed to be a check ball? I did not find a check ball in the bag. Anyone know?

As for the cylinder... I put the decompression valve on.

 

[promac850]

Just to be sure I do this rebuild right, do I need to hone the cylinder? (think 800 grit) Would that be a good idea?


I want to put the engine together soon, either tonight or tomorrow. If anyone is wondering about that bolt hole, I am just going to buy some JB weld, fill it in, then drill and tap.

 

[rwoods]

I am a bit confused and unsure about this...

As you can see, there is that shiny circlular piece of metal... is that the check valve, or there supposed to be a check ball? I did not find a check ball in the bag. Anyone know?

It is the oiler valve. Item 52 of Figure 9 in the IPL I sent you. Ron

 

[promac850]

It is the oiler valve. Item 52 of Figure 9 in the IPL I sent you. Ron

Okay, that was my original thought. Just had to be sure before I put it together. Thanks for confirming that Ron!

 

[promac850]

Alright Mac fans... I got some more work done. I was thinking of putting the saw together, then remembered those little rubber washers that go on the four main bolts to prevent bar oil from getting into the crankcase... it would've been a mess, I bet, because the washers are quite worn.

Here is a pic... the part number is 62842, part name is: Washer, sealing... If anyone has a set of four of these washers they're willing to sell, I'll buy them.

Or would some well-fitting o-rings work just as good? I'm looking for the easiest and cheapest way, lol.


Here is the crankcase and related parts waiting...

Teaser pic... I'm currently looking for a small (think around 8"x8" sheet of 1/8" or 3/16") 4140 or 4130 steel.

What do ya'll think?

 

[rwoods]

Teaser pic... I'm currently looking for a small (think around 8"x8" sheet of 1/8" or 3/16") 4140 or 4130 steel.

What do ya'll think?

I am only guessing here but usually there is method behind an engineer's madness. If this is the case with the MAC factory spike then I would suggest you maintain the same ARC as the original. In other words, it looks like your top spike is too long or the others are too short. Once again just a guess on my part. But in theory you do want the saw to rotate smoothly from point to point as much as possible. Ron

 

[promac850]

I am only guessing here but usually there is method behind an engineer's madness. If this is the case with the MAC factory spike then I would suggest you maintain the same ARC as the original. In other words, it looks like your top spike is too long or the others are too short. Once again just a guess on my part. But in theory you do want the saw to rotate smoothly from point to point as much as possible. Ron

I tried to get it exactly the same, it looked quite close, just that the bottom, as you said, is slanted towards the front. I will have to tweak it. Last thing I need is trouble getting the saw to pivot.


Edit: I just remembered that the paper is not perfectly flat... Will post a better pic tomorrow. It was folded for ease of transport.

 

[stinkbait]

I would not hone the cylinder if you are not installing new rings. I always just reuse the same rubber washers that are on the crankcase bolts. I always take the same grey motoseal that I use between the crankcase halves and put a bead around the base of the bolt head on top of the old rubber washer just to make sure its sealed good.

 

[promac850]

I would not hone the cylinder if you are not installing new rings. I always just reuse the same rubber washers that are on the crankcase bolts. I always take the same grey motoseal that I use between the crankcase halves and put a bead around the base of the bolt head on top of the old rubber washer just to make sure its sealed good.

I am putting new rings in. What sandpaper and technique do you recommend for honing. I don't want to mess it up.

As for the washers, will do. Thanks for the tip.

 

[rwoods]

I tried to get it exactly the same, it looked quite close, just that the bottom, as you said, is slanted towards the front. I will have to tweak it. Last thing I need is trouble getting the saw to pivot.


Edit: I just remembered that the paper is not perfectly flat... Will post a better pic tomorrow. It was folded for ease of transport.

promac610, my eyes are much older than yours - you may have the design perfect. Ron

 

[promac850]

promac610, my eyes are much older than yours - you may have the design perfect. Ron

:blush: Thanks. I checked it just to be sure, and here are a few pics of the spike, laid out on a flat surface and with rulers to illustrate the slope/arc of the tips.

Again, I am looking for a 8"x8" or so piece of 4140 or 4130 steel to make the spikes, 1/8"-3/16" thick. Anyone has a piece they'll sell, pm me. Thanks.