Pioneer 1200A questions

[wrhackett]

I have one of these 1970s vintage saws, 58cc, that I've been cleaning and working on for a friend. The engine runs fine and has good compression.
A few questions:
1. Data sheet on Mike Acres' Chainsaw Collectors Corner says to use 16 to 1 mix ratio in the fuel. I use 32:1 premium full-synthetic oil in all my other saws (Dolmar 166, Husky 372 and 394). Is 32:1 OK for the Pioneer too?
2. This saw has about the weakest clutch I've ever seen and is the Achilles heel of the machine- it only has two clutch shoes and these don't offer much contact surface area against the drum, so the clutch slips badly and heats up, the chain bogs down in the cut, and the saw is about worthless for cutting anything but toothpicks. I have dismantled the clutch and cleaned it up good, no oil or other residues inside the drum or on the shoes. Is there anything else I can do, or is this just the nature of the beast?
3. Is the manual oiler the only way that oil is delivered to the bar? I mean, does this thing automatically oil, or not? (This thing has about the smallest oil tank I've ever seen. One of many features that make me realize how far chainsaw technology has evolved since the 1970s.)

Thanks in advance for any advice, and I know there will be some good advice from you all.
Bill

 

[PES+]

The 1200A had the automatic with manual assist

You may have a 1200 with 1200A parts as the 1200 was manual only.

There is a PDF IPL fro the 1200A

On this listing if you scroll down

http://www.acresinternet.com/cscc.n...4053f2dbb54adf3b88256b0000126c99?OpenDocument

Later clutches can be fitted to solve your clutch problem.

 

[wrhackett]

Pioneer 1200A clutch interchangeability

Thanks, PES+ I have downloaded the parts list off Mike Acres' site.
Your comment about changing out the clutch is interesting and I would like to try this.
Any idea which clutch assemblies from other models (or makes) might work?
I suppose the criteria would be to have the same thread gauge for the clutch, but an improved design of the shoe-and-drum assembly.
The more general question that I have asked in many other instances would be "Is it possible for me, the family-guy doofus, to figure out interchangeability of parts by referring to parts lists or other documentation, or is this something that only experienced service pros would know from their experimentation over the years?"

 

[wrhackett]

Pioneer 1200A clutch

PES+ I forgot to say that I would buy a clutch from you, if you have one available that you can recommend.

 

[PES+]

I need to dig into some boxes

There are a couple of Pioneer guys that come here that may have some stuff and ideas to hel you out too.

Can you take a pic of the clutch set up?

I bet the spring is slack and the shoes are worn out from dragging.

I have not worked on one of those in a long time but I did swap the clutch out for the same reason......the small contact of the two shoes into the drum.

The IPL only gives part numbers which is of little help to me now.

I lost a whole bunch of Pioneer paper when a dealer I worked at died and the place was padlocked

 

[wrhackett]

1200a

I can take a photo, but may take a while to figure out how to post it here.
This saw hasn't been used very much, from the look of it.
The clutch springs and shoes seem to be in good shape. Springs are nice and snappy; shoes don't have much wear.
I could caliper the reverse-thread crankshaft diameter and use my thread gauge to get the pitch, if this informaiton would be useful as well.
Thanks for trying to help, PES+

 

[PES+]

The dimensions will work.......I am almost positive I swapped the two shoe for a three shoe from a Farm Saw....and I have those clutches.

 

[wrhackett]

1200a

PES=, please give me a day or so to make the measurements- other stuff has come up around here and I can't dismantle the saw right away. I can do it tomorrow morning (Saturday 3/29), and I will post the results.
Thanks again,
Bill

 

[wrhackett]

1200a

OK PES+ here we go:
The crankshaft is not reverse threaded like most modern clutches. Rather, it has ten grooves that have been cut parallel to the shaft axis. The outer diameter of the crankshaft in the area where these grooves have been cut is 0.448 inch.
The double-shoe clutch assembly slides straight onto the crankshaft and is prevented from rotating by mating with these grooves. Then there's an outboard cover washer (sort of like a big fender washer), and finally a normal-threaded nut on the outside that holds the entire assembly onto the crankshaft. Like the picture in the IPL.
As for the clutch drum, it runs on a needle bearing in the usual fashion. The inner diameter of the drum where it is contacted by the shoes is 2.832 inches. The inner diameter of the drum where it encloses the needle bearing is 0.627 inch. The diameter of the crankshaft under the needle bearing is 0.502 inch.
Please let me know what you think.
If you want to take this off the forum, my email is [email protected].
I am set up with Paypal (user name wrhackett), but other arrangements are also possible.
Thanks again for taking the time to help me work through this. The guy who owns this saw is a good friend of mine and I know he would be delighted to have it up and running. I think we're almost there.
Bill

 

[PES+]

Yes.....I did remember correctly

The Farmsaw clutch fits it........

Got you covered.

PM sent