OutdoorKing Repair Forum Forums Repairs and Maintenance Questions on Chainsaws and Concrete Cutters Petrol Chainsaws and Concrete Cutters Pioneer 620

This is my first piece of vintage machinery. I'm not sure what age dictates "vintage" but from what I have looked up, this machines manufacture dates are '62 to '64. It's a shame that it has lost its ID plate because they are a Canadian machine but apparently some were assembled in Australia and that is noted on the ID plate.

According to the seller this machine was run about 5 years ago just to see if it started and it did. Prior to that it had sat for about 10 years.

The only other saw of significance to me that I own is a Stihl 032AVe. It has oodles of compression. This saw seems to have more! It really takes a decent pull to spin it over.

Apparently they are over 100cc. It has a hardnose bar tip. The starter was sticky and didn't retract fully. I'm weird because that annoys me. It's the first thing I had to fix. A touch of lube on the spring and some light grease on the spindle has it working perfectly. A bit of grease on the roller for the cord guide and it's working very nicely.

The drive sprocket looks really good, very little wear at all. The magnesium is in excellent condition with no real signs of corrosion. Oil pump works too.

This machine is unique in that it has a glass fuel bowl, this one is even more unique in that it is missing. I am currently searching for one. The aircleaner is all there, screen, element and guard. The element is looking sad.

I'll give it a clean up, try and source the parts and then at least fire it up, cut a log and retire it to a display item in the shed. The second,behind the 032.

















The crud coming off this thing is amazing. Perhaps the thick oil muck is what has protected the cases all this time.

I do have a couple of questions. The top cover has three rivets at the front for a bracket on the underside. I can't see how it attaches to the front of the cylinder. It seems something it missing as all that is holding it is a screw at the rear of the top cover.

Second, this saw is a manual oiler. The oil pump works but the oil is pumps looks like used sump oil. It is very dark. If I ever get it running do you think that new age bar oil would be ok to use? I wonder if the heavy viscosity of bar oil will affect the pump.

Nice old saw..Most of the old guy's would use sump oil for bar oil,just give the oil tank a good fush to get all the crap out and it will be fine to run new age bar oil..

Thanks Chris.

What are the chances someone here has a manual or parts list? I found a wesite listing parts but they are just part numbers with no reference to the models they suit.

Aldo, I saw a couple of people reported they got 620 parts from this site:
http://www.rottmansales.com/

The machine is too old to be listed, but apparently they emailed the site with descriptions of the parts they wanted, and were able to get them that way.

There is a guy saying he can sell a download of the Pioneer service manual:
http://store.chainsawr.com/products/pioneer-chainsaw-service-repair-manual

That's about all I can find that might be useful. However if you haven't watched it already, you might take a look at this video:

Thanks Grumpy. Hopefully that manual will hold some part numbers etc. I read on another website that the saw owners manual has a list of illustrated part numbers but the thread dates back to 2008.

That video is great. I wish I had access to such a workshop. That finished saw looked a treat. I don't know if banging down with a bare hand on barrel studs whilst slipping over piston rings is a good business promotion ;)He did a great job though.

Here are a few shots of the oil pump and resevoir. As Chris said it was full of sludge. I cleaned it up and reassembled it with a new split pin. The old retainer was just a bit of tie wire.

Did you strip the pump itself and clean it out? I had a saw once that had been fed sump oil: the pump was half made out of plastic, and it was gutted. I'm sure your pump is a much better one, but if it is worn, now is the time to put things right.

From the reports I've read, that is a really fine collectors' saw, but way too heavy to actually use.

Hi Grumpy, I pulled the pump apart and the only real consumable is a rubber o ring. The pump still works fine. The rubber sump line and filter still seem to be ok.

I'll go slowly as I am unsure how bad a shape the carby is in. I'll see how many gaskets I need and if they are available.

I was going to pull the intake and muffler to suss the piston. Would you go further and check engine internals before trying to start it?

I guess I could pull the head to suss the barrel a little better. Going by the video you need pullers to separate the case. I don't have anything like that.

With the plug removed the engine rotates freely with very little play when rocking the crank back and forth.

I normally don't dismantle an engine without a reason. If the piston and rings are good (viewed through the ports) and the compression is good, I'd be looking for evidence of leaky crankcase seals or gaskets. Try to assess the main and big end bearings for slack by feeling for movement. If it came through all that evaluation well, I'd run it to see how it sounds and then start the tidy-up job on the carburetor and probably some other parts. I personally don't remove even cylinder heads routinely, I only do it for a reason. Those comments are for a mower engine. Chainsaw and brushcutter engines I am even more reluctant to dismantle because most of them seem to be made out of snap-on plastics and tin twist-tabs that will not survive servicing. I think your machine is of a higher calibre than that but unless it was part of a restoration, I'd only dismantle bits I had to service. For example, when you start it you'll see whether it is pumping bar oil. If it is, I wouldn't clean out the oil passages downstream of the pump, I'd let it clean them itself by pumping oil through them.

I understand that saw uses a fairly unusual design of centrifugal clutch, and with parts difficult to get, I'd begin by seeing if the clutch works. If it does, and its bearings are good, I think I'd leave it be for now.

I notice there is a chainsaw collector offering both illustrated parts list and service manual for your saw, if you send him a PM at another site. Read this thread:
http://www.chainsawcollectors.se/phpbb3/viewtopic.php?f=7&t=12190

I've no idea whether he wants money or not.

Thanks Grumpy, I'll certainly give that a look!

Grumpy that worked a treat. The IPL showed that I am missing a few other parts from there. Time to get out and search. Could be a while before the saw gets a run though.

Aldo, I've noticed from your threads over the past couple of years that you always seem to solve your technical and procurement problems once you focus on them. I'm betting you'll find those parts, either new or second-hand. As you say, it might take a while, especially if you have to go for second-hand ones.

Fellas I have managed to source a fuel bowl and metal retainer.



What I dont know about of have a clear diagram/picture of is what goes inside. I know there is a fuel felt/strainer/filter of some sort but not sure how. There seems to be a thread inside of the tallest of the tubes under the fuel bowl. Perhaps a cage or support for the gauze filter?? Not sure what would screw in there and can't find any detailed pictures.

Some more pictures just for reference







Aircleaner is made up of three sections. This cover, the element and a gauze screen.

Lookng good your getting there..There are many site's on chainsaw's you will get this saw to 100% trust me,It will just take a little looking and patience....Myself not that Ive worked on that many old saw's is the tool less High screw I myself have never seen this before and I like it....Carby looks like a tillotson and you can still get kits for them.....

The fuel in the glass bowl most likely enters from the center hole and exits from the outside hole, so that surplus crud ends up visible in the glass bowl, rather than underneath the filter screen. The filter is in between the two holes. AFAIK there were two usual types of filter for glass bowls on cars: in the later days, a paper one that just about took up the whole bowl space, and in the early days, a flat ceramic one that had a hole in the center. Normally the glass bowl hung underneath the metal part, and acted as a sediment bowl. For some reason yours is upside down, but on a chainsaw there isn't really an up and a down, they are used in all positions.

Being on a chainsaw rather than a car, your bowl probably used fine brass mesh rather than a ceramic filter element. It may have just been a circular screen, held down by the rubber washer, with a hole in the center for the fuel entry port.