Pinoeer 650 troubles

[Aussie MacGyver]

Howdy All

Just go an old (50 yrs old) Pioneer 650 saw. Looks the goods and has excellent compression. Damn thing wont run for me. I can get it to run for about 15sec by goosing the throttle and such but it wont rev past 3000rpm or so, nor will it idle.

I have pulled the carb apart and it all looks good. I've been messing with the H and L needles which got me as far as the above.

What would be half decent starting values? Like a car around 3 turns?

Any other suggestions?

I tell you what it is a bugger to try and start. 6 odd cui is a lot to try and pull start. I have muscles hurting I never knew existed! What is a good starting proceedure for big saw?

cheers
Scott

 

[retoocs555]

Have you replaced the fuel filter?

Are the muffler and air filter clean?

The carb on that saw is pre-dates the type of carbs used on more modern saws so I'm not sure where you would want to start with the H and L needles but, standard is 1 turn out from lightly seated for each, I would try that anyway.

 

[romeo]

Sounds like a vaccum leak to me, probably a crankshaft seal.

 

[Lawn Masters]

To make things simple, first of all, if you can, procure a rebuild kit for the carb. it may be as simple as stiff gaskets that just wont pump fuel anymore. they may look ok, but not be flexible enough to move the amount of fuel needed.

 

[Sprig]

I have to agree with lawnmasters sound carb advice on this one, especially in an old beast (my shoulders ache just think of starting that thing lol), in addition I would carefully check your line from the filter, as old as it is very often that rubber tube becomes 'soggy' and the saw will run up to a point then the line collapses, run into this a few times and a fairly painless fix with good plastic line and new filter (old water in the filter will do about the same thing), I'd probably give the tank a really good rinse as well, anyways its a good place to start to trouble-shoot yer problem. Good luck and let us know how it goes eh!

 

[Aussie MacGyver]

Forgot to add that it is actually missing the muffler. Would this contribute?

cheers
Scott

 

[Aussie MacGyver]

Should the glass sight bowl on top of the tank be full when running? Mine only ever gets about 1/8th full if that. I pulled the bowl assembaly off and the line into the tank was deteriorated. Replaced the line, but at the end there is a filter with 2 o-rings on it. Is this supposed to go a certain way into the tank or are the o-rings just to suppress rattles?

cheers again
Scott

 

[Aussie MacGyver]

Well I got her going!

I pulled the tank apart and resealed it as it was leaking a tiny bit. Screwed the H needle all the way in and L about 2 turns out. Took the air filter off and started her up. Was spitting a bit of fuel out the carb so wound in the L needle. Once I was happy with the idle I started to up the revs and slowly screw out the H needle. Found a nice balance for both and now the old girl screams.

Took her out back to chop up some fire wood. One pull on the starter and.......The cable broke

Some days you just can't win, can you?

So I guess I will redo the starter and chop some wood tomorrow. I can still hear her screaming away. Sounds great.

cheers
Scott

 

[Four Paws]

Make sure you pull the plug after 1 cut through a nice piece of wood. Make sure you shut it down at wide open throttle. You want to make sure the plug is a nice tan color. Make sure it is not black (rich) or white (lean). Usually 2 strokes will run absolutely wonderful (and extremely powerful) right before they lean-sieze. I just don't want you to melt the old girl down.

 

[Aussie MacGyver]

Well I just cut up 3 logs after fixing the pull cord. Seems to bog down every now and then and will only idle at a speed that keeps the chain running. I will do a WOT run and stop and check the plug.

As I wind down the idle speed she will eventually stall and then be a dog to start until I up the idle speed again.

Any ideas?

cheers
Scott

 

[ray benson]

Forgot to add that it is actually missing the muffler. Would this contribute?

cheers
Scott

Read in some of the Homelite repair manuals NOT to run the saw without the muffler.

 

[ozflea]

Most of the older saws i have come across need a pressure test of the crankcase to be sure that seals ain;t leaking, fuel lines and a carby clean seem to fix most of them. If the muffler is off then its easy to check the condition of the cylinder for scratches or grooves and if possible get a muffler for the old girl as it will help retain your hearing and ensure pleasant neighbours remain as friends.

Mc Bob.

 

[Aussie MacGyver]

Well it seems the more she runs the better she gets. Evrything is starting to settle down. Getting closer to a good idle, and have pretty good power. Pulled the plug after a good WOT run and it is a nice tan with a hint of grey. I have richened the WOT mixture up a tad.

cheers
Scott