Mac 550 parts

[Madsaw]

Mornin All
Just picked up a MAc 550 night before last. Man is that a monster to pull over. No problem with compression there. Well the fuel tank looks like some on toke a dump in it. SO that needs cleaned. But, I have a feeling I may need to rebuild the carb. Is there any carbs from other size macs to replace the the pump primer carb thats on it. I got a bunch of 1-40 series saws sitting aroound for donors. Would like to get this one up and running. Is there alot of the 550 around. I see on mike's its a 100cc saw might be a fun one to play with. Or should I just sell it/.
Later time to pull cows
Bob

 

[Al Smith]

It's a big one at 6.03 cu in.According to my micros,in addition to that infernal flat-back,it is listed as having a Tillotson HL series carb.I can't really say as to the rarity of this model,which seems to be a regional thing.An example would be the fact that Mac 125 s are rare here,but rather plentiful in Pacific north west,and a 250 is common as dirt around here.I had a little match with a flat-back,which I won,but it was a challenge.These things have parts in them,that look like they don't belong in a carb for a saw.The diaphragm,and gas shut off,are huge,with respect to a normal carb.They seem to run fine,once they are properly set up.The Mac numbers are #66442,for the fuel pump,and #55067C,for the main diaphragm.The shut off lever is set at flush,to -.010 ,with the body.Try giving it a good cleaning,and set it up,it may work.