MacCat problem

[dubber]

I picked up a McCulloch MacCat at a garage sale for $5 knowing it didn't start. Since I'm unfamiliar with chainsaws I figured it would be a good learning experience. Originally the saw wouldn't start and the starter rope was very hard to pull. I ripped the saw apart cleaned everything, replaced spark plug and fuel lines, put it back together. Started up and idled no problem. Patting myself on the back I went in thinking everything was fixed. Next day I tried to start it again just to be sure - started no problem, but when I released the throttle to let the saw idle it died immediately. I also noticed a lot of oil buildup on the muffler. Through some research I concluded that oil from the automatic oiler was leaking back into the engine causing my problem. $28 later I replaced the oil pump but am still experiencing the same problem. Starts OK runs at full throttle, but dies at idle. Anybody know what's going on? Is the oil builup on the muffler normal or not? Help is much appreciated.

Mike

 

[treeclimber165]

Did you adjust the carb?

http://www.madsens1.com/sawtune.htm

 

[Rick Stafford]

Is the O'ring behind the oil pump good ?? If its bad it will let oil get into the cylinder through the impulse hole.Until the saw is ran for awhile the oil won't "burn" out.But I must ask as well, did you try to adjust the carb yet ??

 

[dubber]

MacCat problem follow up

The only adjustment I made to the carb was to seat the screws and then back them out one full turn like the manual said. I will try and adjust that this weekend. Also the manual said to mix the gas oil mixture 40:1 if using McCulloch oil otherwise mix 20:1 using any other oil regardless of what ratio it says. That's what I did. I bought 40:1 oil and mixed it 20:1. Could that be causing the problem. Why does the manual say to do that?

Thanks.

Mike

 

[Rick Stafford]

I personally use "ECHO" AT 50:1with 89 octane or better fuel or the other oil I would recommend is "HUSQVARNA PREMIUM" oil at 50:1 again with 89 or better octane.I'd try either one of those and that could cure your oily muffler problem and could possibly help your diaphrams in the carb work "EASIER" !!!

 

[sedanman]

dubber, Almost all manufacturers had the same line about mix ratio. They all want you to beleive theirs is best so you need more of the "other" stuff to get the same protection, and theirs is more economical to use since you need less.....B.S.! Mix up some 40:1 or even 50:1 and let 'er rip.

 

[John in MA]

Good to see you found your way here. These guys are right about the olil/gas ratio. These days just use whatever the maker specs for their own oil.

I'd still stand by what I said on the Wreck about carb rebuild and adjustment. It's the most common thing with any saw. If it's old, it needs it.

After that, I'd go after the oiler. These had a problem leaking into the crankcase, sometimes hydraulically locking the engine.

 

[dubber]

OK guys - went to adjust the carb last weekend as was recommended here. Saw wouldn't start at all. Verified the spark plug was working so I guess that narrows it down to not having fuel. I basically have three scenarios: saw starts and idles fine, saw runs at full throttle but stalls at idle, and saw doesn't start at all. I guess its probably the carb Can I just try cleaning it? What does a rebuild kit consist of and where can I find one for that saw.

Thanks again.

Mike

 

[sedanman]

Carb kit has new needle,lever, diaphragms, gaskets, screens etc. Diaphragms are most likely stiff or curled. Kits are sold by carb model not by saw model.

 

[radman44]

Its works

Just to let everyone know,
I purchased a mcculloch mini mac 6 for $5.00 from a yard sale that didn't start. First, I tried priming it and it took right off, until it ran out of prime. I tore it apart and rebuilt the entire machine, didn't find anything wrong so I put it back together. Still no success. I read the info here, and decided to get a carb kit. I went to manufactures supply and ordered all the parts for $10.00.
After I put the new carb kit in, did some carb adjustment on the jets (all the way down and 1/2 turn out) and it runs like a dream!
I would like to thank all the pro's here on this website, they were very helpfull.
Richard