McCulloch PM 610

[lot8con8]

I have a McCulloch PM 610 which is about 15 years old. The saw will start and run but will not idle. I am the original owner.

I have checked the piston and can see no scoring; compression is about 110. I have put a new carburetor kit (Walboro) on the saw, new plug, etc. The saw does seem to be spitting gas back into the carb.

Any thoughts on this; anyone seem to know what is happening or past experience.

Thanks in advance for any assitance.

Jeff

 

[Lawn Masters]

Does it just stall, or does it seem to run a little fast/slow then just die?

 

[Al Smith]

610 idle problem

This is only a suggestion,may work,may not.Set both the idle,and high speed jets about one and a half turns out.Set the low speed bumber at a position,where the saw will run[ it would be safer to remove the chain until you get it set up ].Back off the bumper until the motor starts to miss.then back out the idle screw until it settles down[ counter clockwise ,richer mixture].If it gets to "blurping"[like the choke is on],the mixture is too rich.If you can get it to idle,put the chain back on,and try it out.If it falters on acceleration,it is still too lean on the idle.If it reaches high speed then falters,it is too lean on the high speed jet.Walbro,Zama and Tillotson,all have good web sites for their carbs and go into a pretty good proceedure for tuning.It is a poss ible that the crank seals are bad.All this info as I said is just a stab in the dark on my part.Best of luck. Al

 

[rb_in_va]

Anyone looking for a Mac 610 parts saw? Here's one on ebay cheap.

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=20538&item=4304165568

 

[lucky]

Here's a pretty good link that may help with the tuning process.

carb adjustment

 

[Al Smith]

pm 610 carb problem

lot8con8;Here is a little update that might held you with your problem.This morning,I installed a carb kit on another persons pm 610.I used a kit that I got from MSC.[Walbro ]The original problem was the saw would not start,after setting for a while [ stiff diaphrams ].After installation of the rebuild kit,It would not respond to high adjustment,on the screw,in other words the high speed had no effect on the speed,or rich ness.After a more carefull inspection of the new parts,in seems the circuit plate gasket,was not only thicker that the original [required resetting the shut off valve] but also was incorrect in that it had completely shut off the high speed circuit.I usually check the parts more carefully,before I install them I hope this info will be of help. Al

 

[Lawn Masters]

So Al, What you're pointing out isnt all your own fault, its partly factory error, from what I've read but I could have misread something too. I have similar problems with a carb on my Homelite BX90 blower, which ran fine last year when I took the engine apart for cleaning and now I have issues getting it to pump fuel to the engine, it comes out the air filter cover instead of going into the crankcase even after I put new gaskets in it. Carb repairs are a PITA for me.