Won't Start when HOT

[Holler Dave]

I use a 2.0 Mac w/14" bar for limbing. The saw starts cold on two pulls every time but if she runs out of fuel, she's done for a while. No matter what starting technique I use, she wont fire. Please don't tell me to get another saw cuz I love this little girl for the small jobs. It's getting to be a hassle to refuel and reoil it when running (yes, I'm very careful when I do it) Any of you pro's have an idea why she's so ornery when dry? Thanks. Holler Dave.

 

[slabberman]

G'day Holler,

I had a saw like that once, a Husky 50 (?) from memory, if she died once hot, you didnt even try it for an hour! Sorry to say, the best remedy I found was to get another saw!
Im sure you will get a better answer than this!!
Cheers
Charlie.

 

[eyolf]

I am afraid the advice you've gotten is probably wise. If your saw dates from before the bankruptcy, getting parts may be a real bear. If newer production, it may still be hard. The Asian concern that bought some of the tools and stock with the trademarks has no intention of supporting their purchase with service beyond what the law requires; that means that defective units sold at the present time will be traded for new product...if the store where it was purchased will accept it back.

There can be any number of reasons why it does this;
carb problems, even including vapor lock
Low compression (worn) engines start and run good when cold but not hot.
Magneto/ign problems related to heat.

A good repair shop could find out, but those little saws are often hard to work on, and expensive. When you can get another one on Ebay for $50 or less, why spend very much fixing one?

 

[builder]

I had a 4cube mac that did the same thing,started when I had less than 10 hours on the saw,tried everything,finally decided it just ran hot due to poor design.later macs just weren't meant to be used very hard,built just well enough to get out the door.I know this isn't what you want to hear but unless you're working for McD's it's not worth your time.run it out if you must,just be careful with the hot refuel!

 

[Rick Stafford]

It sounds to me that you should try a better grade of fuel.I'll tell ya one thing thats a sure way to find out if its vapor locking;Go to a small airport and get some aviation fuel,lowest octane aviation fuel and mix it with your 2-cycle (prefferably echo or husky premium),and see if it will restart when hot.Aviation fuel is a good ol' fuel without all the "CRAP" that they put in at the pumps.Besides when I run aviation fuel I get more hours per tank so it's kinda worth it.Now I know there are goin to be comics out there that say its not worth wasting your time or money on the old worthless yellow machine but I'm kinda fond to em myself !! ,

 

[Dagger]

Stafford's givin you good advice..id be on the trail of better fuel first also, although maybe not AV-GAS..maybe SU 2000 shell of AMOCO Ultimate...try this with good oil...readjust the carb and make sure its not too lean..or just tweak the low speed jet out jus a tad for richer starting!

on old Macs another trick to help em start better was to raise the metering lever jus a tad..maybe the thickness of the tab is all, to give the diaphram a stronger pulse..but readjusting the carb correctly will follow and is a must!..if this is past your abilities..then take it to a dealer with a good shop man..!

 

[hermit]

macs

I owned 1 and only in 1963. It wouldn't start hot. Sounds like they are still junk. I would put gas in an oil squirt can and squirt it in the muffler, that would usually work then I bought a HOMELITE and after about 10 years or so Echo it does the job. I do not make a living using a saw now.

 

[Methoss084]

Sounds like maybe a bad metering diaphragm in the carburetor, maybe? If you search enough you'll come up with parts for it on Ebay. I think the 2.0 had an MDC carburetor on it. With shop rates approaching $60-$65 an hour in the Northeast I've seen alot of those saws end up as scrap.

 

[tony marks]

had the same problem with my poulan pro 260 which i bought
to replace my 028 that was stolen. vapor lock.
by the way the 260 was stolen too.
they finally caught the whole bunch of thieves a couple o months ago. they all told on each other,after they caught a couple. thought that was funny.the sheriff was pickin up people all over 2 counties.

 

[rahtreelimbs]

hot saw won't start

I used turbo blue one time ( over 100 octane ) this stuff burned so slow that the saw accelerated real slow. Maybe some slight tweaking of the saw would have helped but I did'nt bother.