Anything specific or different to know about cleaning a 2 cycle fuel system?

[ebinmaine 67,502]

I've learned a lot in the last couple years thanks to all of you and one of the next things I need to educate myself on is cleaning and replacing lines and filters on a McCulloch trimmer.

The symptom and reason that I am doing this is that it will only run on half choke. Open the choke all the way and it dies almost instantly. That would tell me that I have issues in the fuel system, I suppose.

 

is there any particular thing or part or whatever that I need to pay particular attention to?

 

 

[Achto 27,577]

With out knowing your particular engine I'll give it a shot.

A lot of small 2cycle engines will have a diaphragm pump inside the carburetor. Over time these dry out & can cause the symptoms that you are having. So I would find a rebuild kit for it .

 

Pay close attention to the adjustment screw settings on the carb when you disassemble it. You'll want to get these back to the factory settings. A slightly rich fuel mixture is much better than a lean mixture when it comes to a 2 cycle. A lean mixture will burn them up in a hurry.   

 

Other than that cleanliness is king.

[Digger 66 3,478]

Whatever you do , don't dilute a ( guessing 40:1 ) mix with Seafoam or some other snake oil crap in an attempt to clean the carb..

Achto gives good advice in paying attention to the high / low speed Idle settings if so equipped .

Take a pic of the screws then turn them in one at a time counting the revolutions until lightly seated then write down how many for screw "A" / "B" etc .

Other than that , take some more pics ( if it's your first time ) , lay some newspaper out and DIG IN .

Let's see a pic and watch for serial numbers on the carb . Many times these can be had on E-bay for under 20 beaver pelts .

Sometimes it's just better and more economical to replace than rebuild .

 

Other advice which I have ...

The air filter should be rinsed with kerosene or some mild solvent then re-oiled and patted dry .

Fog the motor in the fall and empty the tank .

Buy the premixed fuel from Home Depot or wherever .

If not use Non E fuel and a name brand oil .

An ounce of prevention is worth a pound of cure and I'm not just saying that .

When I bought my house in '96 I bought the same Ryobi trimmer I'm using today .

 

 

 

 

Edited September 13, 2018 by Digger 66

[ebinmaine 67,502]

20 minutes ago, Digger 66 said:

Fog the motor in the fall and empty the tank .

Buy the premixed fuel from Home Depot or wherever .

If not use Non E fuel and a name brand oil

Thank you both.

What does it mean to "fog the engine" ?

I've heard the term...

 

I  ONLY use non ethanol gas in all my tractor and small engines.

 

[Digger 66 3,478]

Fog it means to remove the air filter and run her wide open while spraying fogging oil into the venturi until she dies .

Stabil fogging oil can be found at Wal Mart in the engine oil / fuel cleaner section .

Then clean or replace the sparkplug in the spring .

https://www.walmart.com/ip/STA-BIL-22001-Fogging-Oil-Cylinder-Protector-12-oz/41241735?wmlspartner=wlpa&selectedSellerId=1122&adid=22222222227028832777&wl0=&wl1=g&wl2=c&wl3=61671408129&wl4=pla-97838191449&wl5=9005556&wl6=&wl7=&wl8=&wl9=pla&wl10=101593696&wl11=online&wl12=41241735&wl13=&veh=sem&gclid=CjwKCAjwlejcBRAdEiwAAbj6Kd-tdX_SWi-7124MZDndBoO_umrRpJfH8gTQNjaHn9ei6pl0b_n7ExoCmBIQAvD_BwE

Edited September 13, 2018 by Digger 66

[Digger 66 3,478]

I'm still running this relic of a chainsaw my Dad gave me 

 

[SylvanLakeWH 25,560]

Have you tried a shot of carb cleaner?

 

Also run them out of gas before you store for the winter...any residual in the carb will gunk up with the oil mix...

 

I always disconnect the line and run 2 strokes dry for storage over winter...

 

[WHX?? 48,815]

Geez you guys are getting awful technical.....I usually just wind them out till something snaps and ....go buy a new one?

Just kidding..... I have been using the fuel in a can in the 2 strokes. Shelf life is ungodly and really does help with overwinter starts. No need to drain.

If I know I am going to go thru a full tank in a use I just run hi test with the appropriate amount of oil mixed. Just to cut down on the expense of the canned. With the canned stuff you wonder does this crap even have any oil in it? No problems so far. 

[ebinmaine 67,502]

6 hours ago, SylvanLakeWH said:

Have you tried a shot of carb cleaner?

No but it's time for a tune-up anyways.

It's been several years since this machine has been tuned right.

Fuel filter is at the end of the tube so I'll just replace it all.

 

I do normally run the fuel to stall out from all my small engines but this one sat with gas in it all winter.

[Pullstart 62,883]

Anyone ever heard of auto trans fluid as a fuel system cleaner?  My auto shop teacher taught me that.  A quart in the gas tank of a vehicle, or a couple cap fulls in the intake, or 2:1 replacement of 2 stroke oil in a gas/oil mix.  I’ve done it for nearly 20 years and haven’t ever had an issue.  Trans fluid is super rich in detergents and still lubes well.

Edited September 21, 2018 by pullstart
Auto correct...

[ebinmaine 67,502]

Back in the days when engine oil wasn't capable of holding dirt like it does now I'd seen a few sets of heads all gunked up from lack of maintenance.

I've not personally done it but have heard of using atf as an oil flush cleaner.

 

[WVHillbilly520H 10,373]

10 hours ago, pullstart said:

Anyone ever heard of auto trans fluid as a fuel system cleaner?  My auto shop teacher taught me that.  A quart in the gas tank of a vehicle, or a couple cap fulls in the intake, or 2:1 replacement of 2 stroke oil in a gas/oil mix.  I’ve done it for nearly 20 years and haven’t ever had an issue.  Trans fluid is super rich in detergents and still lubes well.

Ever really think what Marvel Mystery Oil really is? http://www.marvelmysteryoil.com/

[Sarge 3,463]

I've had a Homelite 2-stroke trimmer now since the early 80's - it has never failed to start and run properly, bet I've only put 2 new spark plugs in it, mostly because I felt bad for the dumb thing and it's refusal to die. I never dump/empty my gas, always use non-ethanol and a quality mix oil. One thing that is religious, never keep the gas more than 4 months for a 2-stroke, and I always add the proper amount of Sta-bil. Same with the newer Stihl blower/vac I bought, always starts on the 2nd pull as the Homelite.

 

One thing before you tear into that tank/filter, ect.

Try running it wide open throttle and adjust the high mix screw - most likely just some gunk got into it. If that doesn't help, using a piece of annealed wire bent into a hook to ****** the filter out through the fill cap and replace/clean it. Be wary of putting new hoses in older machines - hoses aren't sized exactly these days and over time the holes in the tanks get enlarged, which results in some nice leakage, generally all over the operator. The yellow or blue Tygon is best, can be had at any mower shop worth their salt if necessary. Take a chunk of the old lines to make certain on the proper size, bigger is ok but never smaller, of course. If you bevel the ends with a razor blade you can get them forced through the tank holes with needle nosed pliers, some of those new X-jaw ones will reach inside the tank pretty well. That part is a pain in the keister, but once it's done the thing should be good for at least 10yrs. 

 

Sarge

[ebinmaine 67,502]

Just wanted to say thanks for the advice and help on this thread last year.

 

I brought it in to get a compression test and was over 120.

Nice.

 

I asked how much for them to do the carb cleaner and tune... Less than 60 parts included.

AWESOME.

 

I left it there for them to do right... The first time.