New to (old) Cubs, just bought my first - a 125!!

[olds45512]

Congrats on the 125. As others have said don't worry about rebuilding the engine until its a necessity, alot of old kohlers smoke a bit but they'll still run forever with no problem. I would change all the fluids and filter, make sure you use a real cub filter and cub hytrans in the rear end, since its summer youll want to run sae30 oil in the engine. I run 89 octanne with 10% ethanal with no problem, I was recommended 89 by a local cub guy to stop back firing when I shut the tractor off annd it works.

[Billy-O]

I have a pair of 125. These are good machines! Good luck with yours!

[PaulS]

Welcome to the narrow frame side. I differ with the gas additive comments. I cannot get ethanol free gas here and do add a product called Startron to my gas and also add a product called Marvel Mystry Oil to the gas and currently am using up some really old Stabil. I have been told that ethanol is definately not a friend to any small engines but especially 2 cycle engines such as chainsaws and outboard motors. From personal experience current gasolines do not remain "fresh" very long. With the current cost of the stuff we can ill afford to dump gallons of the stuff if it is a month or two old. To each his own.

[DoubleO7]

Welcome to the forum!
The problem with running ethanoled gas is:
1. old rubber fuel lines breaking down.
2. the internal surfaces of the diecast and aluminum parts such as the carb do not have the hard anodized surfaces that prevent the water picked up by the ethanol from corroding the diecast and aluminum parts.
The above two happenings on older engines (and new cheapo made Chinese "disposable" yard equipment engines) allows particles to get into parts of the carb that need to always be very clean.

The only time I ever add anything to gasoline is when I am storing for several months over the winter. Read the ingredient labels, for many they are mostly more ethanol or methanol.

[ACecil]

Welcome to OCC! Good luck with your 125.

[Sam Mac]

Originally Posted by DoubleO7

Welcome to the forum!
The problem with running ethanoled gas is:
1. old rubber fuel lines breaking down.
2. the internal surfaces of the diecast and aluminum parts such as the carb do not have the hard anodized surfaces that prevent the water picked up by the ethanol from corroding the diecast and aluminum parts.
The above two happenings on older engines (and new cheapo made Chinese "disposable" yard equipment engines) allows particles to get into parts of the carb that need to always be very clean.

The only time I ever add anything to gasoline is when I am storing for several months over the winter. Read the ingredient labels, for many they are mostly more ethanol or methanol.

Bingo, we have a winner! I won't run ethanol in any of my small engines.

Try this to find ethanol free gas near you http://pure-gas.org/

[Nitro]

Excellent link Sam, found a station on the way to work that I never stop at.

[MinnesotaCadet]

Your 125 is looking great! Good luck with it.

[snoel]

Originally Posted by Sam Mac

Bingo, we have a winner! I won't run ethanol in any of my small engines.

Try this to find ethanol free gas near you http://pure-gas.org/

I checked this out. And found 2. One is the airport, and the other is the marina. Neither is gona' be bargain priced!

[Maxwelhse]

Originally Posted by snoel

I checked this out. And found 2. One is the airport, and the other is the marina. Neither is gona' be bargain priced!

Same problem I had but worse... It's only available at an ag store that has cash only pumps and never seems to have an attendant. I've tried to buy AG diesel for Dad's green tractor there a few times and had no luck at all finding a warm body.

If ethanol is really a big deal the lazy solution is to shut the fuel off and let the carb run dry every time. On my stuff the bowl holds about 1 minute worth of full throttle fuel. I may start doing this every time (as opposed to just shutting the gas off) just because I'm getting paranoid now.

As far as stabilizers and such... if the gas is older than 6 months I drain it and mix it back in with new gas at about 20%... Even my Jeep with O2s and a cat doesn't mind it. I have a habit of filling/draining my generator twice a year and running the gas through vehicles (since the generator is essentially in storage I always run the carb dry). The generator stays full that way and I always have "emergency" mowing gas on hand. I've heard various reports of modern gas spoiling in a few months but I've never personally experienced it. At $4+ a gallon I'm not going to throw it away unless I'm positive its turned to varnish.

The 2 cycle stuff DOES seem more sensitive to elderly/modern fuel. I use my 2 cycle stuff so little that I drain them after every use these days. The oil I buy claims to have stabilizers in it (I run B&S oil in B&S motors and Stihl oil in Stihl motors... it all costs about the same so why not?) but it doesn't seem to make a difference. After about 2 months they never want to start if you leave gas in them.