lead additive, or not?

zippy1 · #1 10-31-2010, 09:16 PM

Now that my 125 is up and running good, would you all recommend using a lead additive? My other tractors are in their eighties so it's never crossed my mind. Then thinking today, maybe I should, being it's a sixties tractor.
What do you think?
I thought with automobiles, one would have the valves and seats done?
Here on the farm I just take gas from the tank, (octane ?) or would getting a higher octane in town be better?
Confused???

Matt G. · #2 10-31-2010, 09:25 PM

Just use regular 87 octane and MMO...forget the lead additive. It should do about the same thing for less cost. My dad puts lead additive in the gas for his Farmall, but that's a MUCH older engine with more primitive valve and valve seat materials.

JaysNJcub127 · #3 10-31-2010, 10:10 PM

Not sure what the gas is by you Matt, but here in NJ, there are lots of additives and over 10% ethonal so 93 octane it is for small engines here !!!! The repair shops also tell you to use the high test or they will not warranty the new products !!!

Matt G. · #4 10-31-2010, 10:38 PM

Our gas has at least 10% ethanol, too, and I've never had a problem. It's been said here many times before: you're wasting your money putting high-test in an old Kohler. You don't need it with the really low compression ratios these engines have.

zippy1 · #5 10-31-2010, 11:05 PM

I trust you Matt. If you say it, it is! I just wasn't sure about the whole thing, I've heard one thing years ago, and then another, and with the mind I've got

I know I could easely get things mixed up one way or another.
So thanks.

JaysNJcub127 · #6 11-01-2010, 05:45 AM

Quote:

Originally Posted by Matt G.

Our gas has at least 10% ethanol, too, and I've never had a problem. It's been said here many times before: you're wasting your money putting high-test in an old Kohler. You don't need it with the really low compression ratios these engines have.

I hear you matt, my stuff all runs fine on the 87, but the 93 breaks down much faster and gels up up faster than the 87. Thats the reason I use it.

Sam Mac · #7 11-01-2010, 06:02 AM

As Matt said you do not need anything more than 87 but the crap they call gas goes bad so fast I'm running VP SEF 94 or 112 race gas when I have some leftover from my racecar. Yes it's expensive but it keeps the carb nice and clean. I also use SeaFoam in all my small engines.
http://www.vpracingfuels.com/sef-94.html

ol'George · #8 11-01-2010, 09:21 AM

Some things to think about:
A lot more regular gas gets sold @ a filling station than premium.
That usually insures it is fresher than premium that might be sitting in the underground tank a much longer time.
Many studies show that more octane than is needed, although will do no harm, is just wasting money.
Nearly all small engines, are very low compression and can use non premium gas just fine.
It's your choice, but for my 55 years experience, this has been true.
Now if an engine had been modified with much higher compression, then a higher octane is beneficial and is required so as to prevent pre ignition and/or "knock" which is damaging.
As far as tetraethyl lead added to the old gas, it was for valve lube, & it also increases octane.
If an engine has a hardened valve seat insert, there is no need for lead in todays fuel.

bsty44 · #9 11-04-2010, 07:39 PM

Here in the Daytona area , we can get non-ethanol gas at a couple of
propane places. I've just gotten an 1811 , and it will only get very occasional use, so I intend to use the non-eth, and a fuel cut-off so the carb can be run dry, in order to reduce fuel degradation during non use times.
Should an additive be used in this engine for valve seat wear prevention?
Since it was made at a time well into the non leaded era , wouldn't it have hardened seats ?
Thanks for any answers .

Merk · #10 11-04-2010, 08:27 PM

Page 5 of this Kohler manual has the answer to the question of adding a lead additive:
http://www.kohlerengines.com/onlinec...1346_c_all.pdf
It aslo talks about using ethanol in your fuel.

You can use a lead additive. It is a waste of good money and can lead to more deposits in the cumbustion chamber.

The Cub Cadet manual says to use leaded fuel. One thing to remember the manual was printed when the Cub was made. The Kohler manual on their web site is up to date.

Most Kohler engines are lucky to have a compression ratio of 7/7.5 to 1. You can run a compression ratio of 9 to 1 on 87 octane gas with no problems. There is no need to run the higher octane gas in your Kohler motor. There are times the higher octane gas with hurt performace rather than help it.

Best thing you can do is to go to a 30 day gas rule and add a good fuel stablizer to your fuel. Two good fuel stablizers are the one made by Briggs and Stratton and Sta-Bil. Storing your fuel in a sealed fuel container is a must to good storage.