Mine seems to prefer premium fuel.

[John Joseph McVeigh]

I've been using 105/110 octain racing gas for 20+yrs. for all my 2cycle equipment .
Has no ethanol and has a preservative in it. 2gals @ 8.00 a gal is way cheaper than
the quart cans sold in stores in the last couple years and it will normally last me
A year.

Does the racing fuel comes with a preservative already in it, or do you add one yourself? If the latter, which preservative do you use?

 

[buickanddeere]

There is no difference in carbon deposites. In the bad old days of leaded gasoline .premium would leave more lead behind than regular .

 

[HC54]

The fuel already has the preservative in it.

 

[prs]

I have an update. Kubota gas engine. I have switched back to regular grade with "up to 10% alcohol" and notice NO difference now. BUT (yes, that is a big but) I had a problem with the engine of which I was unaware and with such problem the premium fuel may have helped. I thought I was losing peak power and RPMs were dropping more and more under the same loads while mowing up grade and the exhaust gasses were getting really hot during such upgrade runs. This got worse over about 10 gallons of the premium fuel.

After a day's work I was idling to cool down before clean-up and parking. I noticed a miss. I put my spark tester on high tension cable #1 and sure enough it would miss now and then, but the engine was missing even when that cylinder did not. So, I tested #2 and #3; both of which would miss on occasion; making the overall miss pattern very noticeable. I am thinking carburetor problem, maybe; or pulse generator. The carb settings are tamper proof. I intended to check the carb's bowl after it cooled, but access is difficult so when it was cool I first checked the spark plugs. OH MY!!!!! Maybe I reported this a few weeks ago, I forget.

Evidently this machine was washed or left out in rain with hood up at dealership and water flooded the spark plug recesses. The plugs were so corroded that it is a wonder the 6 point plug socket got them out. The corrosion went right down into the plug core of all three, its a wonder it ran at all! So I cleaned the ports and replaced the damaged plugs. Ran/runs better than ever, no missing, way less RPM drop on up slopes under mower load. Continued with premium fuel until next time to go get 30 gallons, at which time I got the up to 20 proof regular (10% alcohol or less). No difference I can detect at all now that I have used almost all of that 30 gallons. I still use premium fuel for two-stroke at 50:1, but with no difference in performance will use regular grade in the Ventrac's Kubota gasser.

prs

 

[John Joseph McVeigh]

I would raise **** with the dealer!

 

[prs]

I "informed" the dealer. His response was that such rust is normal with tractors that sit outside on the lot at dealership and at manufacturer's lot. That may be so, but with the hood up? Or, can strong storms blow rain up in under the hood? Or during transport in heavy rain, can water blow in to flood the plug ports which are just a little off of vertical in this engine? Or did some employee power wash the machine in prep?

Since I park in an out building and DO NOT water wash around the engine, but rather use a blower; the problem should not recur.

prs

 

[John Joseph McVeigh]

I "informed" the dealer. His response was that such rust is normal with tractors that sit outside on the lot at dealership and at manufacturer's lot. That may be so, but with the hood up? Or, can strong storms blow rain up in under the hood? Or during transport in heavy rain, can water blow in to flood the plug ports which are just a little off of vertical in this engine? Or did some employee power wash the machine in prep?

Since I park in an out building and DO NOT water wash around the engine, but rather use a blower; the problem should not recur.

prs

The dealer needs an attitude adjustment. Considering the cost of these machines, the least that the dealer could do is to lower the hood and to put a tarp over the entire tractor!