Non-ethanol 87 mixed with 100LL to raise octane

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Brief history....I have a restored JD 212 with the K301 Kohler that I also rebuilt about 1 1/2 years ago. I have been using non-ethanol 87 from a frequently used pump and have had the timing set at 14 deg BTDC.

I wanted to use a more retarded timing than the spec'd 20 deg adv for a good while until I had about 100 hours on the motor. Not that this is normal practice, but since it had adequate power I just left it alone. So I have it set now at 18-19 deg adv and I would like opinions on using higher octane fuel to reduce the chance of possible detonation when it's working hard. Another factor would be the added lead content for the valves. I had them ground, but still retain the original seats.

Perhaps the higher octane is not needed, but if so, would mixing some 100LL with the non-ethanol 87 be a good idea? I would also use the mixed fuel for other equipment like my KM-110 trimmer and a couple Husky saws.

I really don't want any of the 89 or 93 from the gas stations....no telling how long that 93 sits in the tanks, and to make 89, 93 is generally mixed with the 87 at the pump....and it's an ethanol blend.
 
The K301 is going to be a terribly durable engine. Running E-free in it is a good idea, but it does not need particularly high octane. The E-free regular should be more than adequate with factory timing.
 
100LL is not really low lead, very bad idea compared to just using 87 octane e0

You would risk lead buildup and lead fouling of the spark plugs etc.
 
IIRC from my Blendineer days 100LL has 2 or slightly above 2 g/gal max lead content, vs. old school leaded pump gasoline and NASCAR /TORCO furls having 4 g/gal max lead content. That was a number of years ago but doubtful it's changed much if at all.

Seasonal volatility requrements for pump gas makes for decent turnover in my experience. However pump sales volumes, and thus terminal order volumes for station delivery, tend to be lower in less affluent areas for higher octane products.
 
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If you replaced all fuel lines during the re-build, just use mid-grade.
E-10 won't harm the valve seats, that generally shows up at higher RPMs, and
this is likely governed to 3300-3600 RPM.
 
A little lead goes a VERY long way.(for valve recession)

100LL mixed 1:20 (or even 1:30) with unleaded will give you what the pumps were selling in the very early 90's.

The Kohler engine is relatively low compression - you should be able to bump the timing up to 24 on 87-E0 and not get any detonation.
 
Originally Posted By: dwendt44
If you replaced all fuel lines during the re-build, just use mid-grade.
E-10 won't harm the valve seats, that generally shows up at higher RPMs, and
this is likely governed to 3300-3600 RPM.


Yes, all lines were replaced and it's governed @ 3600. But I will try at all costs to avoid "E"vil 10 pump gas in my small engines unless I know I'm going to consume it within a week....or that weekend...
wink.gif
 
Originally Posted By: i6pwr
Originally Posted By: dwendt44
If you replaced all fuel lines during the re-build, just use mid-grade.
E-10 won't harm the valve seats, that generally shows up at higher RPMs, and
this is likely governed to 3300-3600 RPM.


Yes, all lines were replaced and it's governed @ 3600. But I will try at all costs to avoid "E"vil 10 pump gas in my small engines unless I know I'm going to consume it within a week....or that weekend...
wink.gif



Evil E10? Whatever. That's all I have ran for years. No stabilizers, no magic potions, no yearly or weekly carb repairs, no replacing fuel lines every other year or any of the other bologna I read about here. I just add it to the tank and mow. I even let it set in the tank over the winter and it still, by some miracle, starts in the spring.

You have a robust old piece of equipment with low compression- you could get the town drunk to take a leak in the tank after a good bender and it'd probably still run fine. Set the timing to spec and enjoy life.
 
Originally Posted By: The_Eric
you could get the town drunk to take a leak in the tank after a good bender and it'd probably still run fine. Set the timing to spec and enjoy life.


Ha...you're prob right...lol.

I agree E 10 isn't always bad, my FH430V starts all the time on it, the trimmers tend to stumble if it sits for a month or so. The JD JX-75 push mower hates it and I need to drain the float often. The Kohler will pop at idle sometimes if the E 10 sits for awhile, but E0 runs perfect in everything even siting over the winter, the Kohler pops to life immediately if the E0 has been in the tank for 3 months.
 
My '74 Economy Jim Dandy with a K321 ran fine on any of the fuels I put in it, but my '61 Power King with a Briggs 23 despises ethanol. I've never been through the carb. on it so maybe a kit with improved materials would help its tolerance for ethanol, but I've had E-free available every place I've lived since owning it so it gets it whenever possible. But during the times your machine is frequently used I'd go for higher octane with ethanol over E-free regular.
 
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Originally Posted By: Marco620
0 ethanol has 3rd more energy per BTU. Great choice.


No it doesnt. That makes no sense.. more energy per btu?

now if you meant more btu per gallon.. you would still be wrong..

because with 10% ethanol mix its more like 3-5%

Straight gas "e0" is about 114k-115k btu/gal

10% ethanol gas is around 110k-111k btu/gal
 
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