Ethanol Gas Observations

RBoyd1971

Petty Officer 2nd Class
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Oct 20, 2020
Messages
165
Decided to run 87 Octane E10 in my 1983 Johnson 90 hp V4. First thing that happened was a couple of days later, an old plug made of JB weld in the bottom of my tank softened up and 15 gallons drained to the ground. Yea that hurt, ha ha. Anyhow, after running a few hours, I pulled the plugs and checked things out. The plugs were completely clean. Not grayish like overly lean but almost like new looking. Never experience this before. Usually they are a golden brown with a little carbon. They even had some greenish residue on the grounding strap that I hadn't seen before. I scoped the cylinders and they were completely clean except for a generous amount of 2 stroke oil. Looked like I had decarbonized it. I checked compression and one cylinder was 150 psi and the other three were in the 140s. The second highest was cylinder number 3 at 148 which has a scored piston on the bypass side. Using a Mac tools gage. Anyone else ever experienced this. I finally got rid of the hesitation this motor has always had at mid-range and it runs pretty much perfect now even though it was used and abused by a commercial fisherman in the gulf of Mexico for quite a few years, ha ha. Now with that said, I poured some love into this thing over the past year. I like polishing turds if you know what I mean.
 

saltchuckmatt

Commander
Joined
Jul 19, 2019
Messages
2,646
Decided to run 87 Octane E10 in my 1983 Johnson 90 hp V4. First thing that happened was a couple of days later, an old plug made of JB weld in the bottom of my tank softened up and 15 gallons drained to the ground. Yea that hurt, ha ha. Anyhow, after running a few hours, I pulled the plugs and checked things out. The plugs were completely clean. Not grayish like overly lean but almost like new looking. Never experience this before. Usually they are a golden brown with a little carbon. They even had some greenish residue on the grounding strap that I hadn't seen before. I scoped the cylinders and they were completely clean except for a generous amount of 2 stroke oil. Looked like I had decarbonized it. I checked compression and one cylinder was 150 psi and the other three were in the 140s. The second highest was cylinder number 3 at 148 which has a scored piston on the bypass side. Using a Mac tools gage. Anyone else ever experienced this. I finally got rid of the hesitation this motor has always had at mid-range and it runs pretty much perfect now even though it was used and abused by a commercial fisherman in the gulf of Mexico for quite a few years, ha ha. Now with that said, I poured some love into this thing over the past year. I like polishing turds if you know what I mean.
Well the comments should be interesting on this one.
 

saltchuckmatt

Commander
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Jul 19, 2019
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2,646
Yes, and 15 gallons of gas went where??? Sh**, in my state that would be a superfund site!
 

Chris1956

Supreme Mariner
Joined
Mar 25, 2004
Messages
27,852
Fiberglass tanks are not used with ethanol, because the alcohol is hard on FG. You see that in the JB weld failure.

A green tinge on spark plugs is an indication of overheat. Same thing with the real clean spark plugs. Your carbs may be partially clogged leading to lean mixture. alcohol often loosens debris in the fuel system. This debris can clog stuff.

You should see dark brown to light brown deposits on spark plugs as one would expect.
 

RBoyd1971

Petty Officer 2nd Class
Joined
Oct 20, 2020
Messages
165
Not overheating. I shot it with an IR thermometer and it was running 138. If carbs are plugged, they are equally plugged because all 4 plugs were identical. I don't think that's the case though cause it ran flawless. Checked the timing as well and it was spot on. I think it all is a result of the ethanol. You wouldn't think that being it's E10, but seems to be the case. Heck, I was wondering about the head gaskets but the compression kinda rules that out.
 

RBoyd1971

Petty Officer 2nd Class
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Oct 20, 2020
Messages
165
Yes, and 15 gallons of gas went where??? Sh**, in my state that would be a superfund site!
Well I'm actually an environmental scientist and no that does not meet the criteria for becoming a superfund site, ha ha. The fuel is gone but the oil lingers. Bacteria will make a meal of it soon enough.
 

dingbat

Supreme Mariner
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Nov 20, 2001
Messages
16,081
I think it all is a result of the ethanol. You wouldn't think that being it's E10, but seems to be the case. Heck, I was wondering about the head gaskets but the compression kinda rules that out.
Been running E10 in my 1997 200 Evinrude for 20+ years.

Changed out the original carb gaskets to the newer brown version and never looked back.

E10 has no affect on spark plugs. Still the nice, light brown color they always are when running right.

The only time I had “clean” plugs was the time a head gasket was compromised, allowing cooling water to enter the combustion chamber, steam cleaning the plugs in the process.

Motor ran well. Compression was good. The give away was the “steam cleaned” plugs on the compromised head gasket
 

oldboat1

Fleet Admiral
Joined
Apr 3, 2002
Messages
9,612
^^
like runnin' in the rain --

It done got cloudy and started to rain
I tooted my horn for the passin' lane
The rain water blowin' all under my hood
I know that I was doin' my motor good
 

saltchuckmatt

Commander
Joined
Jul 19, 2019
Messages
2,646
Well I'm actually an environmental scientist and no that does not meet the criteria for becoming a superfund site, ha ha. The fuel is gone but the oil lingers. Bacteria will make a meal of it soon enough.
Bio remediation.....not quite sure bacteria is keeping up with humankind.
 

RBoyd1971

Petty Officer 2nd Class
Joined
Oct 20, 2020
Messages
165
Leaking fuel tank in a boat?? An accident waiting to happen !!!
Well, to be fair, it wasn't leaking when I was running it or when I parked it. That only happened after it sat a few days. I would never allow fuel to be leaking anywhere anytime, ha ha.
 

RBoyd1971

Petty Officer 2nd Class
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Oct 20, 2020
Messages
165
Probably leaked into the bilge and then out the plug hole to the ground like he said.
Yea, it's final resting place was at the rear of the boat on the ground. There no smell of gas there now. Been in the upper 90s here and it was in the bright sun. Oddly enough you can't really tell there is or was about 40 ounces of oil there. No streams or anything around.
 

saltchuckmatt

Commander
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Jul 19, 2019
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2,646
Yea, it's final resting place was at the rear of the boat on the ground. There no smell of gas there now. Been in the upper 90s here and it was in the bright sun. Oddly enough you can't really tell there is or was about 40 ounces of oil there. No streams or anything around.
Leaking fuel in a boat is certainly a potential dangerous situation.... environmentally has it's repercussions as well. Luckily nothing happened but it's a good lesson learned for everyone out there. Stay safe.
 

RBoyd1971

Petty Officer 2nd Class
Joined
Oct 20, 2020
Messages
165
Yea, I'm grateful it didn't start pouring out while underway. Also, you never know what type of sketch repairs someone made on something before you got it. I'll be looking for JB weld on any tanks I get in the future.
 
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