E10 and old 2-stroke engines?

p10

Cadet
Joined
Jul 31, 2011
Messages
17
Norway introduced E10 fuel this spring, as a replacement for the E5 we have had for a while. And there's a lot of talk about how harmful this E10 fuel will be for older engines, and especially 2-stroke outboard engines. But there's little facts and experience on this over here, so I was wondering what your experience is?

The sticky in this forum already explained the myth about E10 and water, but there's also a lot of concern that E10 will destroy fuel lines, gaskets and other rubber parts in the fuel system. Is this true?

Are there any measures needed to be taken to be able to run a 2-stroke engine on E10? I have a 3 cyl mid 80ies 30hp Yamaha and a 2 cyl late 90ies 30hp Evinrude.
 
Last edited:

racerone

Supreme Mariner
Joined
Dec 28, 2013
Messages
36,274
What colour is the float bowl gasket on the 30 Evinrude ?----Black or brown?----If brown , it will stand up to modern fuel.----Just run carburetors dry when motor is not in use.
 

garbageguy

Lieutenant Commander
Joined
May 8, 2012
Messages
1,532
I've heard of gummed-up fuel lines, etc on older 2 and 4 stroke engines. I have not seen that, and on a few old 2 strokes we have, we run the E10 fuel and drain fuel system in off-season after running some fuel stabilizer through it, have not had a problem with the fuel yet (but we keep a close eye, and don't need to go far off-shore)
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
Staff member
Joined
Jul 23, 2011
Messages
47,499
Make sure the fuel lines have been manufactured in the last 25 years to be ethanol friendly
 

racerone

Supreme Mariner
Joined
Dec 28, 2013
Messages
36,274
Picked up an older chainsaw as part of a deal.----No spark.-----Found an ignition module and the thing started and ran very well.-----The next day it sputtered but would not run.-----Found that the gas line from inside the tank to carburetor was " melted " from modern fuel ?-----Replaced that line with something I had.----Started and ran fine again.
 

dingbat

Supreme Mariner
Joined
Nov 20, 2001
Messages
15,484
Found that the gas line from inside the tank to carburetor was " melted " from modern fuel ?
Bought a Stihl 028 to clear a lot in 1989. Same thing happened to the plastic “aquarium tubing” in the tank @ 2015 or so. Replaced with Tygon tubing.

Watching, but still no problem with the same line on my shindiawa trimmer of the same vintage
 

airshot

Rear Admiral
Joined
Jul 22, 2008
Messages
4,318
Been using E 10 since it came out, there were many warnings about having alchol compliant hoses and gaskets and give old fuel systems a thorough cleaning before switching to E10 fuels. If those warningS were followed you wont have any issues !! My neighbor has numerous old cars from the 60-70's and I helped him convert his hoses etc to alcohol freindly ones. Did the same on my old engines, not one single issue in all these years !!
 

p10

Cadet
Joined
Jul 31, 2011
Messages
17
Been using E 10 since it came out, there were many warnings about having alchol compliant hoses and gaskets and give old fuel systems a thorough cleaning before switching to E10 fuels. If those warningS were followed you wont have any issues !! My neighbor has numerous old cars from the 60-70's and I helped him convert his hoses etc to alcohol freindly ones. Did the same on my old engines, not one single issue in all these years !!
So, swapping out hoses and gaskets is recommended? Are there any other components I would want to swap for newer ones?
 

909

Chief Petty Officer
Joined
Jul 19, 2021
Messages
537
Guess it depends on your definition of "older" engines.

Never had an issue with E10
 

dingbat

Supreme Mariner
Joined
Nov 20, 2001
Messages
15,484
So, swapping out hoses and gaskets is recommended?
Swap out any fuel lines that are 10 years or older.

Buna gaskets (black) make it 4-5 years before they start to weep with E10. Wouldn't change gaskets until they start to weep or the carbs need rebuilt
 

p10

Cadet
Joined
Jul 31, 2011
Messages
17
If your outboard was manufactured in the 90's, you should have no problems running E10
One is a late 90ies 2cyl 30hp Evinrude. The other is a mid 80ies 3cyl 30hp Yamaha. Both are 2 stroke.
 

mike_i

Master Chief Petty Officer
Joined
Jun 28, 2017
Messages
881
I've read a lot of posts regarding problems with fiberglass fuel tanks and E15. Do you know the age and material of your fuel tank?
 

airshot

Rear Admiral
Joined
Jul 22, 2008
Messages
4,318
I've read a lot of posts regarding problems with fiberglass fuel tanks and E15. Do you know the age and material of your fuel tank?
I would never use a fiberglass fuel tank on anything, fiberglass is way to unstable when in contact with other chemicals. Plastic would be a far safer choice in my opinion...
 

airshot

Rear Admiral
Joined
Jul 22, 2008
Messages
4,318
One is a late 90ies 2cyl 30hp Evinrude. The other is a mid 80ies 3cyl 30hp Yamaha. Both are 2 stroke.
The 90's model will already be set up for E10 fuels, the eighties models should have fuel hoses changed over, but in reality, they should have been changed years back because fuel lines are only good for about ten years. So if the hoses were changed at that interval they would/ should be E10 rated already....all motors should have an inline filter close to the motor to keep debris out of the motor, if they don't I add one !!
 

p10

Cadet
Joined
Jul 31, 2011
Messages
17
I've read a lot of posts regarding problems with fiberglass fuel tanks and E15. Do you know the age and material of your fuel tank?
The fuel tanks are brand new plastic ones, that I believe were rated safe for E10 iirc.
 
Top