Using 2 cycle in a 4 cycle. question.

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I work for a Fire Dept. On our fire engines we carry gas cans full of fuel for our generators, chain saws, street saws, and extrication tools. we mix 2 cycle oil at a ratio of 40:1 in all our gas cans and use it in all of our equipment, 2 or 4 cycle.

We do this to keep it simple and to remove the chance of someone pouring unmixed fuel into one of our 2 cycle motors during the heat of the moment which could lead to engine failure on a 2 cycle motor.


Question is... is there any negitive effect on the 4 cycle engine running on fuel mixed 40:1 with 2 cycle oil? And is there any positive effect?
 
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I'd think you are fine, I doubt/hope you don't have to run equipment for too many hours before its replaced.
I have run old 2 stroke mix in my 4 stroke atv without any problems except for the smoke/smell.

What I would do is fill the 4 stroke stuff up at the hall with straight gas but only take the mixed gas on a call if your Fire dept keeps equipment for more than 4 or 5 years. That way the 4 strokes do see straight gas most of the time.

If my wife used my small engines more I might use the same policy! Mixed gas only in the shed...
Ian
 
Other than your 4-cycle engines may ended up burning richer (if you can adjust the mixture screw in the carb you'll be able to compensate for it), the answer is no harm done.

Q.
 
My vote is no 40:1 in a 4-cycle engine. It will no doubt eventually over time form a lot more carbon in the combustion chamber and reduce the service life of the 4 cycle engine.

The plug may foul when you need the engine the most as well.

If you really insisted on doing it I would use a hotter plug. (might be in the grey area as well in a fire dept)

If you had a situation arise where the 4-cycle engine (fueled with 2-cycle gas) did not work and a life were lost... the lawyers... would tear you apart on this issue in court no matter what the fault was. Can't do this when you serve the public... it's against procedure/ manufacturer's specs. Period.

What you do with your own stuff is your business....what you do on the business of a fire dept run by the City is their call.

They have to pay the multi-million dollar verdicts against the city. Not woth loosing your job as well over either.

Stick to the rule book...this is at best a grey area. Enough to get a "beyond a reasonable doubt" jury that does not read BITOG.



My .02
 
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There is absolutely nothing wrong with doing this. In fact, I've been recommending this very thing to our customers for the past 20 years, many of whom have teenagers or hired help that frequently get things mixed up. Many of our contractor customers do the same thing because it's sometimes easy to grab the wrong can of fuel, and we see zero negative side effects to this practice.

I would recommend that you get some Stihl 2-cycle oil and mix it at 50:1 ratio, the ratio that it's designed for.

You won't need a hotter plug, but you may have to change it more often.

I can't speak about the liability issue, because it has never come up. I'll just say that I think there are way too many lawyers in this country, and leave it at that.
 
I just received a response from a trial attorney I know.


Plain and simple he says not to do anything "creative" that's not in the "Book".

Write up a proposal if you want to make a change. It's how the system works. Then it has to be reviewed and put into operating procedure across the board.

This change would have to be tested...engines torn apart and compared etc to make it legal proof.

He said this "minor change" would cost a department thousands in testing alone and not to haul off and do it.

No engine manufacturer would support you in court. It's like running diesel instead of gasoline in the minds of a jury who were well prepared by a good attorney.

The Fire Chief has to sign off on every little thing and 3rd party testing is a mandate for things like this.

Briggs explicitely says to use " fresh 87 octane gasoline ".

They would need a letter on fine from Briggs saying it's ok to use "40:1 gasoline mix with a specific 2-cycle oil plus oil in the sump".

Nobody would stick their necks out on this one.
 
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Originally Posted By: hate2work

There is absolutely nothing wrong with doing this. In fact, I've been recommending this very thing to our customers for the past 20 years, many of whom have teenagers or hired help that frequently get things mixed up. Many of our contractor customers do the same thing because it's sometimes easy to grab the wrong can of fuel, and we see zero negative side effects to this practice.

I would recommend that you get some Stihl 2-cycle oil and mix it at 50:1 ratio, the ratio that it's designed for.

You won't need a hotter plug, but you may have to change it more often.

I can't speak about the liability issue, because it has never come up. I'll just say that I think there are way too many lawyers in this country, and leave it at that.


Hey, don't be a hater.......Actually, I am lawyer and agree with everything you said....even the last part. The only thing I have had a hard time with the Stihl Ultra 50:1 was in my lawn boy.

As for liability, Pete ease up. Your friend surely must have heard of Soveriegn Immunity. While not invincible,it requires gross negligence(reckless, willful or wanton conduct) to pierce. Your best guess as to what type of fuel to use does not qualify reckless. Immunity protects our safety service providers. However, If a fire department was to make a reckless decision it would be to buy a Poulan saw, it would never get started and the victim would be trapped under the tree forever.....
happy2.gif


As for product warranties, buy the damm stuff and run it. ^%$#@ testing it.
 
To the OP (upallnight) Laws vary by jurisdiction. There are statutes and case law to protect civil servants....but Juries and Judges are unpredictable. Can you check to see if there are any state standards for power tool/small engine use by emergency departments, check to see how other departments handle it, find out if there is an accepted norm. You can check with your city, county or township counsel and explain what your situation is, and what research you have done.

I am not sure how much to trust legal or oil advice on the internet. It is always better to look into things and get an opinion. Good luck to you, and thank you for your service.
 
Anyways, I understand this. Of course it is important to reduce the number of alternative fuels to avoid fumble and also minimize logistic problems. Look at the armed forces, they really try to reduce number of fuel types to use.
But just pouring 2T oil in all gas may be over simplistic. Maybe you could aim for replacing the 2T equipment with 4T equipment? Should be possible by now.
Maybe make sure that you could also use the same engine oil in all engines including the fire trucks? HDEO?
Also finding one manufacturer for all stuff too, just to make controls and handling similar for the staff.
 
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Originally Posted By: Quest
Other than your 4-cycle engines may ended up burning richer (if you can adjust the mixture screw in the carb you'll be able to compensate for it), the answer is no harm done.

Q.


Actually it will run leaner. Well known in the 2 stroke dirt bike world, more oil= leaner due to less gas in the volume.
 
I've used 2-cycle fuel mixed at 40:1 in my JD lawn tractor several times, to keep from having to go buy more gas when I'm out. I can't tell any difference in the way my JD starts, runs, etc. It doesn't seem to after-fire as much when I shut it off when using the mixed 2-cycle fuel.
 
Even if its a 2 cycle (water cooled) tcw-3 ashless oil? I thought ash was part of the problem, that would cause deposits that you speak about? I have been using ashless (specified) Walmart tcw-3 in the blue gallon jug for sometime now, and have yet to see carbon deposits on my plugs, in my exhaust ports/system etc. No smells, smoke, or carbon. Now you may have an arguement, say if the product is of a non-ashless type, such is the case with most 2 cycle air cooled oils. But marine based tcw-3 ashless rated oils are altogether different. Every now and then I would add a bottle of Chevron fuel system cleaner to my tanks. But 2 cycle tcw-3 ashless marine oil gets added to my tanks everytime (Shell V-Power). What say you?

Best Regards
 
i put 3 gallons of 40:1 gas in to the car-2000 neon. nothing happened, and ran fine.. The tank was near empty on the car also..
 
Interesting take on the legal issues.

Would intentionally adding two stroke oil to 4 stroke fuel be defensible by trying to prevent the negligent omission of two stroke oil on a piece of mission critical equipment ?

I know if I was trapped in a burning car which choice I'd rather the OP make.
 
I don't think that 40:1 two cycle fuel being burned in an air cooled engine will care whether it is in a 4-cycle or a 2-cycle engine.

The oil is designed to be burned.

I use a 40:1 mix in all of my lawn care fuel too - simplifies the fuel supply - never had an issue with it - and it seems to extend the life of the stored fuel.
 
Briggs said that they on occasion get a machine in for service (with a tech's call) about a dye in the gasoline and it shows positive for oil in the gas. Warranty is void.

Why? They find it to cause "wet fouling" of the combustion chamber and then coking. Especially in commercial units run hot and long. It increases the possibility of throwing a rod.

..FYI
 
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