How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Dave Your Own Question
Dave, Handyman
Category: Home Improvement
Satisfied Customers: 3253
Experience:  fix up stuff
Type Your Home Improvement Question Here...
Dave is online now
A new question is answered every 9 seconds

40-1mixture placed in craftsman mower instead of pure gas

Customer Question

My son put a 40-1 gas and oil mixture instead of the pure gas into my 7hp craftsman mower. Even though the gas cans were labeled pure and 40-1. I drained the gas and replaced the plug, but it will start and run for a minute or two and then quit. Is there anything I can do or will I need to take it to sears and pay a minature fortune to have them fix it. Please hurry as we have had a tremendous amount of rain and I am thinking of purchasing a herd of cows to graze. Thanks Steve
Submitted: 11 years ago.
Category: Home Improvement
Expert:  Steve -- a.k.a. Oreport replied 11 years ago.

If the beast (the mower, not your son) has a fuel filter I would
recommend changing it.  If the mower has not yet been used this
season -- you should also check and clean or change any air filter.

If you're unable to resurrect your power mower -- they still
manufacturer great push mowers.  Some hours behind one of those
might give your son sufficient time to reflect on the 'error of his

Besides, I don't think the power mower has yet been manufactured that
can make a lawn look half as good as those old-fashioned push mowers --
don't you agree?

Let me know if you need more input.  If not, thanks for the
opportunity to assist you... I would really appreciate your honoring my
efforts by 'pushing the button' and Accepting this answer.  Adding
a bonus -- should you wish to do so -- is always warmly welcomed.

Good Luck!



Expert:  Glenn Miller replied 11 years ago.
This is not a problem, all you have to do is replace your boy baby. Just kidding. The oil mixture has not damaged the mower. There are two ways to bring the mower back to life. 1: Take the fuel system apart, rince everything with pure gas, reasemble then mow the lawn. Paying special attention to the fuel pump. (usually a diapham between carb and tank or in larger engines where the tank and carb are seperated, a hocky puck sized vacume acuated fuel pump.)Make sure all small holes are clear; use compresssed air at low pressure. 2: Newer mowers have very small jets so that they will run very efficiently and the suface tention of mixed fuel is to great to pass. You will have to dilute oil already in system. So with pure gas in tank continue starting mower letting it run and die untill it purges itself of fuel/oil mixture. Choking it by hand will speed up the proccess. After the engine has burned out mixed fuel in system (Aproximatly 5 min. combined run time). Then you are ready to change plug and mow. I hope you allow the boy baby to help you in this project so that he will learn that following instruction is usually a good thing.
Good Luck, happy mowing,
Expert:  Dave replied 11 years ago.
 You must have dirt/grass in the carb.That mower should run on that mix but smoke a little and eventually foul the plug if a 2 cycle mix is continued to be used several tank fulls.I know this to be fact because at the end of the season I use up my 2 cycle mix in my 4 cycle lawnmower with no ill effects.You may want to check for spark at the plug when it stalls and won't stay running.Your son may have gotten some dirt/grass in the tank but the gas/oil mix is not the problem so don't be too hard on him for that.Don't try running pure gas in a 2 cycle though that won't work.