IMO your sears mower is 4 stroke. Starter fluid probably has worse effect on the carb. drying out the seals. IMO is why the starting sequence got worse ans worse and they replaced it. Your crank case has oil in it, ever time you pull the rope the piston goes up and down connected to the crankshaft which splashes in the oil and fine film gets drug up onto the cylinder walls and the oil ring (scraper) squeezes off so it not burnt when the engine combusts the gas, otherwise you would have oil burner and have to keep feeding it oil.

Not like two stroke engine were the oil is supended in the gas and the starting fluid actually washes any oil film off the cylinder walls (IMO probably don't hurt nothing due to no heat built up and no load put on the two stroke engine yet). But why take chance just use carb. cleaner (in the spray can) for priming, don't evaporate as quick, has lubrication properties, and probably combusts just as good as starting fluid.

I find that most SGE has routine to get them to start without pulling and pulling (notice I said most!). this maybe pushing the primer buttom certain amount of times (some more some less). Choking then half choking. ect... Most seems to start easily by following the starting procedures in the owners manuals. Some may have small defect which causes the hard starting?????

I feel priming a 4 cycle with gas would be similar to fluid and would do very little harm or damage vs a 2 cycle (that depends on the oil in the gas). Since 1970 I have averaged over 10 yrs per 4 cycle mower on cutting just my 120' X 70' yard. I have probably collected over 30 mowers of the curbs to troubleshoot and donate. I have not found one that was used at a Resident vs a Lawn Cutting Business that was worn-out. This is like 1 hr use per week vs 12 hrs X 5-6 days = at least 60 + hrs a week (then comes the maintenance/care issue).

rcmoser has good points on knowing how the engine likes to be started w/o flooding. If my donated old Briggs (10 approx) d/n start 1st pull it's unusual (dirty or bad plug, bad filter or bad priming 3-5 shots). Look in your carb to know you are getting good shots and 3 are probably recommended vs almost flooding with 5 shots. Good Luck!

Thanks for the opinions. I will try the carb. cleaner as a get-starting spray if necessary. I guess one could put a little gas in a pump spray bottle if necessary -- but maybe the plastic might not like it for the long term. The dollar store does sell a sell a spray bottle made of aluminum.

Why bother when can of carb. cleaner in spray can will last long time and won't go sour. Wally world has their brand pretty cheap. Another side benifit from the carb. cleaner you get little cleaning action also.

Is there a primer bulb circuit's not working? If the bulb's circuit is working, you should see a good shot of fuel into the carb (if the bulb is primed/purged good per pump with the air cleaner off). Attached is a bulb I see dry rotted/cracked on many older mowers. It is very easy to install if you see the ears to compress to release the old rubber/etc.

My mid 70's, early 80's Poulan S-25 chainsaws need purge/primer bulbs to save my arm of 5 pulls vs 2. LOL! Pulling the air filter's cover, and a shot of premix works good (But A Pain with gasket and long screw under the handle). I wonder if a special fuel tank's cap would assist in a purge/prime to ease the starting? If so, where has such a cap been seen or purchased? Thanks in advance! I hope this is not jumping a post vs joining??

The Sear mower with a 10 year old B&S engine I mentioned has no primer bulb.

The thirty year old no-name mower I bought from an older gent for $20 runs fine. But the gas primer bulb does need to be pushed 10 to 15 times to start. Probably the manual (if I had it) would say push the bulb 5 times, but the rubber bulb seems to leak a bit.

replacement primer bulb are usually found at your, sears parts, local hardware store or big box store. Leaking means it cracked and alowing air to enter the system causing the excess pushes to get it to start. It will only get worse. I would just replace it.

Look in the carb to see if the bulb gives you a good shot of fuel in 3-5 pumps. A new bulb s/n be that expensive and worth the repair. If the bulb is bad it�s probably allowing some air affecting performance.

I'll get a replacement bulb from the nearby Mower and Service dealer who has the best selection of parts compared to hardware and big box stores. On the subject of retailers, there is a great small hardware store in between the HD and Lowes. They stay in business because all the employees know a lot (doubt if any are under 65), and they greet you at the door. But instead of being a greeter/security person who only stands at the door; they lead the customer to what they need! What a radical concept.

Recently because of problems, I have been switching back and forth between a five year old Sear mower, and a thirty year no-name mower. Both are B&S engines, 6.75hp for Sears and three something for the no-name mower.

The older mower has a bit more power than the newer more powerful Sears.

Also, the design of the older 3.75 Sprint engine seems better because the new Sear is flat on top and gets way more leaf debris thru the rough screen. The older B&S engine has a fine screen which is also raised. Perhaps B&S 'simplified' things, and in the process made them work a bit less well. Debris is a concern for me since I use my mower(s) as much to shred leaves as to cut grass.

I took home a Scotts mower a neighbor threw out. Just to learn a bit more about carbs. and such. This mower probably was not more than ten or fifteen years old. The plastic by the air filter was 'fixed' by some duct tape. And there were three other problems caused by poor maintence. Sigh. I love the smell of fresh grass cut in the spring. Guess I'm obsolete.

Heck, Robertz! If you are older than 88 years, CHEERS! That's my age, and i repair lawn mowers to keep me out of the funny-farm!
I started at age 70 or so, by fixing lawn mowers i picked up on trash nights. Most needed a carb cleaning, maybe a primer bulb, or some little problem.
No, you aren't obsolete! Just well preserved!