Lawn mower repair for frustration and loss

[Xist]

The pull string?

I had not heard of that. Opinion seems pretty evenly split between this idea being genius and reckless and idiotic.

[redpoint5]

Reel mowers aren't worth the hassle. They don't do a good job cutting, don't mulch, and take too long. That said, you can often find them free, and they are satisfying to use the first time.

I'm considering artificial turf for the front lawn since it's so small and useless for recreation.

I've never used a corded electric, but I could see these being ok for small lawns. Battery makes no sense to me considering the initial cost and cost for replacement batteries.

I bought the cheapest push mower I could find 10 years ago, do nothing to maintain it, store it outside in the rain, and it always starts with fresh fuel. I'll top off the oil maybe once per year, or when I forget and it runs out, momentarily seizing the engine. It always runs again after adding oil.

[freebeard]

I had not heard of that. Opinion seems pretty evenly split between this idea being genius and reckless and idiotic.

Well, I hadn't mentioned it to many others.

What could possibly go wrong? Look for a one-way coupler, like were used on hand-crank (e.g., Model T) engines.

[Frank Lee]

AFAIK it isn't the issue. "If it ain't broke, don't fix it"

[Stubby79]

These things are terribly slow to rev up...a couple of seconds to get up to speed. Yoinking out the drill/starter/doohickey before it gets going probably isn't difficult.

Then again, it came with a one-way clutch that was engaged by the pull starter...attaching that to the drill would make more sense.

[Xist]

Originally Posted by redpoint5

Reel mowers aren't worth the hassle. They don't do a good job cutting, don't mulch, and take too long. That said, you can often find them free, and they are satisfying to use the first time.

I slowly drive a car with a manual transmission and manual steering.

I do many things the hard way.

The rougher right end of this blade of grass was cut by a gas-powered rotary mower, whereas the smoother left end was cut by a reel mower.

Curses! I thought I had taken enough precautions to make sure I did not lose what I was writing, but somehow I posted partway through, and thus lost the rest of what I wrote!

Now with no sources!

Pushing a reel mower uses 153 calories in twenty minutes. Gas mowers only use 115. How do reel mowers only use 38 calories and 33% more? How many calories does the gas mower itself burn? Gas contains 31,500 calories per gallon and while there are too many variables in play, many people say they use about a gallon an hour. Therefore 10,500 calories in twenty minutes, and I would be 276x as efficient!

Someone commented the day before he left for college his dad bought a riding mower and said "Teenage boys turn free room and board into cut grass." Somebody else wrote that if you are concerned about the fuel economy of your lawn mower you area not ready for home ownership.

Kids say the darnndest things!

Toolgirl borrowed three mowers and found that a normal push mower used 1.7 gallons and 3 hours to mow her lawn of unspecified size, the 36" riding mower took 1.8 gallons and 1.5 hours, and the 54" rider took 1.9 gallons and 30 minutes.

I forget what else I posted. You guys got off easy!

[cajunfj40]

Hello Xist,

What make and model of mower? Sometimes looking at an exploded parts diagram can be a real help for this sort of troubleshooting.

Do you know if it has a blade-brake? A problem with the linkage for one can cause issues, especially if it is tied into an electrical shutoff, like a safety circuit that grounds the ignition primary. If the blade brake came half-on somehow, it could have smoked itself (would smell like burning brakes/clutch) and failed. If engine still turns over, though, more likely to be ignition safety circuit than brake. Unless this is a fancy mower that will shut off the blade without shutting off the engine.

What was the mower doing/not doing before you replaced the air filter, oil, gasoline, gasoline filter (does it have one?), and spark plug, plus cleaned the carburetor?

How did you clean the carburetor? Did you replace any gaskets?

You said it was smoking before it quit - what color smoke? Did it sound like it was laboring hard or did it just cut off like it ran out of gas?

When was the last time the blade was sharpened and/or balanced? Dull blades load the mower down bad. Unbalanced blades make it shake. I've sharpened them with an angle-grinder while holding the blade between a 2x4 and a concrete step. Just make 'em look sharp and relatively even, if you don't want to take the blade in for "proper" sharpening.

Ever hit any nasty rocks/roots with it? Depending on where the key is (if it has one), the flywheel could be misaligned due to a busted/sheared key and thus be putting the timing off some. If it ran OK before, though, this is unlikely.

How dirty are the cooling fins/fan? Might be time to pull off any fairings/shrouds/etc. and blow out all the dried grass/sticks/etc. If it overheats, it can quit for a variety of reasons.

When you get back to it, check the oil and gas first to make sure it didn't run out of either. Sometimes it is the simple things - especially if the machine has one pissed off.

For a no-start condition, Gasoline Fumes has the right idea:

You need:
compression
spark
fuel
air

Which one is missing?

You can check for (some, anyway) compression by pulling the spark plug out, grounding the wire, and pulling the engine over - you should get puffing out the spark plug hole that is difficult to seal in with your finger over the hole. You can also use a compression tester if it doesn't stick in too far. If compression seems really low, put a teaspoon/tablespoon of oil in the spark plug hole, pull it over a few times, and retest. If compression gets way better, the rings are worn. If not, there's sometimes a compression release so you won't always get good results on a good engine. Could be worn valves. Could also be a bad head gasket. All three of those don't usually "go bad" between one mowing session and the next, though. If the mower was severely overheated when it last quit, those become more likely, unfortunately. Mowers'll run on pretty low compression, though, just be down on power.

This is a good time to look at the spark plug, see if it is wet with gas, or oily, or covered in soot, or broken, or burned-up looking, etc. Plenty of charts online to compare it to. Also check that the gap is correct.

Spark is next - connect the plug wire to the plug and rig it so the threads/metal part of the plug body is touching the cylinder head. Pull the engine over and watch/listen for spark. Note: with the plug out you will get gas/air mixture coming out the plug hole. It might ignite, so be careful. If no spark, check to see if there is a wire shorted somewhere in the safety circuit. Usually they ground the ignition primary. A cracked spark plug wire can also be an issue - might be shorted somewhere, or jumping the gap elsewhere than the plug. Mowers are usually a version of a magneto ignition, with the main bits hiding under the flywheel. Again, an exploded diagram will be helpful to dis-assemble and find the bits to check.

Air is easy to check - try starting without the filter (after putting the plug back in and hooking it back up, of course). Also make sure the choke operates correctly.

Fuel - try to start it - and keep it running, briefly - with starting fluid or carb cleaner. If it runs when sprayed, but quits when you stop spraying, the fuel system isn't letting gas into the engine in sufficient quantity. You can also try to start with the choke on, and see if you need to keep the choke on to keep it running. If you do, it also isn't getting enough fuel and the choke is restricting the air enough to get a runnable mixture. Time to check and see if the clean gas cleaned your gas tank and deposited the gunk in your freshly cleaned carburetor, or the fuel line is deteriorating and dumping bits of itself in. Easiest is to pull the float bowl off and check for gunk. You might need to clean it again.

My push mower would plug up every other season or so and need the bowl pulled and the main jet (that held the bowl on) sprayed out. I knew it was time to do that when I either had to kick it regularly when it was about to die (dislodged the gunk briefly) or reach down and pump the primer to keep it running.

The gasket that seals the carb to the engine can also get damaged when you take the carb off to clean it, causing a too-much-air condition, which acts the same as a not-enough-fuel condition. If you didn't take the carb off, then this isn't likely to be the problem.

Check also for a split/cracked "pulsation tube" or similar that provides fluctuating crankcase pressure to a diaphragm that does fuel-pump duty. The diaphragm could be on the carb, on the engine, elsewhere - an exploded parts diagram would help. I patched mine with some self-adhering rubber tape. Symptoms will be the same as a not-enough-fuel condition.

Good luck!

[Xist]

Cajun, do you have a Ph.D. in lawnmowery? You just gave me more information than I have found in hours of research! Mom has far worse problems right now, but I have not figured out anything that I can do about them. At least I can fix her lawnmower!

[freebeard]

This picture tells it's story. The reel cut end is sheared evenly and will minimize water loss through the lawn. The rotary end is just beat and shredded.

[roosterk0031]

The last few I've tossed I had to really rip the cord to start, the few I pulled the heads off because I thought it was leaky valve seats had very little valve lift. Others couldn't start them at all, but a fast enough pull they would start but low power output and if bogged down would die. I had a Ninja 250 act similar when the valves where too tight (the day I bought it).

Had a snapper rider I couldn't keep the head bolts tight and would start leaking. Mice packed the housing with fiberglass insulation. Once cleaned and bolt tightened it was fine.