Author Options:

My lawnmower left me saying "WTF" this morning... Answered

Well, here's the deal.. Last night I took the mower deck off my rider, sharpened the blades, re-attached them, made sure it ran fine, which it did, worked like it has been for the past 3 months, parked it in the tarp shed and went inside. Well this is what really really made me snap. I was happy with it because I just fixed the tire and thought "Thank fuckin god it's back and working again" as it had sat up on cinder blocks for the past 2 weeks due to flat tires. Morning comes, beautiful day out, grass to mow. I go to start it, takes a few times (I thought it was odd, but didn't think much of it) and get it started.

Well some past history first, this machine was fixed at a mennonite repair shop a year ago or so because apparently there was a peice of dirt stuck in the hole that a supposed pin drops into when the machine shuts off to stop the gas flow from going into the engine when it's off. They put a valve on the gas line aswell, well after that, it never went down all the way on the throttle or it would just stall. Well this morning, it seemed to be completely the opposite, it idled fine at the lowest throttle setting (I had a really confused look at the time) and at full open, it ran horrible and the whole frame was shaking because it was going up and down (the reving I mean). I tried to cut grass with it, and it goes for about 5 meters and then nearly stalls (still hasn't for some reason, but just barely) and then starts running again and spews out a shitload of smoke for a few seconds. I tried to "run" it off and it didn't even drained the gas and put new gas in, that was a wasted $10 trip to the gas station.

As of now, it's sitting out in my yard, I don't want to touch it because it's pissed me off enough. Also, I took the air filter off and it seems that at one point it was spewing gas up out of the air inlet. Can someone please help me?!? I need this machine running as I cut grass for people. I vowed to myself I would permantly park this thing if one more thing broke, but it's getting it's last chance.

** Forgot to add, it's a 12hp brigs and straton (type H I think?), and manufactured by murry (I know..sad).

Second update:

Uhhh...it appears to be fine?? It ran ok today, a bit touchy, but it seems ok, can someone care to explain how the hell this happened????!?, scrap that, it's fuxxored again. Arg, I need it for my lawn cutting needs!



11 years ago

Back to you old foul mouth again I see!

Ah...so it was you that got me banned on my other account was it? Don't push your luck ham taro

If you take that as a threat, then you really need to check into the padded room. I'm just simply telling you that you shouldn't push your luck. A threat would imply that I was going to do something directly to you ie: "I'm gonna beat you to death", aswell to add to that, that is merely an example.

Don't and shouldn't are two different things.

Give it up or I will have a few words for you.

Ahh... more threats.

ur just trying to annoy him hamO

You do realize he was posting that 3 years ago?

> so then it filled with gas . Not good. :( You may have scratched the cylinder wall and no telling what happened to the bearings. I'd start saving for a new engine or rebuild. . I'd run it for a few minutes and change the oil again, just to make sure you get rid of all the gas.

Well I checked the oil and it's fine, but I'm definatly gonna start using the fuel valve every time I put it away, the vacum should keep the gas in place.

Well, there a quite a few things that can go wrong with a two stroke engine. From your description above, an I could think of a few things, which might be wrong. If it is vibrating violently it could mean that the you put the lawnmower blade on at a angle, or that there is a bend somewhere in the blade you could compare it to the vibrators in a game controller . A uneven blade is very bad for a engine which may account for all the sputtering.Anoter reason for the problem could be a blocked carburetor that is not letting enough air out. As for the bad start up, I would say it was due to the gas becoming stagnate from sitting to long, or an undercharge battery. To guess the problem with the engine I could use some more information like what color is the smoke or what the end of the spark plug looks like.

First off, I seem to recall anything 4 hp and up being 4 stroke, hence takes regular gas. The blades are fine and cut like a charm, I meant, it was vibrating violently "withouth" the mower deck being engadged. That part is fine. I think it's letting lots of air out/in, I have to clean up my shed where I started it, it spat a whole load of gas out the exhaust when I started it and left a big black wet ring on a peice of plywood that was sitting by the exhaust. The gas, I just bought. Battery, was just charged aswell. The sparkplug was fouled so I cleaned it and put it back in with no avail, and I just bought the sparkplug last year. The smoke is nearly black, if it was lack of gasflow, it would be white wouldn't it?

Sorry, I missed the part where you said what type of engine it is. If it spit out gas from the exhaust pipe it probably means that there is poor cumbustion, or that there is too little or too much fuel being ingected.What was your sparkplug fouled with anyway. Black smoke means that there is too much gas being injected into your engine check your choke switch to make sure it is not jamed, or flush your carburetor out with carb cleaner there could be some obstruction in the airflow. Place a piece of paper over you carburetor to see if it is sucking. (In a good way)

I just fixed it, well I went to check the oil, and so I did and there was nothing stickin to the oil dipstick, so I undo the plug, and gas gushed out. What had happened was that the gas pushed all the oil out of my oil dipstick where it has a crack, so then it filled with gas. I'm surprised that a engine filled with gasoline actually worked. I took the exhuast off for shits and giggles, and it was full of gas man !, so drained that out before we had a fire. Long story short, It works now, put new oil in. I had a guy looking at it and he said that the float which is plastic is a little bent upwards, so it doesn't work properly, which was from the last problem and hence the fuel valve.

. If your engine is a 4-stroke, it won't have the reed valve I mentioned earlier. . > I think it's letting lots of air out/in . It's very hard to judge if it's the _right_ amount of air in/out, even if one has lots of experience. . > big black wet ring . Was it wet from gas or oil? . This is not uncommon in older "lawnmower engines" as the rings/valves wear. . > The sparkplug was fouled so I cleaned it . What was the color and consistancy of the crud on the plug? This will tell you more about the condition of your engine than anything else and it's easy to check. . Never clean a plug with a wire brush (or anything else that is conductive) - very common mistake. This may short out the plug. . A new plug would probably be a good investment. I'd get a spare while you're at it - the plug is likely to foul again before you get the problem fixed. . > The smoke is nearly black, if it was lack of gasflow, it would be white wouldn't it? . Black smoke is usually caused by oil contamination, but can be a sign of running very rich. Whitish smoke is usually a sign of being moderately rich. Lack of gas usually produces no smoke at all.


11 years ago

you should make a video of it trying to mow your lawn and maybe you will get more answers

You know what? I was out on it "trying" to cut grass and thought the same thing, they were calling for rain today, but the sun seems to be peeking out, so maybe I'll set the laptop and webcam out there and do just that.

Ever set your lawn mower up on cinder blocks and change the oil? Yes, there is a plug there, loosen it. You might be amazed how long your mower will last if you change the oil every year before you use it.

sigh... I just changed the oil a couple months ago fool, I praise this machine, I even wax the frame with some protectant and it keeps it nice and shiny.

I did, and it was all fouled up, so I cleaned the contacts with fine grit sandpaper, and sprayed it with wd 40 and then flushed it with gas and it did the same thing.

. I'm with lemonie - sounds like a dirty carb. It may just be some water in the fuel bowl, which may not require a complete teardown (some carbs even have a petcock for just that purpose). . If the "Mennonite pin" is not opening all the way it could cause the engine to starve at higher RPM (although your symptoms seem to indicate that you're running too rich). The valve in the gas line is a backup - I'm guessing that your gas tank is mounted rather high compared to the carb.

. Hey! Before you tear into the carb, check the governor. Usually a plastic or metal flap that sits next to the fan and limits the throttle when RPMs get too high. May not be the problem, but should be pretty easy to check.

I'm not sure if there's a governer. There's a lever that connects to a rod at the base of the engine on the carb side, about at the back of that side. It revs the engine when I pull it back, I've made it go past what the full throttle usually is. And I belive there ia a metal connect rod going over the the butterfly valve on the carb.

. That sounds like the governor and it sounds like it's moving freely. Oh well. Sometimes you get lucky and it's something easy. . It's looking more and more like a carb rebuild. :(

Well I figured, if the carb was dirty, then it would be getting less gas, but it's literally spraying gas out the air intake.

PS: gas out the intake may be caused by a broken/dirty reed valve (between the carb and cylinder).

. A dirty carb can do lots of funny things. Dirt in the inlet valve can cause flooding.

Well I emptied the bowl as I could get at that, but I need a socket set to take it all apart. I'm not sure what it was, when I went to put it away this evening, it ran nearly fine. I thought there was water in the gas, but I emptied the tank and bowl a second time and went up to the gas station and got $10 of gas and tried it again, wasted my money sadly. And I don't think the gas tank is much higher than an inch high.

In my experience of 2-strokes, cleaning the carb' often works. Take the carb' off, dismantle it and clean it very thoroughly. I don't think it's the air-filter because you've already taken that off and inspected it., "they put a valve on the gas line" sounds a bit like "they put a fuel filter in the gas line" or did they? Briggs and Stratton eh? nice! L

There was already a fuel filter in it, but they put a elbow valve on it. I've put the machine away for the night, we'll see if it runs tommorow I guess. And I want to take the carb off, but I can't becase I don't have sockts small enough to get a couple tiny bolts off that hold the air filter modual to the carb.