Lawnmower jammed - help! :)

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xpd

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#208901 4-Mar-2017 14:58

Bear in mind I am no mechanic/handyman so Im using layman/basic terms to describe stuff :-p

Lawnmower starter cord came out few weeks back, got it sorted, went to start and found the main "shaft" thing (the part at the top that the cord spins to start the engine that then runs down to the blade giving it rotation) wouldnt turn.... eventually found I could turn it by hand and it came loose, put lawnmower back together and away everything went........ until today.

Found its jammed again - so gave it bit of a whack with a hammer and it came loose again, thought "yay" put back together again, pulled cord, spun once, then jammed again.

Any ideas what I should be looking at to resolve this ? Or will be a shop job ?

TIA :)

That round center part is what Im trying to describe :-p (not my pic)

Gavin / xpd / FastRaccoon / Geek of Coastguard New Zealand

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#1729948 4-Mar-2017 15:01

Disconnect the spark plug and see if it will turn from the blade end. If thats jammed too then its probably a siezed motor.

Richard rich.ms

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#1729949 4-Mar-2017 15:07

That's the crankshaft - if that won't turn, the motor is seized or obstructed.

It could be something as simple as debris tangled in the blade underneath (have a look under the mower, careful with your fingers!), to a complex internal failure.

You could try unscrewing the sparkplug, preferably with a sparkplug socket, but a crescent will do if you are careful and look down the hole with a torch. You should be able to see the top of the piston moving up and down as you turn the crankshaft - if the crank moves, but the piston doesn't, you have a major problem.

Is the starter assembly detachable? That's the bit that has the pull cord and return spring in it. Some engines you can remove that entire assembly with a couple of screws, and it could be worn and jamming.

You could try Roundup instead of a mower - only have to use it once a year then

richms

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#1729954 4-Mar-2017 15:23

RunningMan:

You could try Roundup instead of a mower - only have to use it once a year then

Nahh, thats crap. There is other stuff that is more effective but I have never seen anything remain vegetation free for more than about 6 months even when putting some nasty stuff from RD1 on at well over the coverage that it was supposed to be done at. And worse is that what does grow back is usually some hard prickelly thing or blackberrys or something equally nasty. The true solution is concrete but it is very pricy.

Richard rich.ms

xpd

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#1729969 4-Mar-2017 16:17

Arse so not sounding good. On the plus side, I do have a spare lawnmower engine..... body was shot so we bought this other one second hand. So if the engine is stuffed, might be able to swap them over (similar engine) with a mates help.

Gavin / xpd / FastRaccoon / Geek of Coastguard New Zealand

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cadman

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#1729995 4-Mar-2017 16:29

Given the text "not my pic" have you removed the pull cord assembly like in the photo and checked that the crank is free to turn?

If it is free to turn, then it's just the mechanism in the pull cord that needs attention.

If it's not turning freely with the pull start removed, check the blade or shaft isn't entangled in the underbody.

wally22

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#1730014 4-Mar-2017 17:38

Could be that something has dropped into those cooling vanes as in picture and jammed it. If you can't see all of the vane then maybe dismantle further?

xpd

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#1730025 4-Mar-2017 18:04

Yeah, the crank is stuck solid, dont think anythings stuck anywhere.

Will get a mate to take a look throughout the week and go from there.

Gavin / xpd / FastRaccoon / Geek of Coastguard New Zealand

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richms

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#1730026 4-Mar-2017 18:08

You did have oil in it?

Richard rich.ms

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#1730076 4-Mar-2017 19:57

xpd:

Yeah, the crank is stuck solid, dont think anythings stuck anywhere.

Will get a mate to take a look throughout the week and go from there.

Did you try turning the blade? If the cord thingy is jammed that could be the cord thingy but if the blade wont turn, then the lawnmower thread here is for you!

If a mate can swap engines thats handy, as long as they all mount the same, which is kind of doubtful.

kiwirock

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#1730101 4-Mar-2017 20:48

If the blade is not obstructed, I'd pull the recoil starter to bits, sounds like it's jammed up.

At least then you'll know if the crank is rotating without it or not.

Especially if you were able to run it again after a few banging attempts and what not.

Otherwise I'd suspect valve train or oil jammed in cylinder (remove spark plug to check).

If it was anything more serious, like the blade's hit a few too many chunks of concrete that killed the motor (bent connecting rod) or lack of oil seizure, then a second hand swap might be easiest.

Some small bore motor repair shops are quite reasonable. I've had a mower picked up, fuel tank and carb replaced with throttle cable by my local hardware store and re-delivered for $120 (second hand parts). It's not like there's a lot to pull a mower engine to bits if it's something mechanically jammed providing the parts are around.

I wouldn't' be surprised if it's just the recoil starter though.

Batman

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#1730121 4-Mar-2017 21:39

when did you last change the oil in the motor?

kiwifidget

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#1730259 5-Mar-2017 09:36

http://ecolawn.nz/

I hate any tool that has one of those pull cord start thingies.

Delete cookies?! Are you insane?!

neb

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#1732780 7-Mar-2017 22:25

richms:
RunningMan:

You could try Roundup instead of a mower - only have to use it once a year then

Nahh, thats crap. There is other stuff that is more effective but I have never seen anything remain vegetation free for more than about 6 months even when putting some nasty stuff from RD1 on at well over the coverage that it was supposed to be done at.

There's one very effective way to get rid of weeds, including roots, spores, and all other organic matter. You just need to apply a bit of sodium-24, which you can manufacture on the spot from natural sodium, Na-23. What you do is build up alternating layers of sodium and lithium deuteride and ignite it. The resulting Na-24 has a half-life of only about 15 hours, so you can re-enter the area after a couple of days and all your weeds will be gone since it produces staggering amounts of high-energy gamma radiation as it decays. The weeds most definitely won't come back.

The one downside is that sodium has a tiny neutron capture cross-section, so you need to make the sodium/LiD layers quite thick in order for this to work. This means you may inadvertently kill some of your neighbours' weeds in the process.

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#1732868 8-Mar-2017 09:52

neb:There's one very effective way to get rid of weeds, including roots, spores, and all other organic matter. You just need to apply a bit of sodium-24, which you can manufacture on the spot from natural sodium, Na-23. What you do is build up alternating layers of sodium and lithium deuteride and ignite it. The resulting Na-24 has a half-life of only about 15 hours, so you can re-enter the area after a couple of days and all your weeds will be gone since it produces staggering amounts of high-energy gamma radiation as it decays. The weeds most definitely won't come back. The one downside is that sodium has a tiny neutron capture cross-section, so you need to make the sodium/LiD layers quite thick in order for this to work. This means you may inadvertently kill some of your neighbours' weeds in the process.

Sounds like a neat idea. Would it be effective on the neighbours as well as their weeds?

MikeAqua

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#1732891 8-Mar-2017 10:31

kiwifidget:

http://ecolawn.nz/

I hate any tool that has one of those pull cord start thingies.

Do you have to clean that stuff occasionally?

Mike

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