Lawnmower LED Light Bulb - Failed A Third Time!

My lawnmower came with an LED headlight. I think it was designed more to help others see me than to light up the area in front of me. I’ve mowed a couple times when towards the end became dark and the headlight barely helped, but was better than nothing.

Then earlier this summer I noticed that the headlight started to flicker. The 1156 sized bulb has 19 LEDs in it and at first about a quarter of them started to flicker and turn off and then as you can see only 7 remained.

So I looked for a replacement bulb and given that I’m a BLF member and we like lumens, I figured an improvement was needed. I found these 1206 SMD LED bulbs with various designs and number of LEDs, from 22 up to 127 LEDs. I wanted to keep the size of the bulb similar to the current one, but also lean on the side of maximum LEDs. I also wanted warm white vs cool white, but that was not available with the design I chose - a whopping 85 LED bulb for less than $2 on eBay!

I installed it and was very impressed. It is a lot brighter than before and more than adequate to mow the lawn when it gets dark.

Nice mod NF. Your neighbours must love you mowing the lawns at night. :+1:

with the fire restrictions around here we can’t power mow 10AM to 8PM
I’m NOT a morning person, so given the option of mowing 8PM to 10PM
iffn I had adequate LEDs I just might query my 4 affected nabors to see what they preferred
although my acre of grass is only as high as an elephant seal’s eye presently

Would you mind explaining to someone from a wet place without fires how those two are related? Are lawnmowers known to start fires or something???

I prefer to mow on the weekends in the afternoon once the grass is dry, but when it’s growing crazy like it did this summer, I also need to mow during the week after work. And sometimes there are kid duties, so it gets pushed back even later, and now this time of year, sunset is a little after 7pm.

I try to be a good neighbor so it’s rare that I’m finishing up in the dark.

I have mowed a fair share of grass in my day. It’s not uncommon for a Briggs engine to backfire and shoot a flame after it has been running on full throttle and quickly put into low throttle.
Not saying its impossible for a fire to start from that but for it to happen that grass certainly hasn’t been growing and didn’t need cutting. It would be dead and dried out.

I got these for my rear-firing reverse lights on my car. Quite nice, aims the light where it needs to go vs relying on a reflector to do the heavy-lifting.

Would seem to be a better “fit” for your mower, as the original was that way, too.

Thanks for the suggestion Lightbringer. If the new bulb goes bad, I may get them. When I was doing my research, I saw the bulbs with the lens in front, but wasn’t sure if they would be bright enough or if they would have too narrow of a beam.

I have also put out quite a few sparks hitting rocks hidden in tall grass. :cry:

Well today when I was cutting the lawn (first time since I replaced the bulb) I noticed that the new bulb started flickering. Looks like 6, maybe more, LEDs on one side. The lawnmower must vibrate too much for the bulb. There are lots of solder joints on the bulb so I guess this was inevitable. Disappointing nonetheless.

This is what Lightbringer was suggesting. Looks pretty good, not too expensive, and should hold up better. Plus it should put more light in front of the lawnmower where it’s needed.

Any other suggestions?

Hmm, that stinks. Sorry to hear that. Didn’t think soldered LEDs would give it up that fast.

Yeah, I had these a coupla years already, and thank B’harni (pbuh!), haven’t had the slightest hitch.

The lens is pretty close to the LED, so they do put out a fairly wide field of light. Quite nice for reverse-lights, actually.

Nice thing about the 2-pack is that even if one goes south, you still got another. :smiley:

Thats a shame NF. Thanks for reporting back the results and good luck with the next ones. :+1:

After too many hours of research on Amazon and eBay, I have found these that look very good:

But there’s no way I’m paying $27 for them.

My new bulb(s) came in the mail today. BTW, the eBay seller that sold me the 85 SMD LED bulb gave me a full refund. Here’s the defective bulb (I count 8 LEDs bad):

Here’s the defective replacement bulb with the lawnmower lens on (left) and lens off (right)(10 sec, F/20, ISO 1600):

Here’s the new bulb with the lens on (left) and lens off (right):

Again, here’s the defective replacement bulb with the lawnmower lens on (left) and lens off (right)(10 sec, F/18, ISO 1600):

Here’s the new bulb with the lens on (left) and lens off (right):

Here are my observations:

  1. The new bulb gets a lot warmer than the defective bulb.
  2. The new bulb is significantly brighter.
  3. Even though they are both cool white, the new bulb is less cool and shows the green of the grass better.
  4. The lawnmower lens kinda sucks. Even though it helps disperse the light, there are streaks that are noticeable with the new bulb.

The new bulb is certainly much better than the original bulb that came with the lawnmower. Rarely do I end up mowing in the dark, but it’s nice to have the extra light when needed.

Thank you Lightbringer/BLF for your help.

No worries, glad to help.

I’m betting that the (facetted) lens is meant to take all the light that’s bouncing around in that 5-sided cube (ie, 6th side missing) and just scatter it as best it can. Enough random bounces, and it’s “smooth”.

The bulb with a brazillion discrete LEDs all over, around, on top, everywhere, similarly threw light everywhere, to again bounce around the mirrored cube and out the front lens.

Now with a single point-source throwing light just out the front, the front lens is acting like a chopper for those pyroelectric person-detectors (alarms, auto-on lightswitches, etc.), ie, a “fan” of individual beams directed all over the place. So now, all those light/dark areas show up really well. :smiley:

If you can stick just a clear piece of plexiglass or something over it, to keep out grass clippings and other filth, you can have that nice smooooth light courtesy of the bulb’s aspheric lens. :smiley:

Good idea ! But It’s just to be beautiful. I think the effect is not high

Thanks for the suggestion. Another option would be to put something inside the lawnmower lens to smooth things out. Or if I really wanted to be experimental, I could sand down the inside of the lens, but that seems too risky. I’ll see what I have to put inside the lens and see if that helps.

Good luck with the latest leds. Its bound to be mentioned, DC fix though in this case it may not work.

Last week I noticed the headlight was no longer working on my lawnmower. So I pulled off the headlight lens (it’s glued in) and looked at the LED bulb.

Well no wonder why, the LED fell off the MCPCB (see bottom left corner)! Wow, that must’ve gotten very hot in order to do that. My guess is that MCPCB must have dislodged from the bulb shelf due to the lawnmower vibrations and overheated. I see there’s nothing to secure the MCPCB to the shelf.

So it was my first opportunity to reflow a LED. I don’t have solder paste, so I tinned the MCPCB and put some flux on the bottom of the LED. Held it over my heat gun and as soon as the solder melted I took it off. It looked pretty good.

Since the bulb is essentially a hollow shelf flashlight, I wanted to improve the heat management. I found a washer that fits on the shelf, made some notches for the LED wires, flattened both sides, and used some thermal compound next to the MCPCB. I then used 2 very small screws to wedge the MCPCB and washer against the bulb shelf.

I also sanded down the aspheric plastic lens and made it frosted. The beam was too narrow before and showed lots of artifacts.

I’m happy to report that my reflow worked and the beam looks much better. Time will tell if my heat management mod actually makes a difference.

You sure that socket is a steady 12 volt dc? Might be running off the ac side of the stator and that could be the cause of some of your issues.