Author Topic: plug fell out, precautions prior to installing?  (Read 10379 times)

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Offline alexander-vmann

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plug fell out, precautions prior to installing?
« on: August 08, 2015, 04:01:25 AM »
took my bike to the track for the first time, was also the first time i've been riding on a track for a full year, i was going to take a last lap before heading home and at the start line it sounded like a airplane breaking down or a cartoon car, turned out to be the plug falling out of the top, so what should i do before i install it again to make sure it does not fall out again?
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my bike: 1993 kx500

Offline Foxx4Beaver

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Re: plug fell out, precautions prior to installing?
« Reply #1 on: August 08, 2015, 06:21:22 AM »
before you attempt screwing in another plug, you better be very sure the threads aren't all chewed up...or you'll be letting pieces of your head/threads go right in on top of the piston...and a new plug will shoot out again.
If they look good, put a NEW plug back in...not your old one....since the old one's crush gasket/washer is now done.
Excuse me, ma'am...but you've got extremely nice legs!!!...what time do they open???                                                                                                               https://www.youtube.com/watch?v=n8tCgN3aryQ

Offline alexander-vmann

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Re: plug fell out, precautions prior to installing?
« Reply #2 on: August 08, 2015, 07:04:24 AM »
before you attempt screwing in another plug, you better be very sure the threads aren't all chewed up...or you'll be letting pieces of your head/threads go right in on top of the piston...and a new plug will shoot out again.
If they look good, put a NEW plug back in...not your old one....since the old one's crush gasket/washer is now done.
i was able to screw back in the old plug, so i could wash the bike, did not tigthen it up but the treads felt good, so i migth be lucky and avoid debrie on top of the piston  :| i think what happend is that i did not tightn the spark plug good enough the last time i took it out, and its been vibrating its way out of the cylinder, but i could very well be mistaken  :|
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Offline Foxx4Beaver

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Re: plug fell out, precautions prior to installing?
« Reply #3 on: August 08, 2015, 07:15:36 AM »
I'd pull the tank off so you can get a GOOD look at the threads in the head....no sense rolling the dice when it only takes a couple minutes to do.
Chances are, it's ok...but it's better to be sure it's all set, than to have the plug shoot outa there when you're going wide open later on down the road.
Excuse me, ma'am...but you've got extremely nice legs!!!...what time do they open???                                                                                                               https://www.youtube.com/watch?v=n8tCgN3aryQ

Offline alexander-vmann

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Re: plug fell out, precautions prior to installing?
« Reply #4 on: August 08, 2015, 07:30:28 AM »
I'd pull the tank off so you can get a GOOD look at the threads in the head....no sense rolling the dice when it only takes a couple minutes to do.
Chances are, it's ok...but it's better to be sure it's all set, than to have the plug shoot outa there when you're going wide open later on down the road.

definatly agree with you there, gonna see if ''biltema'' has a new plug for me tomorrow and ofcourse take of the tank to inspect the threads
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my bike: 1993 kx500

Offline alexander-vmann

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Re: plug fell out, precautions prior to installing?
« Reply #5 on: August 10, 2015, 03:57:49 AM »
starting to wonder what plug i should get, i got a manual for a 93 model wich says b8eg/br8eg is standard, but my engine is a 87 mod, so wich plug would i be best of with? and does the air temprature have anything to say for heat range of the plug? it's a lot colder here in the winter  :|
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my bike: 1993 kx500

Offline alexander-vmann

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Re: plug fell out, precautions prior to installing?
« Reply #6 on: August 11, 2015, 12:05:03 PM »
i took of the tank and used a flashligth to look at the threads, thay seem fine just a bit brown at the bottom but the plug is supposed to be brown so i dont think thats unnormal, i should get a br8eg in the mail tomorrow, and maybe be ready for the track at thursday...hopefully :roll:
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my bike: 1993 kx500

Offline Foxx4Beaver

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Re: plug fell out, precautions prior to installing?
« Reply #7 on: August 11, 2015, 12:10:27 PM »
you should be all set....you said you were able to screw the old one back in without any resistance...you'll be good.
Excuse me, ma'am...but you've got extremely nice legs!!!...what time do they open???                                                                                                               https://www.youtube.com/watch?v=n8tCgN3aryQ

Offline alexander-vmann

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Re: plug fell out, precautions prior to installing?
« Reply #8 on: August 12, 2015, 09:19:50 AM »
so i got the new plug today and i dont understand this gap thing, in the manual it says it's supposed to be 0.5mm but that can't be rigth? it would weld itsself shut? so i just installed the plug without gaping it and it was a bitch to start, temprature was about 17-20 celcius so it migth be a bit rich but still
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my bike: 1993 kx500

Offline Foxx4Beaver

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Re: plug fell out, precautions prior to installing?
« Reply #9 on: August 12, 2015, 09:24:29 AM »
gap should be .024....or 0.6mm to 0.7mm.
Excuse me, ma'am...but you've got extremely nice legs!!!...what time do they open???                                                                                                               https://www.youtube.com/watch?v=n8tCgN3aryQ

Offline alexander-vmann

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Re: plug fell out, precautions prior to installing?
« Reply #10 on: August 12, 2015, 09:38:17 AM »
gap should be .024....or 0.6mm to 0.7mm.

thats still very litle, i migth have meassured it wrong then  :| but how do i bend the outer electrode without damaging it?
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my bike: 1993 kx500

Offline Foxx4Beaver

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Re: plug fell out, precautions prior to installing?
« Reply #11 on: August 12, 2015, 09:41:53 AM »
if you don't have a "good" gap tool...then you can pry it out very gently with a flat head screw driver...or if you have to go in, tap it very gently on a piece of oak....emphasis 'GENTLY".

when you do enough of em, like some of us on here, you can do it by eye.
« Last Edit: August 12, 2015, 09:47:20 AM by Foxx4Beaver »
Excuse me, ma'am...but you've got extremely nice legs!!!...what time do they open???                                                                                                               https://www.youtube.com/watch?v=n8tCgN3aryQ

Offline umberto

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Re: plug fell out, precautions prior to installing?
« Reply #12 on: August 12, 2015, 09:42:10 AM »
You need a tool like this.  You put the plug on one side and then slowly slide it towards the gap you need.  You can buy them at auto parts stores.

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Offline alexander-vmann

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Re: plug fell out, precautions prior to installing?
« Reply #13 on: August 12, 2015, 09:48:10 AM »
You need a tool like this.  You put the plug on one side and then slowly slide it towards the gap you need.  You can buy them at auto parts stores.



but the gap is definatly to big :|
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my bike: 1993 kx500

Offline alexander-vmann

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Re: plug fell out, precautions prior to installing?
« Reply #14 on: August 12, 2015, 09:59:10 AM »
could 0.7 mm be rigth? i mean thats almost not even a gap it's not even a single millimiter! the standard br8eg gap is definatly over a mm! maybe even 1,5mm ! and the bike is hard to start but it runs! so could 0.7 really be rigth?
KX 500 newbie

my bike: 1993 kx500