Page 1 of 1

Plug Caps

Posted: Wed Oct 16, 2013 6:19 am
by Boomlander
Hi Folks..... May be a daft question but are spark plug caps "one size fits all "or are they specific to their own brand of plug, NGK Champion Etc.
I ask because I have Champion plugs fitted and bought a set of NGK waterproof caps to replace the naff plastic ones that were on the leads originally. The new caps will not fit tightly onto the plug nipples. :-? :-?

Re: Plug Caps

Posted: Wed Oct 16, 2013 9:07 am
by bmcecosse
One size fits all normally.

Re: Plug Caps

Posted: Wed Oct 16, 2013 1:05 pm
by JOWETTJAVELIN
You can carefully adjust them with pliers or thin screwdriver to make a good snug fit.

Re: Plug Caps

Posted: Wed Oct 16, 2013 1:18 pm
by simmitc
And don't forget that plugs have a screw on terminal at the top, and can be used with just the threaded bit, or with the bulb shaped bit. This gives different fits for different caps.

Re: Plug Caps

Posted: Wed Oct 16, 2013 2:23 pm
by Boomlander
Thanks for the advice - much appreciated :D

Re: Plug Caps

Posted: Wed Oct 16, 2013 5:32 pm
by M25VAN
I've just made up some leads and used LZFH NGK caps. These fit straight on to the thread on the plug top so you have to remove the bulb shaped bit for these.

Re: Plug Caps

Posted: Wed Oct 16, 2013 5:58 pm
by bmcecosse
I've never seen caps that don't use the 'bulb nut' - and indeed I have some plugs where the 'bulb' is not removable !

Re: Plug Caps

Posted: Wed Oct 16, 2013 6:28 pm
by MarkyB
Really? I haven't seen any in a while but they do exist, maybe more on motorbikes than cars.
Removable bulb nuts need nipping up with pliers (unless a special tool exists :) ) or they can come loose.

Re: Plug Caps

Posted: Wed Oct 16, 2013 7:01 pm
by bmcecosse
I just give them a smart whack with a chisel...... :lol: :lol: :lol:




And for those that don't know me.......this is a joke -not to be taken as serious advice (in this case). :roll:

Re: Plug Caps

Posted: Wed Oct 16, 2013 8:23 pm
by MarkyB
LOL, that's your answer to everything :D

Re: Plug Caps

Posted: Wed Oct 16, 2013 10:52 pm
by bmcecosse
Well - NOT THE COIL - obviously........ :oops:

Re: Plug Caps

Posted: Wed Oct 16, 2013 11:35 pm
by JOWETTJAVELIN
I believe the plugs with screwable tops enable them to be used on very old cars with a ring connection to the plug; you often see them on pre-war vehicles where the HT leads are insulated with cloth.

Re: Plug Caps

Posted: Thu Oct 17, 2013 8:31 am
by M25VAN
bmcecosse wrote:I've never seen caps that don't use the 'bulb nut' - and indeed I have some plugs where the 'bulb' is not removable !
I'd had problems with cap connectors rusting, coming loose and the bulb on the top of the plug continually coming loose. Thought I'd try these caps as the connection part is made of brass so shouldn't corrode. They take a bit of pusshing on so have made good contact. Time will tell if they remain as tight after a removing a few times. Also the rubber plug seals are are better fit than I had before.

Re: Plug Caps

Posted: Thu Oct 17, 2013 12:11 pm
by bmcecosse
Sounds good - can you 'point' us to them on the internet?

Re: Plug Caps

Posted: Thu Oct 17, 2013 6:25 pm
by Ufudu
Here are aftermarket NGK plug caps with built in suppressor that need the bulb nut of the spark plug removed.

It's a 2L LR S1 motor. I'm not 100% sure but I somehow think the original Land Rover Series 1 plug tops were similar.[frame]Image[/frame][frame]Image[/frame]

Re: Plug Caps

Posted: Thu Oct 17, 2013 8:16 pm
by bmcecosse
Interesting!

Re: Plug Caps

Posted: Thu Oct 17, 2013 8:21 pm
by M25VAN

Re: Plug Caps

Posted: Sat Oct 19, 2013 4:37 pm
by Boomlander
Ufudu wrote:Here are aftermarket NGK plug caps with built in suppressor that need the bulb nut of the spark plug removed.

It's a 2L LR S1 motor. I'm not 100% sure but I somehow think the original Land Rover Series 1 plug tops were similar.[frame]Image[/frame][frame]Image[/frame]
You are absolutely correct... these plug caps will only lock on to the threaded portion of the spark plug with the screw on nipple removed!
You learn something new every day.......Thank you. :D :D