Any SI engine you fancy doing it to - Cleaning Spark Plugs

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Mon 20 Mar 2023 01:39
Any SI engine you fancy doing it to - Cleaning Spark Plugs - edlithgow

Deeply unfashionable now, of course, but used to be mainstream, with the likes of Halfords even selling wee sand blasting gizmos for it.

Never had one of them, or a gapping tool, but I think I had a wee brass brush and used a nail file, maybe a pick down the plug recess.

I suppose with plug access becoming difficult on many cars, and longer life plugs, plug cleaning went off-message, and manufacturers started warning about creating metal tracks on the insulator. `Cleaning is still mentioned in the handbooks of the sort of ancient cars I have bought though.

Attempting to revive the art, I used a hypodermic syringe with a long wide blunt needle (sold at Daiso makeup section for unknown and probably scary purpose) to fill the plug nose with coffee-filtered old brake fluid, plugs stood nose up in a plastic beaker. Periodically skoosh some more in, re-using the overflow from the bottom of the beaker.

The brake fluid gets VERY black.

You could use a conventional hypodermic for this, its sharp tip would make a better pick, and you could probably generate more pressure (screw-on needle only) as I do for carb cleaning, BUT if you tried recycling the fluid your needle would probably block.

Next day I boiled them with detergent for half an hour or so and then attacked the nose with a (probably rather harsh) stainless steel brush. The boiling didn't do anything obvious.

Came up looking pretty clean.

Doing it again, I'd use a brass brush and boil afterwards, cleaning with a toothbrush to hopefully help remove those (mythical?) metal tracks.

Not A LOT of trouble, but if I had a good blowtorch burning off might be easier.

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Wed 5 Jul 2023 06:34
Any SI engine you fancy doing it to - Cleaning Spark Plugs - Bolt

Halfords even selling wee sand blasting gizmos for it.

I think others did one as well but in the time the gizmo took to do the job you could do it faster yourself, just as quick to use emery cloth/wire brush to clean the plug and gap with feeler gauge job done and re install

Doing it again, I'd use a brass brush and boil afterwards, cleaning with a toothbrush to hopefully help remove those (mythical?) metal tracks.

No point, if the tracks are there nothing you can do about them just clean with emery and gap/wire brush then re install simple, often see people faffing about with plugs often not worth the effort but if they work and don`t short its easier

Mind you some don`t even check they leave in place and wait for failure.

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Wed 5 Jul 2023 09:31
Any SI engine you fancy doing it to - Cleaning Spark Plugs - catsdad

It’s funny that years ago when plugs were cheap I used to clean them rather than replace. I even tried the useless mini sand blaster but settled on wire brushes and emery paper. Now plugs cost a ruddy fortune and I pay someone to replace them according to the manufacturer recommendations. It’s the way of the world.

They do last a lot longer though nowadays. Plug and fuel quality and ignition systems having improved. However when I worked in car rental in the 70’s with a fleet under a year old we had a contract with a local garage who did us “points and plugs” services on demand. We lost half an hour rather than a day at a main dealer. Most cars needed these at about six months old and the improvement in running and reliability was immediate.

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Wed 5 Jul 2023 10:03
Any SI engine you fancy doing it to - Cleaning Spark Plugs - Andrew-T

Ed, perhaps you could beg or borrow an ultrasonic bath ?

I still have a small (probably Japanese) tool with a small brush for cleaning plugs and checking the gaps. No idea when I last used it, if I ever did (think I must have).

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Wed 5 Jul 2023 10:28
Any SI engine you fancy doing it to - Cleaning Spark Plugs - sammy1

In case you have not noticed spark plug tech is now in the 21 century and just the fact of removing plugs and re-fitting them can give you a bigger headache than leaving them alone. But if that's your way just carry on tinkering. More to the point is that car running yet?

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Thu 6 Jul 2023 17:25
Any SI engine you fancy doing it to - Cleaning Spark Plugs - gordonbennet

Plugs are in too long now, serious danger of them breaking off in the head, it happens too often with Subarus and i dare say other designs that are difficult to access plugs which tend to get ignored until running troubles.

Can't find it any more i used to have a plug thread tool, double ended for the two sizes, used to send it down the thread which kept it nice and clean.

Speaking of plugs, what's the best practice now re putting some sort fo anti seize or coppaslip on the threads when fitting new plugs which might be in there for many years.

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Sat 8 Jul 2023 03:00
Any SI engine you fancy doing it to - Cleaning Spark Plugs - edlithgow

Plugs are in too long now, serious danger of them breaking off in the head, it happens too often with Subarus and i dare say other designs that are difficult to access plugs which tend to get ignored until running troubles.

Can't find it any more i used to have a plug thread tool, double ended for the two sizes, used to send it down the thread which kept it nice and clean.

Speaking of plugs, what's the best practice now re putting some sort fo anti seize or coppaslip on the threads when fitting new plugs which might be in there for many years.

I think ill be putting aluslip on them if the car ever runs again, maybe some foil too. NGK say the plating makes antiseize unecessary, but cant see it being harmfull unless it causes you to over torque them. I dont use a torque wrench anyway and id think my wire brushing might have compromised the plating. I suppose I COULD break down and buy new plugs though. Only 3 after all

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Fri 7 Jul 2023 01:29
Any SI engine you fancy doing it to - Cleaning Spark Plugs - edlithgow

In case you have not noticed spark plug tech is now in the 21 century and just the fact of removing plugs and re-fitting them can give you a bigger headache than leaving them alone. But if that's your way just carry on tinkering. More to the point is that car running yet?

Yes, I have heard that this 21st century automotive technology thing wasn't working out too well.

Thankfully I've managed to avoid it so far..

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