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I have had for some time now the air compressor that you remove a spark plug and screw it in and start the engine. I used it the other day and it was actually much quicker than a cheap 12v compressor to inflate a tire. Is there any reason no one else seems to use these compressors.

The only downside i can see is it can be a little tricky to fit it on a hot engine.

That and its a pain in the bottom (maybe)
Would there be some issues with the other chemicals being pumped into the tyre - not just air, CO2 ect.

i dont belive so as its actually a little diaphragm pump run from the compression in the cylinder not just directly using the compression in the cylinder.

and .. arent you meanting to be fitting a new steering rack.

See other thread.

Things I can see wrong with it, without even seeing it.
Not all vehicles have spark plugs.
I would hate to sit there cranking the crapper out of my little starter motor to pump up small tyres, let alone a real 4x4 tyre.
You can buy good 12 volt compressors now.
You can buy endless air kits
You can buy Air-Up kits.

the engine will run on 3 cylinders np so you dont have to crank starter.
My car does have plugs
its alot cheaper than good compressor i think.

I don't like the idea, but then I don't have one so I don't need to like it

I had one for a while and they were great with the EA81 where you could get at the spark plugs easily.
It used a diaphram and pumped fresh air into the tyre.
No problem to run the engine on three and it was way faster than a 12v compressor.
It fell out of favour though with the EA82 as the plugs were more difficult to get to and the engine always seemed hotter.
Would be nigh on impossible now with the plugs in the Outback.

They were a great idea in their time, but over the years receeding spark plug placements and the popularity of diesel have probably caused their demise.

Somebody needs to invent a special spark plug that functions as a spark plug AND a compressor. So it's permanently installed (until it needs changing like a normal plug) and has a valve that can be easily opened or closed to turn the air on and off. It could have one of those quick fit attachments like you get on air compressors.

Quick quick, I better run to the patent office!

I think something like that would have to be a modification to the head not the spark plug. I don't think u can mess around with the actual location of the plug.

Dave

SuBaRiNo wrote:I think something like that would have to be a modification to the head not the spark plug. I don't think u can mess around with the actual location of the plug.

Dave

Speaking of that - Nissan and Toyota know that their cars are used offroad (except for soccer moms) so maybe they should look at incorporating a air-up sytem into their heads, would be a reason to choose one over the other when it came time to get a big fourby...

If the plug fired you would have a flame front heading down into your compressor......it would need to be made of somthing very tough to survive combustion pressure let alone a very hot flame front ! ...what if it got charged with fuel and then ignited.... BANG !

I have used these pumps before, on older landcrusiers etc....pain in the arse on a hot engine, and I`m pretty sure its not real good for your engine to be running with a dead cylinder and fuel still getting in there to wash your rings etc....... wouldn`t do it to a newer car !


OS

I'm going to try for the old "endless air" trick. I've got 3 or 4 air-con compressors here, just gotta try to squeeze one in the engine bay somewhere.

or in the new trailer