Cleaning and gapping spark plugs

Katamarino

Katamarino

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Katamarino
I've recently moved to the west side of Houston, which makes working with my previous mechanic in Pittsburgh less convenient. I carried out my first "solo" oil change yesterday, but don't have the tools (or knowledge) to clean and gap the spark plugs myself yet. If there's anyone nearby who could give a little coaching the first time I try it then I'd be happy to offer beer or other consideration!
 
Not near Houston but,,,,,buy a few tools first. Ask around your field for a hand with the plugs. Folks be glad to help or watch youtube on subject. Tools to start:
- plug tray
- gap tool
- anti seize
- plug socket

You can never buy enough tools. :D

NOTE: Drop a spark plug on the floor and its toast!
 
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Search on youtube for cleaning aviation spark plugs
 
I just did mine myself for the first time...I think it is actually easier than an oil change. In addition to the tools LT4247 mentioned, I would also include the plug cleaner itself...don't use a regular sand blaster!
 
tawood said:
I just did mine myself for the first time...I think it is actually easier than an oil change. In addition to the tools LT4247 mentioned, I would also include the plug cleaner itself...don't use a regular sand blaster!
Click to expand...
What is a "regular" sand blaster?

Jim
 
Witmo said:
Search on youtube for cleaning aviation spark plugs
Click to expand...

here's one:

He doesn't mention testing with meter for resistance, probably another one out there for that.
 
LT4247 said:
NOTE: Drop one on the floor and its toast!
Click to expand...

^Very salient point! It can be an expensive fumble...even a hairline crack in the insulator turns the plug to junk.

Google "aircraft spark plug rotation" and find a chart that shows the rotation pattern.
Get a pick-type tool for removing any balls of lead that accumulate around the base of the insulator.
 
Quick note:

If you're on a budget, its pretty easy to make a plug tray.

I made mine out of an old battery box. Originally 12 holes for my Cirrus, now just use 8, sleeved down, for my Sky Arrow.

26116187173_fe4a06a362_z.jpg
 
Don't forget new gaskets or at least anneal the old ones.
 
How do you clean your sparkplugs without a fancy plug cleaning sandblaster?
 
tawood said:
I think this:
View attachment 48144
Although it's not the blaster, it is the blasting material that causes the problem.
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There are numerous media that can be used in blasters. Glass bead is good and doesn't cut the plugs up too badly. It's hard to see and you have to be sure there isn't any stuck in the plug or it'll end up in the cylinder and do nasty things in there. Glass bead is spherical when it's new and even after it's broken into smaller bits it's not too sharp. I prefer it.

Most aviation plug cleaners use silicon carbide grit, which is really hard and angular and sharp and can damage the plug if it's blasted too long. Champion sells it for cleaning plugs.

Sand is dirty stuff and breaks down rapidly into dust.

There's a ground copper slag that's hard and sharp and black and shiny and it shouldn't be used on anything on an airplane. It's commonly used in the sandblasting industry because it can be reused many times. It really eats stuff quickly. And generates a lot of static electricity.
 
LT4247 said:
Not near Houston but,,,,,buy a few tools first. Ask around your field for a hand with the plugs. Folks be glad to help or watch youtube on subject. Tools to start:
- plug tray
- gap tool
- anti seize
- plug socket

You can never buy enough tools. :D

NOTE: Drop one on the floor and its toast!
Click to expand...

I occasionally drop tools on the floor, and continue to use them. Is that bad? ;) :D
 
FastEddieB said:
Quick note:

If you're on a budget, its pretty easy to make a plug tray.

I made mine out of an old battery box. Originally 12 holes for my Cirrus, now just use 8, sleeved down, for my Sky Arrow.

26116187173_fe4a06a362_z.jpg
Click to expand...

:yeahthat:
Love it!!

No pic, but I made mine using an inverted loaf pan. The cost of Champion or other spark plug trays are ludicrous.
 
GRG55 said:
:yeahthat:

No pic, but I made mine using an inverted loaf pan. The cost of Champion or other spark plug trays are ludicrous.
Click to expand...
You're right...I'd never buy one of those rip-off trays. Mine is a scrap chunk of 2x6 soft pine with holes sized for the plugs.
 
Sorry I don't have a picture - but my "spare no expense" plug tray is a piece of cardboard I tore off the top of a box. I poked 8 holes with a screwdriver and carefully labeled each hole with a half dried out Sharpie that was lying around the hangar. So far I've been using it for about 6 years - you need to be sure and get your money's worth out of high tech stuff like that.
 
As an aside, the NGK spark plugs for the ROTAX cost in the vicinity of $2.30 each.

Which means you can buy 8 for somewhat less than a single "real" aviation spark plug. And they seem to be at least as reliable.

What this means is it's a reasonable option to just go ahead and replace them for around $20 total rather than go through the effort of inspecting, cleaning and gapping the old ones.
 
SoCal RV Flyer said:
You're right...I'd never buy one of those rip-off trays. Mine is a scrap chunk of 2x6 soft pine with holes sized for the plugs.
Click to expand...

Well, doug fir at least. If you use a spade bit with the top plug diameter on one side for the inspection and the bottom (threaded) plug diameter on the other side you can paint the top of the plug with derusto paint to keep them looking good.
 
LT4247 said:
Not near Houston but,,,,,buy a few tools first. Ask around your field for a hand with the plugs. Folks be glad to help or watch youtube on subject. Tools to start:
- plug tray
- gap tool
- anti seize
- plug socket

You can never buy enough tools. :D

NOTE: Drop a spark plug on the floor and its toast!
Click to expand...
Torque Wrench
 
GlennAB1 said:
Oh, snap! There was a whole thread pertaining to torque wrenches not too long ago...
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Calibrated elbow? Hang a weight on the end of the handle to test calibration? Hit with hammer to recalibrate?

I'm kind of glad I missed that thread. Haha.

Best wished to you, @Katamarino. It's good to see pilots fiddling with their own airplanes after seeking the guidance of "professionals." Watch out for EGT probes when you remove those plugs.
 
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IMHO, the pressure "bomb" tester was a ruse to get shops to fork over $1800 of hard earned cash to Champion... Its mostly bunk...

The HFT brand pneumatic spark plug cleaner works very nicely (HFT Item #32860) for blasting the electrodes clean - $17.99
7/8" Oxgen Sensor Socket (HFT Item #69022) - $7.99
3/8" drive Click Type Torque Wrench (HFT Item# 807) - $21.99
A multimeter to check the resistance through the center electrode (Less than 5k ohms). (HFT Item# 61593) - $23.99

SPARK PLUG VIBRATOR CLEANER KIT from Spruce is pretty helpful to dig the lead out (Part #12-21355) - $23.50
TEMPEST SPARK PLUG THREAD LUBRICANT & ANTI-SEIZE COMPOUND (Part# 12-00709) - $8.25
Spark plug gapper (Part # 12-01682) - $10.95
CHAMPION CT-482 SPARK PLUG EROSION GAUGE (Part #12-00791) - $4.35
ATS SPARK PLUG GAP GAUGE (Part #12-01692) - $17.55
SPARK PLUG THREAD CHASER (Part# 12-01683) - $7.95

-YMMV! (Don't forget your 20% off coupons!)

Dana
 
NEVER buy a multi-meter at HF. they run a coupon almost every month for a FREE one with a 5 dollar purchase. :)

bob
 
Good stuff, Dana. Thanks for taking the time to list all the items.

Spark plug cleaning/rotation is coming up in about 12 Hobbs hours, so a visit to HF is in order. :)
 
unsafervguy said:
NEVER buy a multi-meter at HF. they run a coupon almost every month for a FREE one with a 5 dollar purchase. :)

bob
Click to expand...

And never use one of those low dollar cheapies without checking it against a better one for accuracy, and definitely never to do mains power work. They're not rated for it, even if they have an AC setting at those voltages.

Bad internal design with nearly no isolation between HV sections, leads/probes that'll happily cook you through their weak insulation, no proper use of safe fuses for such things, just little glass ones that'll explode and hopefully stay inside the case, when the inevitable mistake is made... etc.

All multimeters aren't designed and manufactured the same. The HF ones are complete garbage. Safe only as used for nothing bigger than a 12VDC car system, and even then, not that great.

$100 will buy a name brand instrument that won't kill you or take chunks out of your hand when you make a mistake with them.
 
thomasdr72 said:
IMHO, the pressure "bomb" tester was a ruse to get shops to fork over $1800 of hard earned cash to Champion... Its mostly bunk...
Click to expand...

That tester is very good at finding the plugs that have failing internal resistors or cracked ceramic insulators; they're the plugs that cause all sorts of rough-running headaches. There are other testers available for a lot less than Champion's.
 
Hit your dentist for an old cavity inspection probe or whatever they call it. They really work well busting out anys deeply located lead balls (from the sparkplugs that is.....)
 
Dan Thomas said:
That tester is very good at finding the plugs that have failing internal resistors or cracked ceramic insulators; they're the plugs that cause all sorts of rough-running headaches...
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Agree. I bought a well used one at an estate sale (found it buried under a pile of stuff on a workbench), refurbished it and it works really well for me.

The biggest pile of bunk imo is the Tempest promoted resistor test. I've used nothing but Champions since my first plane. First time I pulled the 24 Champion plugs on the Aztec to clean and rotate them I did the Tempest ohmmeter thing. All but two of the plugs failed. Couldn't figure out how the plane stayed in the air under that circumstance so reinstalled all of them. Engines worked fine. All but two (that the Champion tester picked out) are still in the plane after another 250+ hours.
 
The best tester you have is the engine. I very very seldom test plugs when I clean them. They were running when you removed them, if all you did was the normal clean, and set gap, Why shouldn't they run when you reinstall them?
Your going to run the engine, and do a mag check, that will tell you if you have a problem.
 
Tom-D said:
The best tester you have is the engine. I very very seldom test plugs when I clean them. They were running when you removed them, if all you did was the normal clean, and set gap, Why shouldn't they run when you reinstall them?
Your going to run the engine, and do a mag check, that will tell you if you have a problem.
Click to expand...

Hi Tom,

How many hours should the Champion REM 40E serve in the 0300 A, mine have about 270 since new and wondering if they should be replaced at annual or just cleaned?

Leo
 
Leo O'Farrell said:
Hi Tom,

How many hours should the Champion REM 40E serve in the 0300 A, mine have about 270 since new and wondering if they should be replaced at annual or just cleaned?

Leo
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Champion says 500 hours. but they blast them. which shortens the life. they should do at least 500 lean properly, keep them clean they will do the 500.
 
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