Fine-wire spark plug maintenance???

[flyboy1963]

Just bought a set at a swap meet ( thanks Ken!)

the plug electrodes are in good shape, but a little rust around the insulator.

Opinions vary on maintenance.... some say never touch them, and here's a tech sheet that says to sandblast them like the massive electrode!

http://www.tpub.com/content/operatormanuals/TM-9-4910-422-12/TM-9-4910-422-120026.htm

I can see that the fine wires are subject to damage, but I could cause as much digging around in there by hand, as a quick blast of grit.

What about gapping? ( .016 - .021 on the box)
I don't have the fancy tool, so what's the 'homebuilders' secret? wooden chopsticks?

 

[Mel]

DO NOT sandblast fine wire plugs!

We had a guy sandblast a set of fine wire plugs on his C-182 during an annual inspection. He ALMOST made it home!

 

[flickroll]

As Mel mentioned, DO NOT SANDBLAST fine wire plugs. Use a dental pick to clean any lead deposits, crud, etc. off the insulator. Check the gap, lube the threads, and reinstall. That's it.

 

[turbo]

i have had

mine in for 550 hrs and all i do is rotate them on annual and pick a few crumbs out of them. love em. they will go to tbo for sure. no wear yet. turbo

 

[F1 Rocket]

What happens if you sandblast them?

Danny

 

[Bob Axsom]

Well - one man's experience ...

Not knowing any better I "sand" blasted mine and have noticed no difference - but I'm considering not doing it again after reading this thread. However, I adjusted the gap and the very brittle platinum electrode broke on one of my $76 (as I recall) plugs. I used the fine wire adjusting tool from ACS to bend the side electrode. I called the company and the tech support specialist said never try to change the gap on them. He said you can get away with one slight adjustment in one direction if they are out of spec but the second tweak back will often break the electrode it as it did in my case.

Bob Axsom

 

[petercavallo]

Gapping fine wire plugs

My experience is just check the gap, if you try to regap the Pt or Ir electrode often breaks off.
I have had good success with taking the lead goobers out gently with my dental pick (just ask your dentist they usually are happy to give you a couple of the old ones)
clean the threads test and reinstall.

Peter

 

[flyboy1963]

the fine line

hey thanks eveyone...I'll avoid blasting them if or until it's a last resort, and as the gap is .016 - .021, I wont' be touching the electrodes, for fear of breaking the little buggers.
I had hoped to gap them for my still-in-the-box electronic ignition, where much larger gaps are the norm...but is this necessary, or desireable?

anyone running electronic with them?

 

[Bob Axsom]

LASAR is Electronic with a mag backup mode

I ran for a few years on massive electode Champion plugs then a couple of years ago I switched to the Autolite (I think that is correct - they are the ones that were from Unison - I think ownership has changed now). After I changed I did my normal 6,000 ft density altitude triangular course speed test and the speed was slightly higher but close enough to be within the test method error margin. So - inconclusive. I run my engine fast all the time and I have had no lead fowling problems at all. The lower plugs were slightly wet when I pulled them in the annual condition inspection several weeks ago. I blasted them with the black abrasive material from ACS and they all cleaned up nicely and I installed them 1 to 2 and 3 to 4 top to bottom and vise versa. I checked the gaps to verify they were in the specified range and found one was too tight. I ran a wedge between the center electrode and the side oriented outer (ground) probe to open it slightly - I may have used a tapered ice cream stick or a very small common screw driver - not sure. A few years ago I ran a comparitive speed test with my massive electrode plugs set at the maximum and minimum gap specs. I could find no difference in speed - I really don't care a lot about anything else other than reliability. My conclusion is spark plugs are more of a facilitator than performance enhancer based on my own testing. It just doesn't seem to be a parameter to waste a lot of time on.

Bob Axsom

 

[Dan92]

Where is it written that the fine wire iridium plugs cannot be blasted? I looked in Champions Aviation Service Manual AV6-R on championaerospace.com and cannot find a warning not to blast the plugs with their CT-475 cleaner/tester. Maybe I missed something. The only warning I can find is to be careful when you adjust the gap. Maybe some people are using the wrong blast medium.

Dan

 

[flyboy1963]

MOre info muddies the water

hmmm....more Googling has come up with lots of Champion and other manufacturers clearly showing equipment and instructions to blast fine wire plugs, even a 'cutter' head for the Vibrator unit to clean heavy lead deposits!

I'm also curious about gapping, if touching the fine wires leads to breakage, how do you grab them exactly?
The Champion tool has a gauge, but what the heck are these 'slots' to allow 'easy adjustment' of the gap?
try to post a pic here.......dang, never works!!!

seems most gapping tools are for closing the gap, not opening.

 

[rv9av8tr]

Blast cleaning fine-wire plugs

We had a guy sandblast a set of fine wire plugs on his C-182 during an annual inspection. He ALMOST made it home!

That's interesting.... I blasted the fine wire Iridium plugs in my Long-EZ for 900 hrs of operation and never had any trouble. Yes.... 900 hrs on the same set of plugs! Have to be very careful about any grit left inside the plug cavity.

 

[turbo]

i have had.........

good results with the fine wire plugs. these have 550 hrs and look like new. easy to clean with dental pick. no gapping yet.