P-mags: Autoharness/sparkplugs or aircraft harness/plugs?

Hi.

I'm about ready to order engine, prop etc for my second -7 and I'll probably install P-mags in that engine as well.
I've dual P-mags on my first -7 and I REALLY like them.
Since the last S/B I've had no issues and Brad has been providing GREAT customer care.

I'm trying to decide which type of harness and sparkplugs to choose since P-mag offers both types.

Question for you P/E-Mag users out there:
Do you use autostyle harness + sparkplugs or aircraftstyle harness + sparkplugs?

If any of you have tried both types on your engine; what's your experiences?

My initial thoughts are that the aircraft harness and plugs are sturdier?

You may be right; the aircraft harness may be sturdier, but I opted for the auto setup and couldn't be happier. I can change out all the plugs once a year for less than the cost of one aircraft plug. Easy, cheap and no harm, no foul. The only (minor) problem is removing the adapters to check compression. The wires should last a long time.

Bob Kelly

Go full auto components. Simple, cheap, throw-away plugs and many varieties to choose from if you want to vary the characteristics. E-mag supplies top quality material. I've 300 hrs experience.

Same experience with the wires and plugs in a Lightspeed set-up. 250 hours experience.

The shield braid might make aircraft wire feel stronger, but you don't need it and the terminations are the weak point in any wiring. But a set of plugs is $160!!! Yikes! Two copper washers are the price of an auto plug! Auto plugs are $16 for 8 with an integral washer, a no-brainer.

John Siebold

More choices

I have a dual PMag set up with auto plugs and I think this is the way to go. One huge advantage is you have more choices in heat ratings of plugs. I found that the recommended plugs were too cold and were fouling out quickly. So I just switched to hotter plugs. It costs me $15. It took two tries to figure it out but now I have the perfect plug for my engine. You could not afford to do that with aircraft plugs if you could get the different heat ratings. One thing to watch though. The terminal on the auto plug screws on to the plug and I have had two unscrew and the plug wire fall off. I've started putting a very small amount of thread locker on a couple of threads (not enough to hurt the electrical connection). That has seemed to solve the problem.

700hrs with auto plugs so far and no problems (300hrs on my RV6, 400hrs on the 7A). No reason here to go for the much more expensive aviation plugs. By the way, the plug wires will be the same if you opt for aviation plugs, just the ends are different.

Martin Sutter
building and flying RV's since 1988

About the only downside

Of auto plugs is the fact you need the adaptors (which from memory are a little spendy), but of course you only need them once.

I have notice I get ignition noise with auto plugs after 50 to 100 hours, but I am told the solution is dialectric grease in the spak plug cap, so I'll be getting some this morning.

Frank

autostyle harness + sparkplugs

I wont repeat all the logic below, but I agree.

Steve Sampson said:

autostyle harness + sparkplugs

I wont repeat all the logic below, but I agree.

Click to expand...

Same for me!

Auto

Dual P/Mag's and full auto plugs/harness in my 7a.

PMAG plugs

Dual PMAGs on RV7a with 498 hours in last two years, 230 hours since PMAG service bulletin upgrade a year ago, with auto harness and plugs and I could not be happier. The plugs are $2 a piece, so I change them every 100 hours. I am very pleased with this choice.

Thanks...

Hi again.

Thanks for chiming in folks.

All your comments makes sense and since you all agree on autostyle, that's what "Kermit" (the name of the RV) will have for his dual P-Mags then.

Copper washers

RV7ator said:

Two copper washers are the price of an auto plug! Auto plugs are $16 for 8 with an integral washer, a no-brainer.

John Siebold

Click to expand...

For you guys with aircraft plugs, hang the washers on a piece of safety wire and heat them with a torch. When you get them very red drop them in some water. That anneals them and they get soft again. That's backwards from steel. You can re-use them practically forever.

Old A&P trick.

Don