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Show us your spark plug wrench -please

H

humptybump

Well Known Member
Im into my second condition inspection and have now tried a few different options for pulling (and installing all of the plugs). All attempts have been sub-optimal - especially on the top plugs (at least one is proving impossible) while attempting to use a torche wrench during installation.

My deepest socket does not allow for the torche wrench to fit on. My shallower sockets wont catch the faces of the plug. My open ended wrench does not fit. My box end wrench hits the fins.

What tool, trick, or fabrication have you found to work? Pictures welcome !

BTW: in my case, the plugs have the wrench point at the base, just above the threads (worse case scenario).
 
Removed...


Never mind I reread your post it's about torquing the plugs... I don't use torque wrench on plugs. Snug then turn half a flat :D
 
Usually not a problem

A deep socket with a 6 inch extension should work fine. I'm not sure why you are having problems. Maybe you can post a pic of your installation.
 
I use a Craftsman deep socket, you just have to find one where the hex (or 12) flats go all the way down the socket - which might rule out the Harbor Freight cheapies...:)

I then trimmed some of the end of the socket - perhaps 1/8 to a 1/4 inch - to make it as low profile as possible to fit by the upper baffles.
 
What Gil said-------many sockets will not fit over the metal shell of an aviation spark plug, where they will work just fine on almost any thing else. Too small inner bore in the socket.

I took a spark plug to the hardware store, and checked out various sockets until I found one that would work for me.

Sorry, dont have the brand name handy right now, but I got it at a True Value store.
 
I( did the same as Mike. I took a plug to the local Lowe's Aviation supply store and found a deep socket that worked. It is actually a black impact socket with a 1/2" drive. So I also purchased a 1/2" - 3/8" adapter. No problem with it and my torque wrench and baffles on my RV-4.
 
My 3/8 drive S-K deep socket with an extension works. My Craftsman and very expensive Champion do not work.
 
I found a cheap harbor freight deep socket that does the trick nicely with my REM40E's. Granted, I don't have any baffling installed yet so I don't know if that will create any additional restrictions. I'll try to post a pic tonight.
 
I use a torque wrench on the bottom plugs but the baffles don't allow room for that on the top plugs. I do the top plugs by feel, using the bottom plugs as a reference.

I like the $nap-on socket, pretty sure it's this one:
http://buy1.snapon.com/catalog/item...roup_ID=675512&store=snapon-store&dir=catalog

It's shorter than some, but still engages the plugs fully. The spring retainer works well. The magnetic socket I tried was too long- it didn't even fit on the top plugs with a breaker bar, let alone a ratchet or torque wrench.
 
I forgot to mention the deep Craftsman socket I modified was 1/2 drive.

For the inaccessible #4 cylinder, I use one of these and a hex wrench -

LIS57560.jpg


http://www.sears.com/shc/s/p_10153_12605_SP101A10877S4581216901P
 
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I have a plain old 7/8" craftsman box wrench that I heated up with a torch to get slightly more bend in the closed end. That along with my calibrated arm have worked fine for years.
 
I think Gil has the answer I am going to try.

I found a suitable deep socket that I can get onto my Autolite/Unison Aviation REM40E plugs. However, for #4 I can not then get a socket or torque wrench onto the end because the baffle wall. (There is no way I could get the ATS MAGNETIC SPARK PLUG SOCKET to fit any of the top plugs.)

I had looked for a deep socket that also had exterior flats on the wrench end but could not find one that was deep enough.
 
humptybump said:
I think Gil has the answer I am going to try.

I found a suitable deep socket that I can get onto my Autolite/Unison Aviation REM40E plugs. <snip>
Click to expand...

I suspected you were using Unison plugs... FWIW, I had the same problem on my -8 when I changed to Unison plugs (wrench baffle interference on top plugs). The Champion plugs are shorter than Unison, and switching will (most likely) solve your dilemma.
 
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During my current Condition inspection, it was decided my beloved finewire plugs might not make another year. I scored a good deal on the Unison plugs more than a year ago so they have been lying in wait.

I'll watch for a deal on Champion plugs. At my current rate of flying, I'll need new plugs in about 7 years :)
 
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You have a couple of choices

You could remove or loosen your baffles enough to get the torque wrench in there
Or, you could get the 7/8 in socket with the flats for a regular wrench. Then the appropriate size crow foot wrench to put on the torque wrench, calculate for the extension length and torque accordingly. (if you can put the crow foot on at 90 degrees to the torque wrench you won't even need to do a calculation!)
Then there's also the calibrated arm method which has served many people well for years. Although, I will say, some people think tighter is better and I have seen things tightened way too tight, which could easily break a plug.
Good luck.
 
I have a torque wrench with a 3/8" drive. Aircraft spruce sells a 3/8" drive spark plug socket (non magnetic version) these two play happily for me.

Slip the socket over the plug, then snap the torque wrench on the back, there is sufficient room between the baffles and socket to do this. The plugs should be installed most of the way with your fingers only.
 
avery tools

I bought a socket from Avery tools that is designed so that you can put a box wrench or crescent at the top for tight spots. Works great but a little expensive.
 
Thanks to all of the comments and descriptions to the thread, I ventured into the shop and machined up a suitable spark plug socket.

I started with a Craftsman deep impact socket since it was deep enough for my Unison plugs. It actually was more than deep enough so I machined off a little from the open end. I then machined the socket end to accept a 1" open ended wrench.

I suspect I could find a pre-made version of this solution if I didn't live in farm country where everything is a 90 minute drive or more.

 
I thought Unison plugs were shorter, but I need to look again.

What is different is where the hex portion is relative to the base of the plug:

Champion

CH_REM40ESm.jpg


Unison

unisonspkplug.jpg


This affects how deep your deep socket needs to be...:)
 
az_gila said:
I thought Unison plugs were shorter, but I need to look again.

What is different is where the hex portion is relative to the base of the plug:

Champion

CH_REM40ESm.jpg


Unison

unisonspkplug.jpg


This affects how deep your deep socket needs to be...:)
Click to expand...

I complained to Unison at Oshkosh about this........ and they handed (gave) me a socket that works great.

Then I switched to auto plugs on the top.
 
Gil - when I pulled the old plugs, one was the champion design. Fortunately, when I went shopping for a socket, I had one of my new Unison plugs so I shopped for the deeper socket with flats all the way up the inside.
 
az_gila said:
I thought Unison plugs were shorter, but I need to look again.

What is different is where the hex portion is relative to the base of the plug:
Click to expand...


Gil, you are absolutely correct and I apologize for the misinformation. My memory just isn't what it used to be. :)
 
ccsmith51 said:
Are Tempest plugs more like Champion or Unison regarding where the flats are?
Click to expand...

Tempest is the company that purchased the plugs Unison sold.

tempestplugs.jpg


The photo I found online look just like the Unison. Will have to look at the new ones that I purchased at OSH.
 
Special Delivery said:
Gil, you are absolutely correct and I apologize for the misinformation. My memory just isn't what it used to be. :)
Click to expand...

And I thought it was my memory failing...:)

I vaguely recall buying a new set of Unison plugs just becuase they were shorter, and then cutting down my deep socket for a precise fit on the new plugs.

This has prevented banged up baffles ever since...
 
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