Author Topic: Help Needed - Spark Plug Question  (Read 6295 times)

Offline b.lindsey

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Help Needed - Spark Plug Question
« on: April 07, 2013, 06:17:11 PM »
I have been getting the Briggs engine ready for Cabin Fever and am having an issue I think with the spark plug.  When i connect the plug and ground it against the head I am getting a strong and normal spark at the gap.  But....when I install the plug in the head and connect it, I am getting arcing between the connector and the hex part of the plug external to the cylinder. Is this a breakdown in the ceramic insulator??  The plug was one I had gotten from Bob Shores a few years ago and had been working fine though I have noticed this arcing more recently on an intermittent basis.  When I check with an ohmeter I am getting 2.2 ohms when measured between the plug connector and the base where it screws in. This should be more like infinite resistance shouldn't it?  Any help here appreciated. I may have to wait untili I get to  Cabin Fever to get a new plug due to the short timeframe.

Bill

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Re: Help Needed - Spark Plug Question
« Reply #1 on: April 07, 2013, 06:23:25 PM »
I think your on to it Bill....I guess you don't have another plug to try?....

In any case....try backing off the plug tightening torque and see if it comes back...might prove it is the plug...
Good luck bud!

Dave
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Damned ijjit!

Offline b.lindsey

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Re: Help Needed - Spark Plug Question
« Reply #2 on: April 07, 2013, 06:26:57 PM »
Unfortunately I don't have another to try Dave, but I will try backing off on the torque and see if that helps any. Not good timing for sure...no pun intended.

Bill

Offline ScroungerLee

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Re: Help Needed - Spark Plug Question
« Reply #3 on: April 07, 2013, 06:31:54 PM »
There is a possibility that if you clean the outside of the ceramic insulator well you might solve your problem.  Plugs can get a track of carbon on the ceramic that allows arcing.  More likely the insulator is cracked though, sorry.

Lee
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Offline b.lindsey

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Re: Help Needed - Spark Plug Question
« Reply #4 on: April 07, 2013, 06:50:27 PM »
Thanks Lee,  I have tried cleaning it outside and on the underside too to no avail. As Zee would say....DRATS!!! Thanks for the reply though.

Bil

Offline zeeprogrammer

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Re: Help Needed - Spark Plug Question
« Reply #5 on: April 08, 2013, 10:26:27 PM »
As Zee would say....DRATS!!!

I've got more if it would help. Never helped me.

[EDIT:] P.S. The word would be 'drat'. I do one drat at a time.  ;D It may be followed by more drats...as in 'drat drat and drat'...but never drats. A boo-boo deserves the time it takes to curse it.
« Last Edit: April 08, 2013, 10:56:45 PM by zeeprogrammer »
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Zee-Another Thread Trasher.

Offline b.lindsey

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Re: Help Needed - Spark Plug Question
« Reply #6 on: April 09, 2013, 01:12:25 AM »
Thanks Zee but I doubt it would help also. I talked to Roy Sholl @ cncengines this morning and have 2  VR2 plugs and a spare Hall Sensor coming via express mail so should be here in plenty of time. The bad news is that because of the close dates of CF and NAMES, he won't be at Cabin Fever :(  Was looking forward to meeting him.

Bill

Offline Don1966

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Re: Help Needed - Spark Plug Question
« Reply #7 on: April 09, 2013, 01:23:39 AM »
You are correct Bill you should read infinite from the tip to the base. And a broken plug ceramic insulator will cause you big problems, it's best to replace it.

Don

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Re: Help Needed - Spark Plug Question
« Reply #8 on: April 09, 2013, 01:32:00 AM »
Hey Bill,

How about making one up for yourself?   I know plugs made with corian work pretty well....Steve Huck uses them on his V8...and I know my friend Rollie uses them on his Bently BR2.    Got nothing to lose but some time in the shop....you can get a small piece as a sample square from anyplace that makes corian counter tops   They are about 1" square and 1/2" thick with rounded corners....show them what your doing, and I'm sure they'll give you what ever you need.

Just a thought....I just would love to get you back up running again bud!
Dave
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Damned ijjit!

Offline cheepo45

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Re: Help Needed - Spark Plug Question
« Reply #9 on: April 09, 2013, 01:47:51 AM »
I have made several plugs with Corian insulators and they worked fine. I used 5/16" hex stock for the shells and 1/16" welding rod for the center conductor. Check with me at Cabin Fever-I have some samples.
             cheepo45

Offline Bearcar1

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Re: Help Needed - Spark Plug Question
« Reply #10 on: April 13, 2013, 04:03:20 PM »
I hope you get your plug issues sorted out without a great deal of hassle Bill, and have your exquisite B/S engine running fine for the show. If I were attending the show I would most certainly donate a plug to you for a chance to see the engine up close and personal. Best of luck


cheers


BC1
Jim

Offline Tennessee Whiskey

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Re: Help Needed - Spark Plug Question
« Reply #11 on: April 13, 2013, 05:00:51 PM »
Fellas, he did indeed get the problem sorted. I just physically saw it run. Sweeeet :ThumbsUp:

Eric

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Re: Help Needed - Spark Plug Question
« Reply #12 on: April 13, 2013, 07:45:00 PM »
A rather good article here if you fancy making your own

http://modelengineeringwebsite.com/Miniature_spark_plugs.html


John

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Re: Help Needed - Spark Plug Question
« Reply #13 on: April 13, 2013, 10:53:13 PM »
YUP....Corian works well too.....same deal

I've seen the Corian loctited in also...still worked.

Dave
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Damned ijjit!

Offline stevehuckss396

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Re: Help Needed - Spark Plug Question
« Reply #14 on: April 13, 2013, 11:33:02 PM »
I just finished making up 5 sets today. Corian is what I prefer. It machines well but it does require some care. It will snap easy. I will be at NAMES next week making insulators on a CNC sherline lathe.



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