Timing, Timing Light Question

41woodie · September 21, 2012, 10:12:05 AM

I use a dial-in timing light to set the timing on the SBC in the Woodie. I crank in the initial timing number and adjust the distributor until the mark hits 0. My question is that there is a random flash of the timing light that appears approximately 10 degrees from 0. I seem to remember seeing it on several different engines over the years.
The distributor is a good quality HEI purchased new, I'm using Jacobs silicon wires, the engine runs like a champ. No apparent miss, great throttle response etc. etc. The engine has about 1400 miles on it.
Am I seeing spark arcing in the distributor or what, any thoughts.

wayne petty · September 21, 2012, 01:00:48 PM

yes... you are seeing a second wire flashing usually..

you may want to verify that you have enough space between the wires so the corona/magnetic field that is created by the high voltage spark going down the wire from INDUCING a ghost spark in another wire...

try timing it off the #6 spark plug wire..

thats the second turn of the crank...

1843
6572

please remove the tie wraps that hold the wires together in a bundle.. not saying that they are there... i have seen many cars and trucks with the wires bound together..

this really effects the last 2 cylinders in the left side as they fire 90 degrees of crank rotation apart.. the #5 spark will induce a spark in the number 7 wire and cause the partially compressed fuel mixture to ignite burn some of it off and cause the cylinder to run very lean... put some load on the engine and that piston will MELT and tear up the cylinder wall...

look at what ford did with its small block spark plug wires...

there are several more places this could be an issue...

if your inductive clamp is too close to another spark plug wire.. it can create a out of phase flash...

if your reluctor is cracked... or the pick up coil magnet is cracked...

if one has a Small cap HEI on a TBI motor.. look carefully for cracks... find reman usually from cardone.. with a reluctor like this...

if you have a digital volt meter.. that has a 200K Ohm setting.. not just 200 which is the lowest setting on many..

200K OHMs... 200,000 ohms..

measure your spark plug wires from the terminal inside the boot at the spark plug end... to the inside terminal of the distributer cap...

max resistance is 1,000 ohms per inch...

on the volt meter at this 200K setting.. a 24" spark plug wire will read between 9 and 15.. on the display... if it reads more than 24.. its bad.. if it reads close to 24 its bad..

an 18 inch wire will read less than 18... 7 to 15 on the display...

could be the terminal at the cap is not pushed down.. could be the terminal is pulled off at the spark plug wire end.. this happens a log..

please examine the exterior of the coil for signs of high voltage leaks....

this is what happens when the folded metal ground strap is left out of the big cap HEI distributers... or the screw that holds the condenser down is left loose...

makes a noise like shot gun going off under the hood..

sorry for the long post....

41woodie · September 21, 2012, 09:09:44 PM

Wayne when I posted my question I had two hopes, one was that you would respond with one of your usual insightful and detailed responses and second that I would be smart enough to understand your response.

I probably need to fill in a few details, I'm running a large style, coil in cap HEI distributor. I'm pretty obsessive about plug wire routing and I'm using Made for You separators, in fact I'm using two sets of them to make sure the wires don't cross or touch.

The timing light is an induction type and it's possible I'm getting my phantom spark from it's being too close to another wire. I'll recheck the timing, making sure that the pickup is well away from other wires. I'll check out the cap and internals for signs of tracking or damage.

I'm in the process of buying a Simpson 260 VOM so I can do accurate testing of the circuit. If I don't find any visible defects or eliminate the problem by isolating the pickup I'll do the tests that you recommend and see what that tells me.

One thing I'm unsure about is your suggestion of checking the timing of number 6, I'm assuming that number 6 will also show the timing mark at 0 but be 360 degrees from number one. Or am I all wet. Many thanks MH

Quote from: "wayne petty"yes... you are seeing a second wire flashing usually..

you may want to verify that you have enough space between the wires so the corona/magnetic field that is created by the high voltage spark going down the wire from INDUCING a ghost spark in another wire...

try timing it off the #6 spark plug wire..

thats the second turn of the crank...

1843
6572

please remove the tie wraps that hold the wires together in a bundle.. not saying that they are there... i have seen many cars and trucks with the wires bound together..

this really effects the last 2 cylinders in the left side as they fire 90 degrees of crank rotation apart.. the #5 spark will induce a spark in the number 7 wire and cause the partially compressed fuel mixture to ignite burn some of it off and cause the cylinder to run very lean... put some load on the engine and that piston will MELT and tear up the cylinder wall...

look at what ford did with its small block spark plug wires...

there are several more places this could be an issue...

if your inductive clamp is too close to another spark plug wire.. it can create a out of phase flash...

if your reluctor is cracked... or the pick up coil magnet is cracked...

if one has a Small cap HEI on a TBI motor.. look carefully for cracks... find reman usually from cardone.. with a reluctor like this...

if you have a digital volt meter.. that has a 200K Ohm setting.. not just 200 which is the lowest setting on many..

200K OHMs... 200,000 ohms..

measure your spark plug wires from the terminal inside the boot at the spark plug end... to the inside terminal of the distributer cap...

max resistance is 1,000 ohms per inch...

on the volt meter at this 200K setting.. a 24" spark plug wire will read between 9 and 15.. on the display... if it reads more than 24.. its bad.. if it reads close to 24 its bad..

an 18 inch wire will read less than 18... 7 to 15 on the display...

could be the terminal at the cap is not pushed down.. could be the terminal is pulled off at the spark plug wire end.. this happens a log..

please examine the exterior of the coil for signs of high voltage leaks....

this is what happens when the folded metal ground strap is left out of the big cap HEI distributers... or the screw that holds the condenser down is left loose...

makes a noise like shot gun going off under the hood..

sorry for the long post....

wayne petty · September 21, 2012, 09:36:35 PM

instead of buying a simpson 260... i have one i have never plugged the new test leads i got in ...

why not drop 20 bucks and get a decent cheep HF digital volt meter...

i have one of these... i use it a LOT...

http://www.harborfreight.com/ac-dc-digital-multimeter-37772.html

it is not as annoying as the 99 buck innova blue meter that beeps and shuts off if you don't quit turning the knob every minute or two....

its not as tough as the innova or the OTC megameter that i bought 20 years ago for a hundred and fifty bucks... but its only 20 bucks.. so when i quits... its trash and i grab another new one...

HF also sells this automotive version... that i have been thinking about...

http://www.harborfreight.com/lcd-automotive-multimeter-with-tachometer-kit-95670.html

but i does not have the cool tilt up display that i use a lot when wedged under a dash... so i can see the display at poor angles...

one thing to make these meters really really really handy...

proper piercing test clips..

i pick up test lead wire and make my own set of them that have 7 foot of wire on each side... tied at the stackable bananas... tiny ring terminals at the clip ends... this makes them easily repairable...

rooster got a set of these... i wonder how he likes them..

41woodie · September 21, 2012, 10:02:45 PM

Heck if Harbor Freight VOMs are good enough for Super Wayne, it's certainly good enough for me, thanks for the link. Where did you get the piercing leads, I've never seen a set of those.
I laughed out loud about the using your VOM under the dash, when I did my rewire on the Woodie I could read the meter better upside down than right side up. I desperately need a set of upside down bifocals for underdash work.

wayne petty · September 21, 2012, 10:45:37 PM

Quote from: "41woodie"Heck if Harbor Freight VOMs are good enough for Super Wayne, it's certainly good enough for me, thanks for the link. Where did you get the piercing leads, I've never seen a set of those.
I laughed out loud about the using your VOM under the dash, when I did my rewire on the Woodie I could read the meter better upside down than right side up. I desperately need a set of upside down bifocals for underdash work.

this is a set that i make up from local parts... i am out of the test clips... do you have any serious electronic parts stores near you...

the clips are telecom angled nose test clips...
like these

http://www.newark.com/catalog_129/index.html?page=2247
you will probably want the $4.10 version and the $5.00 buck version on the upper right of the page above..

there were some laying next to my desk... but they have vanished... i don't know where they went and am afraid to ask.. there was a surplus store down in florida.. that sold cut off pairs for 7 bucks.. these are used for telephone communications.. and usually come attached with tinsel wire.. thats too thin to get any kind of voltage reading .. its just for audio signals...

the bananas are pomona stackable bananas..
http://www.newark.com/pomona/1825-0/banana-plug-15a-screw-black/dp/30F1400?in_merch=true&MER=ALT_N_L5_Connectors_None

the wire is 17 or 19 gauge test lead wire ..

what's worst.. i used to be able to walk into radio shacks and buy all the parts.. not any more..

you will still need to find test lead wire.. as its special... and my local electronics store has folded after 50 years of operation.. too much competition from cheep audio stores..

wayne petty · September 21, 2012, 10:57:15 PM

say... 41 woodie... can you log in.. check your profile..

see if you have any GIF or images loaded that normally show up by your name...

there might be a problem there that is slowing the loading of this page down... you might want to delete any links or gifs to see if the post loads at a normal almost instant speed...

i see one with this title that does not load...

http ://www.members.cox.net/mike.higbee/Woodie jpg

i separated the words to prevent it from attempting to load..

or am i the only one having this issue...

41woodie · September 22, 2012, 12:07:20 AM

Wayne I noticed that the page was loading super slow I just thought it was because of the number of images. I noticed earlier that my avatar wasn't being displayed and just remembered that the server, Cox.net, where the image was stored has been taken down several months ago. On my profile I don't see any mention of the cox.net...woodie.jpg image you referred to. As it is no longer a valid URL I would remove it but don't see where to remove it from. Do I need to contact one of the admins and ask if they can remove it from my profile. If I didn't say it before, your assistance is greatly appreciated. Mike H. -- 41woodie

wayne petty · September 22, 2012, 12:27:03 AM

Quote from: "41woodie"Wayne I noticed that the page was loading super slow I just thought it was because of the number of images. I noticed earlier that my avatar wasn't being displayed and just remembered that the server, Cox.net, where the image was stored has been taken down several months ago. On my profile I don't see any mention of the cox.net...woodie.jpg image you referred to. As it is no longer a valid URL I would remove it but don't see where to remove it from. Do I need to contact one of the admins and ask if they can remove it from my profile. If I didn't say it before, your assistance is greatly appreciated. Mike H. -- 41woodie

yes... they will be able to help....

its at the bottom of the profile page when you are logged in..

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41woodie · September 22, 2012, 10:14:11 AM

Wayne, I opened my profile and didn't see any entries in the various blanks for avatars. I did check the delete images box and hit save. The thread page seems to be loading almost immediately so perhaps it was retaining a link, I'm slightly less computer savvy than I am car savvy so I'm really not properly equipped to discuss the problem. Hopefully it'll stay fixed.
Now to get back to the errant spark problem and see if I can find a ''remove errant spark'' box to check. MH