Topic: Cross fire


GORDON    -- 10-28-2011 @ 11:50 AM
  Hi, Took the Pilot out for a run after fitting n.o.s distributor and cap, and new h.t cables.In the past I had run one cable outside the conduit. It was on the right hand side, plugs 5-8.I now have a miss this side ,and I cant remember what cable it was,any idears?Also if I can hit 80mph ,I assume all is well ,at the moment it is 70.mph.Is this a good test ,Flat road, 3.9 cc 24 stud engine 3 speed standard Pilot diff .PS Pilot is like a 38 .Thanks for your help Gordon.


TomO    -- 10-29-2011 @ 8:53 AM
  Gordon,

The driver's side (right hand drive) is numbered 1-4 for the spark plugs on the US engines and the passenger side is 5-8. I though that the Pilot used the same numbering system.

If you used the incorrect numbers for installing the wires, this could account for your miss.

Tom


fomocoloco    -- 10-29-2011 @ 8:43 PM
  Lets see a picture of your Pilot, please.

weezer


GORDON    -- 10-30-2011 @ 2:22 PM
  Hi, yes you are right Tomo 5 to 8 is the passanger side ,I will take out one wire at at a time ,I will start with no 7 as I think that was the one out side in the first place, I am sure thay are wired correct.I am not sure how to do pictures,I think there was a British service bullitin about this cross fire,but I might be imagining it.Cheers Gordon


Stroker    -- 10-30-2011 @ 3:28 PM
  Gordon:

You may be correct regarding the bulletin re the "outside plug wire. On most V8's, the center two cylinders on the right bank fire only 90 degrees apart. The thinking was that having those two wires bundled closely in parallel could cause a high speed miss due to induction from one to the other.

In the 50's, most OHV's would cross those two wires from the factory, rather than allowing them to be routed in close proximity in parallel. By sparking both plugs simultaneously due to the aforementioned induction, the coil simply didn't have enough saturation time to recover and fire number 3 the second time in less than 90 degrees at high speed.

Most of my "high speed" flathead experience, and later OHV performance work involved keeping the wires separated with rubber spacers, and isolating these sequential firing adjacent wires, so that they were
not running parallel along their length.

This message was edited by Stroker on 10-30-11 @ 3:34 PM


TomO    -- 11-01-2011 @ 7:26 AM
  Gordon,

Doing photos on this site is easy. You must have the photo in your computer.

When you are replying to a topic or starting a new topic, you will see a box that says "Choose File". Click on the box and then open the the photo file. You can only post 1 photo per reply this way. To post multiple photos, read the sticky post at the beginning of General Ford Discussion.

Tom


fomocoloco    -- 11-01-2011 @ 10:21 AM
  i dont see "choose file".

weezer


TomO    -- 11-02-2011 @ 8:11 AM
  It is right next to IMAGE ATTACHMENT. Scroll down to see it right under the reply box and above Submit Reply

Tom


fomocoloco    -- 11-02-2011 @ 10:33 AM
  i see preview, submit reply, image attachment, browse, and thats it. no choose file. im new at this, but not blind. maybe i should contact the webmaster.

weezer


GORDON    -- 11-05-2011 @ 3:30 AM
  Hi, Back to the cross fire ,Chris our local president has just sent me the 1950 service bulletin .if Pilot is missing or loss of power ,remove leads 8 and 4 ,and put them in oposite conduits ,crossing and double insulating when returned to correct plug at back of engine,I must have been to lazy to do this and just run them outside .Thanks Chris, and every body who took an interest Cheers Gordon.


supereal    -- 11-05-2011 @ 8:49 PM
  Cross firing isn't uncommon in the metal sparkplug wire conduits, particularly if the wires are old. The insulation develops small cracks, and any moisture present aids the leakage. New, metal core plug wires will usually cure the problem. Be sure to solder the end fittings, as a poor connection can cause a voltage buildup in the wire as it seeks ground.


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