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txmike 07-26-2020 11:42 AM

Re: Spark Question

oh and also checked amp meter and it looks ok too but have not tries to jumper wire it

I have been told to do that but can someone walk me thru the process (don't laugh) as I am not a electrical guy

Jim/GA 07-26-2020 12:17 PM

Re: Spark Question


Originally Posted by txmike (Post 1913244)
ok guys - back from vacation. New Coil and new coil wire came in
I have checked all connections, all have voltage. Checked with a light and ohm meter

i get power to lower and upper plate - but the problem is it does not appear to be going to the points (Open or closed)

This is a new set of points etc; modern version with condenser up top, from NuRex

so what could the problem be. The lower plate looks fine, no corrosion etc

When checking for voltage at the points, be sure to insert a non-conductive material (a thin piece of cardboard) between the points. Then voltage will be read on the movable arm, but not on the fixed point side.

Do you have a wire between lower plate and points on upper plate?

100IH 07-26-2020 12:32 PM

Re: Spark Question

You might be better off with a simple test light- the clear plastic handle lights up when voltage goes through by way of the single wire and the "ice pick" probe. Visualization is everything. Usually works better because no numbers to evaluate - is it hot or not. Save the VOM for later. $cheap tool often under $10.00. i F BOTH TERMINALS ARE HOT ON THE AMP METER CURRENT IS PASSING THROUGH. It is possible to have an intermittent issue so wiggle it to see if the light goes on -off--on. This is called a wiggle test. it is real and worthwhile. When something passes the test - move on knowing that things are fine to that test point. Move on to the next item in the series circuit, not to the end to see of the problem went away. They rarely just go away. They might go to ground though, to make a short circuit; not getting to the end of the road, the points. The problem might also be open (a gap) where current stops flowing. The points are opening and closing - one point hot while open and then flowing to ground when closed while the coil gets a charge out of all of the flow and the condenser does too. Thinking without terms that mean something to you is useless. Read this over and over until you know what and why you are doing and in meaningful terms. The ghost of Henry Ford is looking over your shoulder, He might ask you to explain it to him. The first thing to do is draw him a wiring diagram.

Patrick L. 07-26-2020 01:43 PM

Re: Spark Question

Post #17 states there is power to open point arm. Then 0 v when closed. Thats how it should be. What happened ?

Do you have power to the points without attaching that wire to anything ? If so it seems like that wire is being grounded when attached. That can happen if not careful.

wmws 07-26-2020 02:08 PM

Re: Spark Question

[QUOTE=txmike;1913244]ok i get power to lower and upper plate - but the problem is it does not appear to be going to the points (Open or closed)

With the points open you should not have power to either plate. With the points closed the juice is going to ground through the stationary point and the upper plate. You possibly have the coil wire screwed too far into the distributor. Only screw it in about three turns.

txmike 08-01-2020 03:41 PM

Re: Spark Question

hi guys]
Back again. Sorry for intermittent posts but my battery died and I had to get a replacement. Luckily for me it was under warranty. Any way - a lot of info in the posts above and I really appreciate the help. Let me recap where I am on this thing...

1) Unscrewed cable/coil wire from the distributor - then screwed it in 3 turns
2) Using a test light and a meter on all connection
3) Power at ignition switch, terminal box, coil, and lower plate
4) Took a piece of card board, stuck it between the points - no light on test light and no reading on meter
5) This a brand new Nu-Rex set up so I doubt the condenser is bad

So what do i do from here? Read Les's manuals several times


Patrick L. 08-01-2020 05:07 PM

Re: Spark Question

Sounds like there is a problem between the lower plate and points. Connector contacting [grounding] the housing is kinda common.

txmike 08-01-2020 06:59 PM

Re: Spark Question

ok and where do i look for that?

shew01 08-01-2020 09:26 PM

Spark Question


Originally Posted by txmike (Post 1915641)
ok and where do i look for that?

There is a wire that tends to give problems.

Here is a link to a distributor diagram.

Sent from my iPhone using Tapatalk

Patrick L. 08-02-2020 05:58 AM

Re: Spark Question

#17 states you had voltage to the open point arm. Now you don't. Sounds like one of the connectors is now grounding. Look and move the one giving the trouble. Or the wire may be bad/worn and grounding.

wmws 08-02-2020 08:36 AM

Re: Spark Question

I think you can follow the path of electricity up through the distributor. The problem for someone new to model A's is seeing where that path is insulated from the body of the distributor. Those insulated places are important so the elec. doesn't go to ground at the wrong place. The only place it should go to ground is at the stationary part of the points. Study the distributor diagram in the Bratton's catalog on post 29 and you will figure it out.

txmike 08-02-2020 11:44 AM

Re: Spark Question

5 Attachment(s)
ok pictures are worth a 1000 words - so they say so look at these and comment please

rocket1 08-02-2020 11:45 AM

Re: Spark Question

TXMIKE might be in Texas,If all on the barn would put their location in there might be some one near bye that could help them,just a suggestion.

Bob C 08-02-2020 11:57 AM

Re: Spark Question

There have been problems with those wireless plates. The contacts get dirty
and they quit working. Go with the wired plates.

Patrick L. 08-02-2020 12:06 PM

Re: Spark Question

I didn't know/realize it was a wireless plate. As said they are known to be problematic. I was thinking there was a grounding issue, with that plate there may well be an open issue. I don't have a problem with the modern type upper plate as long as its a wired unit. Wire it or switch to original points.

wmws 08-02-2020 01:08 PM

Re: Spark Question

The wireless plate should work although many have reported problems with them. I don't see the connector for the wireless plate in any of the pictures.

txmike 08-02-2020 02:06 PM

Re: Spark Question

ok - will update location and order parts
back soon and


goodcar 08-02-2020 02:16 PM

Re: Spark Question

Suggest you try getting in touch with a Model A club in your area. Sounds like you could use some local hands on help with this problem.

30 Closed Cab PU 08-02-2020 02:49 PM

Re: Spark Question

I had the same type plates as those in the pictures, also had issues. One issue was an occasionally miss under low RPM/high load, Ex: going up a hill from a stop. Had other strange issues at random.

The original design has a wire to make connection from the bottom plate to the top plate, instead of the brass colored shoe/plate making the connection. The wireless plates were developed to replace the wire since the wire after a long time and a lot of flexing becomes brittle and can break. However the wireless connection moves every time you change the Retard Lever and also is purely pressure/mechanical in nature and can be a poor connection for the low primary coil points current/voltage.

For trouble shooting or if being frugal, add a wire between the 2 plates across where the wireless connection is.

Some have had issues, others have had no issues.

txmike 08-06-2020 07:43 PM

Re: Spark Question

thanks - parts came in today. I will update everyone

Note I am a member in two Model A Clubs

When I asked for help pre-COVID lots of promises to help but no one ever showed.

Now that COVID is everywhere I have not asked but may do so. I also know a guy I can pay to come over but was trying to avoid that as he is pricey

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