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My old reliable Ford has finally stumped me! It has got no spark in the system and here is what I have done so far:

new points & condenser (Nu-Rex plate w/ newm1970's V8 Ford parts)

point gap= .019"

new coil- bench test 1.3 ohms across terminals, 8,530 ohms across terminal to high output center

re-timed (a few times now!)

6.4V at each coil terminal and at arm of points with switch on and points open

plugs cleaned and gapped to .035"

checked pigtail from upper plate to lower plate for shorts

no spark jump from coil lead to block or from brass strip to block when cranking. Also no spark snap when closed points are broken.

car cranks strong, lights are bright

can flood it and smell gas when cranked with plugs out so i think it is getting fuel.

All I can think to try next is test the switch. It is the new thin cable type, not the original pop out but has been very reliable for 10+ years (like the points/condenser setup).

Any ideas or tests I have missed? This car has been our favorite tour car for years because it is so reliable but she has me stumped at the moment.

Thanks- Bill

On Ahooga I read a thread about a battery condition where it could crank or spark but not both. New battery, problem fixed! But I on't think that applies here as I get no spark.

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I think it is your ignition switch, unless you have a fuse and it is blown.

Here is the preliminary test sequence that I recommend (from Les Andrews' Book).

1 Test for 6 volts at battery connection on starter (check both sides of the fuse if you have a fuse)

2. Test for 6 volts on both terminal box wing nuts.

3. Test for 6 volts at both coil terminals

4. Place a piece of paper between the point contacts in the distributer to keep points open.

5. Turn ON ignition switch and test for 6 volts on teh open point arm.

This test has checked all wiring connections from the battery to the points. If any of the Preliminary Test failed, trace the fault to a disconnected or broken wire in the circuit.

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You can buy a little tester in Bratton's catalog. it has two red lights. the upper one comes on if all is well with the points, condenser and coil.the lower light comes on if the primary coil wires are reversed(the red wire should be on the passenger side). no light comes on if there is a problem but at least you know it is upstream.

Edited by Dave Mellor NJ (see edit history)
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Thanks for the input guys!

Matt- I do not have a fuse in line. That is the procedure I followed per the book.

Dave- I saw this toy in Bratton's last nite, wondered how well it worked. I have Bratton's with me today and was going to order a new switch at lunch. Maybe I will get this tool too.

Again, thanks!- Bill

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Matt- I had 6.4 at all points- battery, term box, coil, points arm. That is why I am stumped. Everything says I should have spark.

I ordered a new switch and cable at lunch as well as a backup coil from Bratton. They may be here by the weekend but probably Monday.

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If you have voltage at all of those points, then the switch is OK. The problem is either fuel related or timing related. Perhaps the timing gear wore out and it jumped a tooth or two? Check the timing gear. If it is OK, I think that you have a fuel problem.

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I just re-read your earlier post. If the switch is on and the points are closed, opening the points you do not see a spark, then something is wrong somewhere sounds like something is shorted or maybe either your new coil or new condensor is not any good? The troubleshooting chart in Les Andrew's book has never failed me.

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Thanks Matt, I will do all those things.

I do not really think it is the switch either as I have voltage at the breaker arm. I believe any disconnect(break) thru the switch/cable would prevent current at the arm.

All data I have found for bench testing the coil says all three coils are out of spec and no good. However none of it is Model A specific numbers and I can only get generic, one size fits all 6V coils. Even the new generic one from Bratton is not spec'ed for A's apparently.

As for timing I have timed it a few times now and thought about maybe it jumped timing. However when the pin drops in the recess the piston is at TDC (I always pull #1 plug and check by reaching in with a screwdriver to feel for it.) And I feel compression as I come up on the recess when hand cranking so I am guessing the valves are closed properly.

I also smell gas (strongly) when cranking with the starter and a couple of plugs out so I feel it is getting fuel.

Like I said I am stumped. I will go do the reading homework you suggest and see where it leads me.

Thanks- Bill

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Hey Matt I bought some parts from Bratton on Thurs afternoon and the FedEx truck showed up at 10:30 this AM! Very good service by all IMHO! I finally got to play with it this PM and she is running again!!!!

The bad part is that I do know what I did to fix things. I was going over things again and reread the book, specially the part about "no snap" at the points meaning a bad condenser or very bad point contact. Soooooo, even though they are new points, I took a fine stone and dressed the faces of the points. I immediately noticed a snap when I broke the points. I put things back together, pushed the button and she lives!

All I can think is that there was a coating on the points- to prevent corrosion or something and a little stone work cleaned them off. Needless to say I am a happy camper!! Now I can move on to other work (adjusting the brakes, new tires, etc) as I get the car ready for the Glidden in Sept. But then we had another conversation this evening about taking the '13 Stude instead....

Thank to all for all your help - Bill

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If you watch the rotor turning as you crank it and it stops at the #1 cylinder when the pin slips into the hole, the timing gear and also the cam shaft and ditributor shaft are ok.make sure the contact point in the dist cap is good.It should protrude down 1/8" or so. that tester should tellyou that.Also, make sure there isn't excess play in the dist shaft.

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Actually Dave one of the things I got was a new cap and I noticed the 'button' on the inside was much taller than the old cap. It was at least an 1/8" taller, domed rather than flat, etc. I used the new one with a new rotor and distributor body. Just figured the old girl deserved the new parts after all those years of touring!

While I am sure it is better now the cap was not the root cause of no spark. I was not getting any snap when cracking the points or any jump fromn the high tension lead to a head stud when cranking. I now think the original problem was a bad condenser and I just didn't do the analysis right or something. Either way the upgrades are good and probably overdue and hopefully will put many tours under our belt with little problem!

Again, thanks to all for the help and guidance- Bill

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Bill,

If I understand you correctly, do you have the continuous contact lower plate in the distributor?

If you do, it's critical that the metal piece that goes from the point set down to the lower plate makes good contact. Check this out and, if necessary, reset it. I've had similar problems and that was the cause in my car. I also have modern points.

Good luck.

Rog

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