Bad Condenser Symptoms?

[Wilbur]

What symptoms point to a bad condenser? My 29, which has a new distributor with modern points, acted up something terrible lat night on a 50 mile run. It started with a random miss at 45 mph, and within 15 miles, we were limping along in first gear, bucking and powerless, with an occasional backfire out the carb. It acted as it had in the past, when the sloppy point block on my old distributor allowed the point gap to reduce to almost none. I pulled over and found the gap to be fine. The cap, rotor, points and condenser have maybe 200 miles on them. The coil is not new.

It was blowing snow and we were dressed in full 20's garb to attend the Rum Runners Ball in Cape May, NJ, with 5 miles to go! We limped to the party and left her there for the night. Any ideas would be appreciated.

[Tom Wesenberg]

What your car did certainly could be a bad condenser. The easy check is to hold the coil wire 1/4" from a head nut and crank the engine with the key on. You should have a strong blue spark. A wimpy yellow spark is no good.

[hardtimes]

Hey Wilbur,
Hm, long distance diag of your stated symptoms..is crap shoot, but I'll start it off by saying that what you describe could be the results of a failing condensor. However....same symptoms could result from fuel starvation (i.e.-dirt in fuel line/carb float not right). You say you did dist work...'and it acted as in the past'. Well, that's evidence, IMO, that mabe something other than dist is THE problem. Like said, hard to diag from distance, but have you checked for loose/bare wiring/grounds; do you have original ign cable ...is it screwed into dist..just a tad TOO far (that will do it also) Is your dist grounded GOOD to engine or sitting on thick paint? Some place to start,eh. Let us know the fix, when you locat it.

[Wilbur]

Last night l was thinking maybe a blown head gasket. l'm working on it now and am going to do a compression test and look at the spark jumping. The plugs are all wet with fuel. I had the Tilly carb apart a few months ago, straightened the housings in the oven and have the float set good. The glass sediment bowl looks spotless, so at this point l am leaning toward an electrical issue and will repost later.

[Wilbur]

The spark looks hot, blue and jumps a good 3/8". Compression came in low, but consistent with this old girl. Between 54 and 65 psi, so the head gasket or a stuck valve is out. The cam nut is tight, but timing may be the issue. Gonna get out the test light and check timing as per Les Andrews red book next. Any thoughts?

[John Kuhnast]

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I have seen other answers were they say hold the wire near block to check for spark. Are they saying hold it in your hand or with some nonconducter ? I know my model T knocked me about 10 feet.

[1crosscut]

How many miles do you have on your "new distributor"? Was it running ok before you changed it?
Dave

[Tom Wesenberg]

Originally Posted by John Kuhnast

I have seen other answers were they say hold the wire near block to check for spark. Are they saying hold it in your hand or with some nonconducter ? I know my model T knocked me about 10 feet.

You should be fine by holding the wire on the insulated part. If not, then the insulation is bad.

[Wilbur]

Hey, lookie here, just set the coil wire near some steel and let it go, Jack! Anyhow, the timing check went fine. She is spot-on. This new, modern distributor, from Snyder's, has about 200 miles on it and has run fine up to now.

My old one just needed a new point block, but l decided to get a new one because the bushings were pretty sloppy on the shaft.

[Bob C]

Some ignition problems can be heat related so if you did the spark jump test with a cold engine
the problem may not show up.

Bob

[P.S.]

It started with a random miss and gradually got worse. Hmm.. I'm no expert on motors, however, I do know a lot about electricity.

The plugs were wet with fuel- No fuel starvation problem.
The spark is strong and blue- No coil/condenser problem.
Compression is good- Not a valve problem.

A possibility is to look for cracks in the distributor upper housing (the thing that the spark plug straps go to) and the dist. cap. Look for signs of arcing inside the bakelite parts. Had this happen on mine when I first bought it. Drove me nuts trying to figure it out. Same symptoms as you describe. As the arcing continued, it left carbon, which caused more arcing, which made more carbon, etc. Finally, the car barely ran. Replaced the dist. housing and it ran perfect again.

[Mitch//pa]

you might have a good spark now but check it while it is acting up with an inline spark tester. alot of times ignition is intermittent, so do your testing when the problem is happening

[clo2jim]

I had the same problems when I was at the Dallas Meet. I changed the condenser and had no more problems

Easy simple fix

[Wilbur]

PS. Good idea! We did look for stray sparking last night in the dark, during the snow storm and saw none. However, looking for carbon tracking is a great one. Thanks. This morning, l had the car flat-bedded the 50 miles back home ( that $12 towing extra on my JC Taylor policy is fantastic ) and had tried to start her, cold, at that time with no luck... the plugs were all fouled from limping to the party.

[Wilbur]

Are condensers voltage specific..as in 12 volt and 6 volt?

[MikeK]

Originally Posted by Wilbur

Are condensers voltage specific..as in 12 volt and 6 volt?

No. They do have an overall insulation breakdown rating, probably about 500V for an unpolarized ignition coil capacitor. They often fail in intermittent ways, though.

[Wilbur]

Ok. Here's where l am. Decided to try to start it up. Installed new plugs, put the same cap and rotor parts back, turned the gas on and cranked her over. No start. Pulled the coil wire off the cap. Cranked it over, key on, and had no spark. Key off, checked for 6 volts at both coil terminals. Good. Removed cap and rotor, turned the key on, put the coil wire near a ground and manually opened closed the points to trigger a spark out of the coil. A quiet arc occurred at the points and, maybe one in 8 times, l got a high voltage spark out of the coil wire to ground. So, whats bad there... coil or condenser? Can anyone explain to me what the condenser does?

[MikeK]

Originally Posted by Wilbur

. . . Can anyone explain to me what the condenser does?

The ignition coil is a high ratio transformer. Transformers do not work on straight DC. The magnetic field must be moving to induce electrons to move in the windings.

When the points open the ignition coil magnetic field collapses (moves) and induces an electro-motive force (voltage) in the primary as well as the secondary coil. It's not very much in the primary coil because there are only a few windings in the primary, but it's enough, maybe up to 200V, to jump a small air-gap such as the one between the barely open points. That tiny spark is enough to erode metal away from the points and you'll burn up the points in a matter of minutes. The condenser (capacitor) is an electron reservoir and prevents the points from arcing by absorbing the induced primary voltage rather than letting it arc wildly across the open points.

If you have a solid state (transistor) switch instead of mechanical points there is no air-gap to ionize and maintain an arc, so no condenser is necessary. Example: Pertronix "ignitor" modification. Of course, that mod has it's own set of problems!

[Wilbur]

Mike, thank you for the explanation. Given the details, what's your opinion of my issue? Is my coil done for?

[Mitch//pa]

Am I reading that one in eight times of manually opening and closing the points you got a spark? If so clean the points with a file and regap and try it again

[Wilbur]

The points are clean, and only have about 200 miles on them. Each time l opened them, a small spark occurred there, but the high voltage spark from the coil wire only occurred once in a while.

[Duffy1]

I bought the same dist you bought from the same vendor . Installed the dist . car would not start took dist out and apart found incoming wire touching housing . Moved wire off of housing put dist in car and started her up . Car ran for about and hour and then had the symptoms you describe. Lets see new dist ,points , cond . so can not be these three items so was thinking about working on the carb then I rembered what I had read on FB that 95% of carb . problems were electrical so I thought the situation and decided to change out the condenser . Problem solved . Also replaced the point with more robust points from NAPA . So I wonder if these dist are not tested prior to sales .

[Karl]

Faulty ignition switch can cause exactly the same problems you are describing Karl

[steve s]

Why haven't you tried a new condenser--or your old one?

Other straws to grasp at are loose connection on the ammeter (applying a jumper wire across the junction box terminals is a temporary fix/test for that) and a dying ignition switch (I've replaced about 6 of them in my career--they'll make you crazy).

[Mitch//pa]

With a testlight one side of the coil should have a constant 6v. The other should flash the testlight everytime you open and close the points with the key on which fires the coil.
This would prove out the other wiring,switch etc

[MikeK]

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Originally Posted by Wilbur

Mike, thank you for the explanation. Given the details, what's your opinion of my issue? Is my coil done for?

All of the possibilities the fellas have suggested are plausible, and that makes it kinda fun, like playing "Clue". When it gets too drawn out, like a monopoly game stalemate (3 days!!) the fun dwindles.

I'm not one to react like a modern car pseudo-mechanic and suggest you just start replacing parts 'till you win, but a condenser is a part that is difficult to check under actual working voltage, engine heat, and frequency conditions. It is cheap and easy to swap out, so I'd start there. A meter test will tell the static capacitance and DC leakage, but that can be deceiving. If it is not the condenser, that's OK, it's always nice to have a known-good one in your trick bag of Model A tidbits. Go from there.

A coil is also difficult to test under heat and working conditions for internal insulation break-down and partial winding shorts. It is EXPENSIVE, so I'd run down everything else suggested in the replies first, unless you have a dizzy test machine or you're Rockefeller or have a bucket full of spare Model A coils, one of which may be good.

It was Professor Plum in the library with the candlestick. Do I win or am I out?

[Wilbur]

Being a Sunday afternoon, l lacked a spare condenser to try. I do have spares for my original unit, but not for the modern upper plate. Spares will be in my ditch bag from now on! Gonna hit NAPA tomorrow for both a coil and condenser.

Mitch, I put a meter on the coil terminals and had 6.2 V on each side with the key off. I didn't try a test light to see if it flashes when the points are manipulated. It's beer time! I'll try it tomorrow. Thanks.

[Tom Wesenberg]

If the switch, wires, and connections are good then I'd try the condenser first, and points next. I've seen points new out of a sealed box that didn't work even though they looked clean and good.

[P.S.]

Originally Posted by Wilbur

Being a Sunday afternoon, l lacked a spare condenser to try. I do have spares for my original unit, but not for the modern upper plate. Spares will be in my ditch bag from now on! Gonna hit NAPA tomorrow for both a coil and condenser.

For testing purposes, you could simply connect one of your other condensers to the + side of the coil terminal itself and ground the condenser to the firewall.

From what it sounds, based on your spark 1 out of 8 times you open and close the points, I'd certainly blame the coil. This really does not sound like a condenser problem, unless the condenser was very leaky and nearly shorted. If you can, please remove the wire from the condenser and put an ohm meter from the wire to the condenser case (ground). The ohm meter should start at some decently high resistance and then climb up in resistance until it shows infinite open. If not, then it's bad.

[Wilbur]

So, l put a new condenser in there and she runs like a champ! Another victim of the fine quality of outsourced manufacturing!

[Mitch//pa]

Glad to here it

[steve s]

Originally Posted by Wilbur

So, l put a new condenser in there and she runs like a champ! Another victim of the fine quality of outsourced manufacturing!

Now, you're always going to carry a spare, right? As with umbrellas, always carrying one is the only way to guarantee you'll never need one.

[MikeK]

Now that one becomes your spare. Write tested OK and the date or something like that on it with a marker. Go get another one.

[Tom Wesenberg]

And be sure to destroy the bad one, so it doesn't get mixed in with good parts or accidentally used.

[Wilbur]

Excellent ideas. Keeping this good one as my spare.... Great. However, the one that let me down Saturday night had run fine for a few hundred miles.

[Tom Wesenberg]

Originally Posted by Wilbur

Excellent ideas. Keeping this good one as my spare.... Great. However, the one that let me down Saturday night had run fine for a few hundred miles.

A few hundred miles is nothing. It should have lasted many years and thousands of miles. Use a tubing cutter to open the case on the bad one, then you'll have something to take to the next club meeting for show and tell.

[Tom Wesenberg]

If you have an original Ford script bad condenser, you can carefully open it up and replace the insides with a modern part. I did a couple just to see how hard it would be to do it and to see how well it woould work. I'm still using one of these in the picture, which I cut apart and changed 3 years ago.

It's tough to unroll the crimped end, so the second one I did I used a tubing cutter and soldered the seam.

[larrys40]

Wilbur,
Wow.. lots of good posts! Troubleshooting should be a very logical path to get to the core of the problem. Do you have a digital volt/ohm meter. If so, start checking for voltage and any drop in your primary (low tension side) of ignition. Dist. cap/rotor out, check voltage at points ( open) , coil, igntion switch... voltage should be roughly the same. If not you have a bad connection somewhere.

A high percentage of carburetor problems are electrical. check and make sure all your connections are tight., coil wires, ignition switch ( yes, you could have an bad /intermittent ignition cable/switch), Even though it's a "new" distributor have you pulled the cam up and upper plate up to make sure there isn't a lower plate/screw loose/pigtail issue, or otherwise. Lower plate not shorting anywhere, including ignition cable not screwed in too far causing lower plate to short against housing. I like gluing a small piece of rubber as an insulator when doing housings where the lower plate would fit close as insurance when the cable would be screwed in. Some cables have a longer plunger than others.

Finally, yes, you have checked all the essentials, gap, retimed/timing,spark. I have also seen where the rotors cause these kind of problems, even hard-no start or hard start and poor running. Sometimes it's little witnesses, like a small wear hole in the rotor, so small you can barely detect it... and it causes the high tension spark to go through the rotor. so... have you tried a new rotor and cap. Cap quality varies greatly. Is the rotor tip aligned to the body? Little things... pay attention to detail, use your meter, troubleshoot logically. Make sure you have correct consitent low tension voltage where it should be, if not, find/fix problem, then ensure high tension side is OK.
Test... Don't guess! ( that's the old Sun Slogan)

If you have someone who is electrical/test equipment equiped/savoy, you can always have your condensers and coils checked. I do them on an early Ford Heyer test set so I know exactly what is good and bad. Model A condensers should read .20-.25 microfarads, coil primary about 1.2-1.4 ohms, high tension 10KV-18KV (need proper test equipment for this, no meter).

With a good calm, logical path, non shotgun troubleshooting tecnique I'm confident you will locate the trouble.. and learn in the process. It is the best way. Good luck
Larry Shepard


p.s., yes at 55lbs your compression is fine, not low, and your spark plugs are wet because to too much fuel ( choke from trying to start). ensure plugs are clean, gapped properly, and tight.

[larrys40]

Tom,
That was a lot of work! I love to see detail to those lengths! If your really desperate and need a nos ford there are some out there... IF you can't find drop me a PM. I have them from time to time. I like the A&L burnout proof units for service. They are fit and functionally the best. Unless you're going fine point there is no other to use.
Larry

[ghswen]

Hello to all.

I joined this forum today to post in this thread. I have one of those 'new' Fords (a 1963 Ford Ranchero). I did a 'google' search for 'symptoms of bad points' and your forum came up 2nd. After reading this post I realized that Wilburs problem was exactly the same as mine. Started random missing, kept getting worse to the point of not running. I had changed the points and condenser about 2 weeks before so I figured it didn't make sense that it could have been either, however the symptoms pointed that way. I knew I was due for a rebuilt carb anyway and had the chance to get one at a good price, put it on and still no difference. Changed fuel pump and filters still the same problem. Finally did my google search and found your thread. This morning I swapped out the condenser and she fired right up! With the new carb she runs like a new car! Even with the success I have ordered a Pertronix electronic ignition to eliminate the points / condenser.

Again I just wanted to say thanks for a great thread!

Gordon

[Purdy Swoft]

Lots of things can go wrong with electronic ignition that will leave the model A dead, side of the road or in the road. Most that run electronic carry an original timed distributor for when the electronic setup fails. Most don't really trust electronic but peer pressure often causes them to try and use it. Same with V8 points setup. Its really the modern setup that causes the problem, foreign parts and parts that were not designed for the model A distributor. I really can't understand why so many think that such a make shift set up is SO cool. The only time that I couldn't make it home with the original style points setup was when the rubbing block came off of the old JC Whitney points and that was over 20 years ago. Good original style points and condensers are available from most model A vendors. I've run the same original style points and condenser in my 31 sedan for 13-14 years. Good luck

[TDO]

Had the same problem with the modern points from Snyder's , I got less than a 100 miles on the condenser.

[Patrick L.]

Originally Posted by TDO

Had the same problem with the modern points from Snyder's , I got less than a 100 miles on the condenser.

For some reason the ' A ' vendors tend to stock the 'cheap' points and condenser [modern]. I don't know why. A good local parts supplier should have or can get quality points and condensers, but, they are expensive. These are the same for any Ford V8 from the 50s to the 70s.

[Purdy Swoft]

Napa has the expensive V8 points. most modern cars haven't used condensers in forty years or better. Theres not much demand for good modern condensers , I wouldn't think. The short proof A&L condensers and good original style points are available from most model A parts vendors for less than half the price. NAPA also handles standard model A points. What is suppose to be better about the hard to work with V8 setup? I had bad results. Its not a good feeling when the A sputters a couple of times and you are coasting hoping to find a place to pull over before it stops. Its not good when you are ready to leave the gas station and the A won't crank. No amount of coaxing cussing, or praying will bring it back to life unless you've got another set of modern points and condenser. I must have been crazy for the years that I struggled with them.

[JD 1931]

there are some inferior condensers sold out there (parts supply houses), had bad new one , went with NAPA's best ,ran great.

[Joe/Ct]

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Originally Posted by Wilbur

What symptoms point to a bad condenser? My 29, which has a new distributor with modern points, acted up something terrible lat night on a 50 mile run. It started with a random miss at 45 mph, and within 15 miles, we were limping along in first gear, bucking and powerless, with an occasional backfire out the carb. It acted as it had in the past, when the sloppy point block on my old distributor allowed the point gap to reduce to almost none. I pulled over and found the gap to be fine. The cap, rotor, points and condenser have maybe 200 miles on them. The coil is not new.

It was blowing snow and we were dressed in full 20's garb to attend the Rum Runners Ball in Cape May, NJ, with 5 miles to go! We limped to the party and left her there for the night. Any ideas would be appreciated.

I know that you solved your problem, but we experienced something very similar. In our case, the engine just stopped running. After a lot of investigating, including the change-out of condensers, it turned out that we had a totally blocked fuel tank filter. That was the problem, even though the sediment bowl appeared to be full.

[MrTube]

Do what Tom does and install a new capacitor inside the old housing.
While there may not be many quality "condensers" out there made for automotive use there are plenty of modern capacitors which are all infinitely better than any cap made even in the 1960s.


I'm willing to bet Tom has had few if any failures with his modified ones.

[Tom Wesenberg]

MrTube, I did this just to try it out and then installed it in my 28 to make sure it was going to work OK with the heat. I was going to remove it after a week, but it's still in there 5 years later. Might as well leave it.

[MrTube]

Originally Posted by Tom Wesenberg

MrTube, I did this just to try it out and then installed it in my 28 to make sure it was going to work OK with the heat. I was going to remove it after a week, but it's still in there 5 years later. Might as well leave it.

I half asleep so I may be looking at this completely wrong.
But, would it be possible to move the cap into the dash connected between ground and the key? This would give you more room and get it away from heat.

[Tom Wesenberg]

Originally Posted by MrTube

I half asleep so I may be looking at this completely wrong.
But, would it be possible to move the cap into the dash connected between ground and the key? This would give you more room and get it away from heat.

The only problem would be if it shorted you'd have power running through the coil, just the same as mounting the capacitor on the coil. I don't have a problem with it in the distributor, as original.

[MrTube]

Originally Posted by Tom Wesenberg

The only problem would be if it shorted you'd have power running through the coil, just the same as mounting the capacitor on the coil. I don't have a problem with it in the distributor, as original.

Thought you were concerned about the heat?

[Purdy Swoft]

It would work. one problem might be that its pretty close under the instrument panel to add anything else. The coil in the model A is live or hot all the time no matter where the condenser is mounted. The only problem that I see is bad cheep china condensers no matter where you choose to mount them.

[MrTube]

Originally Posted by Purdy Swoft

It would work. one problem might be that its pretty close under the instrument panel to add anything else. The coil in the model A is live or hot all the time no matter where the condenser is mounted. The only problem that I see is bad cheep china condensers no matter where you choose to mount them.

Ah but that's the point in hiding it behind the instrument panel is now, you can buy a quality capacitor and hide it. I can assure you buying a Panasonic, Spraque / Vishay or any other number of quality brand name caps will not be like the cheap junk they sell for the "A" that is stuffed into an original looking housing.

[Randy in Illinois]

I had a problem like yours, after replacing condensers I found the wire loose on the pop out switch. the nut fell out when I removed the insturment panel. I use the same insulated nut as the ampmeter.

[Purdy Swoft]

Originally Posted by MrTube

Ah but that's the point in hiding it behind the instrument panel is now, you can buy a quality capacitor and hide it. I can assure you buying a Panasonic, Spraque / Vishay or any other number of quality brand name caps will not be like the cheap junk they sell for the "A" that is stuffed into an original looking housing.

I agree, a quality condenser will work. The condensers that most are having problems with are the modern or V8 style condensers that the model A venders and many others sell. The new original style model A condensers that Snyders, Bratton and other good model A venders sell are the short proof A&L condensers that give no problem.

[Purdy Swoft]

If a quality condenser like the ones that Mr Tube refers to could be mounted under the dash panel, just below the windshield. The condenser would get plenty of cooling air in summer with the windshield let out , if mounted in this manner and it would be hidden. Length would need to be added to the pig tail of the condenser. The wire could be run through the slot at the top of the instrument panel where the dash light enters on the 30-31 instrument panel and connected to the ignition switch where the red wire connects. This would give the same results. The instrument panels used on 28-29 models could have a slot for the wire filed in the panel for the wire to enter.

[glenn in camino]

My guess is that the points are closing because the new rubbing block has worn down. Solution, reset points, lube cam and drive.

[marc hildebrant]

Group,

The capacitor (condenser) has to be installed close to the points to work properly.

If it's located away from the points, the inductance of the wire between the cap and points will work against the operation of the cap.

Marc

[Purdy Swoft]

Funny thing that its been working for me for the past six years on this one

[Purdy Swoft]

HHere is another . Hot dam, the site is acting crazy but i've actually got a couple of my pictures to post offen photo bucket. I can't put the print where I want it but I'm ah putting it any way I won't lead anybody wrong. If I say it works, I've done it and usually have pitchers to prove it. Ain't that rust on the radiator brace rod purty.

[Purdy Swoft]

One more while I've got photo bucket working, just couldn't resist. This is my sept 29 that I've had since the spring of 1960. I must know something. I've been doing all of the work on mine since I was 13 years old. Now probably in my september days.

[MrTube]

Originally Posted by marc hildebrant

Group,

The capacitor (condenser) has to be installed close to the points to work properly.

If it's located away from the points, the inductance of the wire between the cap and points will work against the operation of the cap.

Marc

Why would the wire mean anything being the back emf is coming from the coil it self, not the points? I would think, the closer to the coil the better?

I think the proof is in the pudding and it sounds like Purdy has not been burning points.


How long will it take to destroy points without a cap? As in, if you get stranded because the cap shorted can you just pull it out and run without it, or will you only make it a mile or 2 before the points are toast?

[MikeK]

Originally Posted by MrTube

. . . How long will it take to destroy points without a cap? As in, if you get stranded because the cap shorted can you just pull it out and run without it, or will you only make it a mile or 2 before the points are toast?

You may not get a spark at all, or at best a very weak one. Without the cap to directly absorb the reverse EMF the waveform falls at a much shallower and irregular slope, as the electrons must wait their turn to arc across the points. If it does run, the points will be toast in about 20 minutes. I've seen this demo on a dizzy machine with a scope.

Unrelated subject- I'm clueless as to why only half of your monitor top valve seat corrodes. Turbulence erosion?

[Patrick L.]

An open condenser ? Engine won't run. Unhook it and see if it'll run.
Length of condenser line/wire ? I don't think it much cares. Those little electrons can run faster than you think.

[MrTube]

Originally Posted by MikeK

You may not get a spark at all, or at best a very weak one. Without the cap to directly absorb the reverse EMF the waveform falls at a much shallower and irregular slope, as the electrons must wait their turn to arc across the points. If it does run, the points will be toast in about 20 minutes. I've seen this demo on a dizzy machine with a scope.

Unrelated subject- I'm clueless as to why only half of your monitor top valve seat corrodes. Turbulence erosion?

Ah, that makes sense. So the cap is needed for the circuit to work properly as well as protect the points.

Unrelated - Not sure on the valve seat, I'm wondering if its flash gas which apparently is also a big problem in modern day units destroying TXVs. I'll probably never know why its happening but the cap tube will solve the problem anyway.

[marc hildebrant]

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Originally Posted by Patrick L.

An open condenser ? Engine won't run. Unhook it and see if it'll run.
Length of condenser line/wire ? I don't think it much cares. Those little electrons can run faster than you think.

The inductance of a long wire to a remote cap. is the problem. That's one of the reasons why the cap is near the points.

Marc

[Purdy Swoft]

I've had NO problems with a longer wire or connected directly to the coil. When I got my first model A some parts had been removed. It didn't run and there was no condenser.I was only a teenager. I didn't have the correct condenser and there was nowhere to mount a modern style condenser in the model A distributor. I removed the condenser from a fifties model chevy six cylinder and mounted it on the firewall. I cut the clip off the pig tail skinned the pigtail wire and twisted on a longer wire. I run this wire down to the distributor and connected it to the lower plate and it worked good, really. It was just common sense to me and I really had nothing to lose. I was later shown by an older guy how to connect the condenser directly to the coil. Both ways work good. Good modern condensers were available at parts houses in the day. the object was and is to get the condenser away from the heat of the exhaust manifold. Of course this ain't original but is a novelty to me.

[Patrick L.]

Originally Posted by marc hildebrant

The inductance of a long wire to a remote cap. is the problem. That's one of the reasons why the cap is near the points.

Marc

Shhhh. Can't say that too loud. Can't allow the car to hear it. It might decide not to run.

[MrTube]

Originally Posted by marc hildebrant

The inductance of a long wire to a remote cap. is the problem. That's one of the reasons why the cap is near the points.

Marc

Originally Posted by Patrick L.

Shhhh. Can't say that too loud. Can't allow the car to hear it. It might decide not to run.

I still want to know why the points matter at all when it is the coil you are working with? The back emf is coming from the coil, not the points.

So doesn't it make more sense to have the cap by the coil? Shorter wires!

[Patrick L.]

Originally Posted by MrTube

I still want to know why the points matter at all when it is the coil you are working with? The back emf is coming from the coil, not the points.

So doesn't it make more sense to have the cap by the coil? Shorter wires!

The points are only the switch. The condenser is actually what feeds the coil, so to speak, simply put. And yes, if you're worried about wire length then the closer to the coil, the better.

[MrTube]

Originally Posted by Patrick L.

The points are only the switch. The condenser is actually what feeds the coil, so to speak, simply put. And yes, if you're worried about wire length then the closer to the coil, the better.

The battery feeds the coil, not the cap. The cap seems more like a shunt than anything.

[P.S.]

Just spotted this conversation.

The coil stores, and releases the high voltage energy when the primary circuit is opened. When the primary circuit is opened by the points, there is a natural tendency of the points to spark. The condenser helps suppress that spark so it does not become so violent as to damage the points surfaces quickly.

Second (and most important), the condenser provides a ground for the bottom end of the coil secondary against which the coil works to produce the high voltage spark as the field collapses.

[Patrick L.]

Originally Posted by MrTube

The battery feeds the coil, not the cap. The cap seems more like a shunt than anything.

Yes, and, no. Google is a wonderful thing. There is more reading there than one can handle. Of course, like a lot of things on the internet, some are wrong. But, they can be filtered out fairly quickly. Ignition systems are pretty simple, but, at the same time, complex.
Why a condenser is called a condenser is beyond me, its just the way things are. But, its function is pretty neat.