Technical How far can a condenser go?

Once again I just got bit by the DOA condenser out of the box.
It gets frustrating to do a simple tune up and the engine will not run when finished because of bad replacement parts.

I bought a condenser from @tubman a couple years ago .... just because I thought it was cool and might be better then the **** we get today.
I did ask him at the time how far away I could get away with mounting it .... He was unsure as he never tried.

Here is what I'm working with.


What I want to do is install this condenser on the coil bracket above the distributor.

The problem is the condenser would need a wire 12" long.

So that is the question I'm asking, what can I do to make this condenser work in my situation?
It is too large to fit inside the distributor.
Is it ok to connect the condenser wire to the distributor, same place the coil wire to points go?
Or do I need to drill a hole in the body and connect and run the wire inside at the points where the original is now?
I can modify the bracket of the condenser and mount it using the distributor hold down bolt.

 

A lot of Mini racers use an external condenser next to the coil on the flywheel case with the dissy being middle of the block. So probably the same sort of distance

 

Why not use the stock inside mounted capacitor?

 

I think it's because of this. The one he's using is made by a bloke on this forum and are supposed to be pretty good but larger in diameter than stock.

 

I read in another thread were tubman said he had sold 300 of these condenser's and never had a "comeback" and the preproduction prototype has been in his 51 since 2016 with no problem.

Since you purchased the last condenser from him he may be able to shead some light on your problem.

I'm just spit balling here but could you possibly have a defective coil or coil wire? HRP

 

I need to be very clear here .... I have never installed or used @tubman condenser yet.
I bought it for a different project ..... I do want to try it.

My failed condensers are all offshore **** that has been purchased and junk on arrival.

I made a thread back in 2017 and with the help of the HAMB I found my issue was junk condensers.
https://www.jalopyjournal.com/forum/threads/no-spark-to-plugs.1052688/
I went through 3 new ones and settled on using a old used one.
Fast forward to 2024 and I install a condenser and it is junk once again.

During this time period I did purchase a condenser from tubman but I have never installed or used it.
Now I want to, but asking for help on converting to a outside condenser.
How far away can I mount it?

@HOTRODPRIMER There is nothing wrong with tubman condenser, I've just not installed it yet.

 

I think the bad -out of the box- condenser, came from the parts store.
Now in order to mount the one from Tubman, he needs a longer wire.
Just my thoughts but a longer lead wouldn’t change the capacitance of the condenser.
The second question is about drilling a hole in the body.
I’d go that, then use a part from a different distributor that was insulated, and always leave the connection inside untouched.
Hope that makes sense?

 

Mounting it 2 feet away will not change anything. It should work fine.

 

Well, took me over 3 minutes to thumb out my post

 

Giving it more thought, I can simply remove my condenser and experiment with tubman condenser.
Add a longer wire and see how it goes.

Do I need to put the wire as close to the points inside the distributor, or can it be outside?

 

My is under the trans dipstick tube in the photo. It is a Mallory 600 volt condenser for a magneto. I have one set of GM style points running off it. The lead wire is about 18 inches. It has been trouble free for going on three years.

 

Can you mount it to the distributor body like the one in the picture?

 

The difference in resistance in the longer wire is probably not enough to write home about, the issue may be quality ground path back to the distributor.

 

It will work fine . Some of the old "engine ****yzers/spark/dwell ****yzers " had a test condenser in them that allowed you to run/test your ignition if you suspected your condenser was bad. They hooked up between your coil and ground. Basically the same thing I think you are saying you want to do.

 

He hasn't got much wiggle room with that distributor in that spot.
That many faild condensors makes me want to wonder if he has another issue going on causing it though. The condensor soaks up the power from the primary circuit of the coil when the points open so you don't have it jumping the points (s****e across the points bad not good) and quite another condiion causes the failure.

 

I guess my only other question then, does it matter where I connect the condenser wire?

Factory it is inside the distributor at the points.
The points is fed by a wire from the coil and connected outside the distributor.

Can I connect the condenser outside the distributor in same place the coil wire is?
Or will I need to drill the housing and install the wire next to the points?

It is all one circuit coming from the coil to the points, just not sure if it matters which end of the circuit the condenser wire is connected to. ..... It is directly on the points wire from factory.

 

No problem connecting the Tubman condenser at the coil...it'll work just fine. Make sure it's grounded well, and that the metal it's attached to is grounded well.

 

Most very cool stuff!

 

The wire on mine is mounted to a battery isolation post. Then a 18 in lead wire to the points from the same post.

 

You can mount it where ever you like as long as it's well grounded.
You can hook it up to the points wire at the coil.
Not sure what you are working on but a good chance we have new old stock tune up kits that will fit your engine.

 

Like Moriarty, I buy old N.O.S. ignition parts at swap meets. I've run Mallory condensers that are from the 1950s that performed flawlessly.

 

Lots of English motorcycles had the condenser mounted on the coil. The coil was about 18 inches away from the points. There wasn't room in the points housing for the condenser. It shouldn't matter how far it is.

 

I'll preface this with something I posted on "The Ford Barn :

"These condensers were originally intended for use with high performance aftermarket ignitions such as the WC DuCoil in the picture provided by Mr. Coopman. These distributors require the use of an external condenser(s) because of their design, so appearance was of the utmost importance. Mine work well and have proved to be super reliable, so their use has migrated to use with stock ignitions."

The picture posted by Mr. coopman :


When developing these, we found that ignition systems can tolerate a wide range of capacitances. The longer lead will effect the capacitance of the circuit, but nowhere near enough to make a difference. (Quality capacitor testers include a set of short leads for use where there may be the need for greater accuracy.)

Even though it will run fine with the longer lead, there is a better solution. We went through this a couple of months ago and determined that the condenser doesn't care if it is connected to the distributor or the coil. If I understand your problem correctly, just connect the short wire to the coil end of the wire that runs between it and the distributor instead of the distributor end.

 

IIRC my old chev pickup had a condenser under the cap & one on the coil as well ,or am I imagining things ?

 

If it came with a radio it would have one at the coil.

 

You are not imagining it, they do different jobs. One protects the points, the other supresses electrical interferance.

Not sure what all the mystique is. A points condenser is a 0.22 microfarad 450v or 650v volt capacitor in a can, in this case a fancy machined can. They are all the same inside and should be as close to the points as possible.

 

You beat me to it. It's just a capacitor. The electronics world uses capacitors all the time, without problems. The minute they're packaged as car parts, 90% of them are duds out of the box. I'm not saying it isn't so; just that there must be more to it.

When my friend and I built my desktop computer, I emphasized that I wanted a durability-oriented build. He recommended that I pick a motherboard with Japanese-made capacitors with smooth ends, not the ones of dubious origin with '+'-scored ends to allow thermal expansion. The computer is still working after I can't remember how many years.

Surely the same principle can be applied to ignition systems?

 

I don't bother with the parts store condensers anymore, have had several DOA. A .22mF photo capacitor mounted on the coil has done the job just fine for me.
On a side note it's good to know that NOS condensers are usually good, I had a reason for believing that they had a shelf life but can't remember wtf it was now...