Condensation in the Dizzy Cap

[hrafn]

I switched to a civilian style ignition setup last summer and I thought that I
was happy with it except that it has left me sit three times so far. Once was
because the Pertronix coil failed. Twice it was because of condensation in
the distributor cap. I never had any issues with the OEM setup except, of
course, with the price of replacement parts .

The condensation issue has always happened in times of extreme rain and
temperatures near freezing. The truck will run fine, but after sitting for a while it won't
restart and acts like the timing is off (way off). Upon pulling the distributor
cap I always find a lot of condensation in the top of the cap. I now carry a
few extra caps so that I can be quickly on my way again.

The vacuum line is in place and I have vacuum at the distributor, but isn't the
vacuum just pulling in wet air? As I mentioned, I never had this problem
with the stock cap. Has anybody else experienced this problem?
What was the fix?

Thanks,

[Foz]

I wrap a single layer of vinyl electrical tape just above the bottom edge of the cap so that when clamped down it forms a bit of a seal... seems to have helped a great deal.

[75pinz]

I had the civilian ignition and it gave me some trouble in wet weather. The military ignition did not. I would say the only advantage I saw was in my wallet. I didn't need the upgrade anyway I don't think. Just a way for me to spend money on crap I didn't know I didn't need.

[russ]

Make sure vacuum line is working correctly. I had same problem and line was clogged. It does remove condensation quite well.

[hrafn]

A few more episodes of condensation in the dizzy cap. It´s starting to piss
me off.

A comparison of the original military cap to the "civilian" cap shows that the
military cap is taller and has a longer distance between electrodes because
of the towers surrounding the electrodes. This is probably why the military
cap is less prone to short out from condensation.



I think I may go back to the military cap, plugs and wiring. Better than being pissed off...

[ExpeditionImports]

You are chasing demons. With a thin coating of RTV between the cap and adapter, your civilian cap is just as "waterproof" as the stock cap.

Are you aware that your existing "waterpoof" distributor has 6 large vents in the base of it? Pull the distributor and turn it over and they are evident.

The problems you describe we usually see when the brass valve (middle of the rubber elbow on the condensation line) has been removed from the system. This causes a very pronounced vaccuum that tends to suck in a lot of moisture through above mentioned vents in the distributor. That would be the first thing that I would check.

How tight is the cap in the adapter? Any slop? It should be a very tight fit.

Are you using a Bosch cap, or some of the auto store crap...there is a difference between some of them. Can't speak of the other cap adapters on the market, but ours is designed for the Bosch cap. I can tell you that the Carquest caps do not fit in our adapter very well at all.

Make no mistake, the primary purpose of the stock ignition system has nothing to do with being waterproof. It's purpose was for radio noise suppression so that communications on the radio equipment would not be an issue.

Cheers,

Scott

[russ]

I will take some pictures of my ignition tomorrow before I put it all back together for the Orlando Military Vehicle meet.

I have gone with a civilian ignition. It is now sealed. Final test was to hose it down while engine was running. Hose and buckets of water. No problems. I have the VW sand rail covers on coil and cap (~$5.00 for both). Make sure the points wire that runs from the side of the distributor to coil is sealed, I eliminated that braded cover and now have a hose with shrink tube on both ends to lock it down. If not and you hit water that vacuum hose will suck in water like a straw, even with limiting valve.

I've had this basic setup for a while and driven through some pretty deep water with no problems. Last trip out the coil cover leaked a little and caused a problem so it is now all redone with some changes.

Again, if you don't have the vacuum line you will eventually get condensation. It only took one outing for me to find this out. It does need the limiting valve/pinhole and like Scott said the bottom sealed up.

[milesdzyn]

Jay....when you drilled out the old cap what was holding it in place? Did you damage the metal canister at all. Any part numbers?

Miles

[hrafn]

Jay....when you drilled out the old cap what was holding it in place?
Did you damage the metal canister at all. Any part numbers?

Miles

Miles,

I didn't drill out anything. I dug out the potting compound so that I could get
at the three screws that hold the bakelite inner cap to the outer metal shield.
The cap has a Bosch part #1 235 522 063. Let me know if you find any at a
reasonable price. The outer metal shell was not damaged and should be
reusable almost indefinitely.

Make no mistake, the primary purpose of the stock ignition system
has nothing to do with being waterproof. It's purpose was for radio noise
suppression so that communications on the radio equipment would not be an issue.

Scott,

I am aware of the original design and have no illusions of making the
system waterproof. Also, are you absolutely sure that the vacuum is
there to draw away moisture? I'd be willing to bet that the vacuum is there
to pull oil into the top bearing of the distributor.

[ExpeditionImports]

Absolutely sure, nope. However, the bosch distributor used in the Pinz is the identical distributor used in the Unimog, Haflinger, Iltis, etc. All of these vehicles do NOT have this line, and bearing failure of the distributor shaft is not considered a common problem. The mounting of these distributors on the other vehicles is also not in direct line with the air tunnel and incoming rain, etc. The hypothesis has been that Steyr added the line to evacuate moisture from the distributor.

Assumptions: It requires MUCH less vaccuum to circulate Air than to Move Oil. The distributor is vented. If the purpose of the line was to pull oil up to that bearing, then you would not want to vent the distributor as that would defeat the vaccuum effect on the oil, or hugely reduce it. (IE you have a brass jet to severely regulate the vacuum suction, and 5-6 larger holes in the distributor to flow air.) However, if the intent was to circulate air to eliminate condensation....then a vented distributor would do exactly that.

Add all of the above up, plus that fact that when a truck has a condensation problem, we repair the line (clear clog, or add valve) and the problem goes away.......but everybody's got an opinion.

Also keep in mind, there are well over 1000 of the cap adapters in the marketplace. How often are we hearing about condensation problems? Pretty rarely, and usually when the condensate line is fixed the problem goes away.

Cheers,

Scott

[mjnims]

Jay
I have the electronic ignition system from EI. I also had a lot of water problems when initially installed. I simply put a little silicone on the cap and all has been good. I know some have gone as far as to cover the vent holes on the bottom of the distributor to keep the water out in the first place.
On the concern about oil for the lower bearing in the distributor. The owners manual suggest occassionally putting a few drops of oil into the distributor to help keep it lubricated.

[Foz]

I think perhaps an addiitonal function of the mild vacuum and inlet vents is the reduction of ionization of the air volume. By changing the air volume every few minutes - I wonder if the system yields a less corrosive environment not just by changing moisture levels inside the dizzy - but also the intensity of the ionic charges carried by the air volume and dust motes carried therein.

Anyhoo... what is the state of the o-ring on the top face of your dizzy body?

If this worn to flush such that your adapter plate is pulled all the way down to meet the face when mounted... it will cover the inlet holes and you get no draw on the vacuum system. If so, renew the o-ring or fashion a thin gasket to assure a small gap between the lower side inside diameter of the adapter plate and the top face of the dizzy body so air can bleed through the system.

[milesdzyn]

I wonder if one of the unintended benifits of the military caps, in terms of collected condensation, is the inner and outer caps have a insulative quality. Simaler to double pane windows collecting less condensation on the inside surface. Giving me a idea that you may want to try, insulate the civilian cap. Just a thought.

Miles

[Foz]

I dunno... seems the warm moist air in the dizzy would still cool and water would condense regardless... I think as Ingham explained that mil cap is all about radio noise.

[Tony]

I think it would be a really great improvement if the posts on this thread could be extended in length so that everything could be expressed in a single line, rather than in seperate sentences and paragraphs.

By that I do not mean the number of words contained in the message, I mean the length of the message measured in feet from left to right.

A single well crafted message might be able to streach on for several meters.

Here is an example of what I mean.

DDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD.