Spray WD 40 inside caps. All set

 

I keep reading that, lol. But there is something about spraying something flammable inside my distributor that makes me super nervous.

 

Many folks use WD 40 for years. Once sprayed, be fine

 

Ditch it and go DuraSpark II. They have a handy dandy Vented cap with a larger diameter to help prevent miss fire

Or drill a hole in your cap so condensation can get out with out letting water in,Kinda the same theory as drilling a hole in a composite head light housing that gets moisture in it

 

I've never heard of this one. Interested to see what shade tree alchemy people come up with to solve it.

 

I can't change distributors without spending a ton of money. My EFI is designed to work with it, so that's not totally a viable option. I bought some "wire dryer" spray as a bandaid. But yeah, I am thinking perhaps a vent would be a smart idea. After looking at the inside of the cap and how it mounts I don't think an o-ring will work. But maybe I put the dielectric grease at the mating point to keep the moisture from getting in in the first place. As expected FAST is useless as a way to help and act like the issue must be on my end. 3 caps in 8k miles...... just saying.

 

wait... i live in los angeles --- should I be checking my dizzy cap for moisture? I didnt know thats a thing either

 

LA is the last place short of Arizone/Utah/Colorado etc to worry about humidity. WD 40 yes yes yes. Been using it for decades after a carwash engine blast - the only way to get home short of a 2 hour layover with the cap off. It will not blow up, perhaps you are thinking you shoot it while running. Pull the cap and spray the underside. It will definitely work, just for how long will be interesting. You are welcome to go for a more expensive hassle ridden solution or take the easy way out. You may have to blast it 2-3 times a year when its hot...

 

That's odd. I used to DD mine in the snow and rain without ever having that problem. How long has this been happening ? Could you have gotten water down in the distributor that hasn't been able to dry out ? What cap, maybe it's the problematic part ?

 

The WD-40 idea sounds pretty good. After all, WD does stand for "Water Displacement".

 

the WD -40** is a good response to this issue, however, once it dried it's usefulness is essentially over. The WD stands for "water displacement". It does that by combining with moisture and accelerating normal evaporation. Once it dries out, it's not going to displace any more moisture. The residue left has a minor role in keeping electrical contacts clean. But it doesn't last very long.

**PS the "40" is the number of formulas they tried before declaring victory . Once formula # 40 was tested. they said "..this one works pretty good, Let's call it done and hit the happy hour...."


Making your own vent, as suggested. is you only viable option since you want to keep everything in place. MSD caps were very bad about moisture build up. Finally they put a vent in some of them. And I believe they have instructions online regarding drilling your own vent holes.

Here is a post by a MSD tech which you can apply to your situation:

You should also vent the cap by drilling 2 - ¼” holes 180 degrees across from each other midway up the cap between two of the poles. This will allow you to using the spinning of the rotor to draw fresh air through the cap and keep that ionizing of the collected moisture to a minimum. If this does not seem to work as well as we planned, drill an additional two holes at 90 degrees from the original holes.


The rust or corrosion is a by product of moisture being trapped inside the cap and the high energy of the MSD ionizing that moisture. By venting the cap, we use the action of the rotor to continually draw fresh air through the cap keeping the moisture down to a minimum.


Thanks,
MSD Tech ......"

Back when I was running a MSD system I had trouble with moisture build-up during a particually wet spring. I drilled the holes as suggested above, and that worked 100%

Z

 

When we get moisture in electronics at work we leave them open (cap off) all day when it's sunny and dry, dries 'em right out.

 

https://www.wqpmag.com/o-zone-todays-lesson-dry-or-not-dry
Ozone is a by product of electric discharge, and an oxidant The reason you terminals turn green
https://en.wikipedia.org/wiki/Ozone
Venting the cap lets ozone out
With metals
Ozone will oxidise most metals (except gold, platinum, and iridium) to oxides of the metals in their highest oxidation state. For example:

Cu + O
3 → CuO + O
2

 

Ozone is a by product of electric discharge, and an oxidant The reason you terminals turn green

That may be true, by why is it that 99% of people run the stock non-vented cap for years without the problems Ryan is having ? I even ran an MSD ignition, so it's not due to a "high voltage" ignition ? Seems odd to have to drill a hole, but whatever works !

 

Sounds like a plan, thanks y'all.

 

Drilling a breather hole is the best solution. Do it on the back side, half way up, about 3/32". WD can attract dust that will cause shorts. Once my car almost died because of it. Never any grease of any kind, as it can attract dust. Electrical contact grease I use on connectors. Not the same as dielectric. Dielectric is good for spark plug boots, so there are no shorts.

 

WAY back in the early days of HEI GM had that same problems and shortly discovered their HEI caps needed to have a vent for the ozone buildup. Problem solved.

 

Looks like a desiccant bag is in order.

 

Have you looked at the rotor tip distance to cap terminal? In the past I have soldered an extension to the rotor to narrow a wide gap. I also would use "Corrosion X" on the contacts.

 

have ISSUES WITH MOISTURE ON 2 of my vehicles. my truck MSD got moisture and locked up the advance. but not much trouble with the cap
the other vehicle MSD blew out the carbon tip and would goop up the contacts. started carring several caps with me after being stranded once.
Not only found deposits on the contacts but like a greasy substance inside the cap and on the rotor. wasnt leakage coming from the shaft. brake clean, carb cleaner wouldnt remove the oily substance. Began to think it had something to do with electric charge and plastic used in the cap causing it.
started using their black cap so far no oily residue.
Water in the cap solution using the what i call the distributor diaper found on factory dizzys in the last years of the dizzys helped a lot.
Cleaning caps would scrape off the corrosion build up then immersed the cap in vinegar for a few days then sprayed out with brake clean and blast of compressed air.

Before and after soak

 

Slot car racing level maladezo

 

Who said anything about staying on the track? I just shoot it with a slingshot, pick it up, then shoot it back!

 

Put a bead of dielectric grease around the edge of the cap to make a seal


Sent from my iPhone using Tapatalk

 

Pretty good way to keep actual water spray out but sealing with grease wouldn't help with ozone venting at all I believe.

 

If a car sits for a long time through the winters, the whole distributor will have rust issues, in my experience. It amazes me how bad the moisture in the cap can be, year round.

 

@RyanSterling966 I know this is an older post, but I was wondering if in the time since you were able to find a solution besides buying new caps and rotors? I'm also running a FAST dual sync for my EFI and after about 4 years I've started running into the same trouble as you've described.

 

I had this problem back when I was 16 with my I6 stuff, and it turned out that the distributor cap had a hairline crack in it. It wasn't obvious at first glance.

The vent idea like the Duraspark caps seems like a viable option.

Maybe there is some sort of small issue with the design of the FAST dual sync setup that makes it prone to this happening.

I have a Pertronix distributor and the only times I have even really gotten moisture inside the cap were when the engine got wet a couple times.

 

Spray a silicone spray inside. Be fine