Sealing up distributor...do I need a vent?

[Deerhunter30]

I like to make mods on my Jeep based on previous trips. It appears that during water crossings my distributor always gets wet and kills my power. I do not think that I am even submerging the distributor. What I wanted to do is put some silicone around the base of the distributor cap to seal it to the base so water does not get in. My question is, do I then need to vent the distributor? I thought about drilling a hole in it and then glueing a vacuum line fitting to it and running a vacuum line up to the top of the firewall to vent it. Is this necessary? Any advice?

[Bounty__Hunter]

I dunno, but my 4banger's cap has a vent built into the design, it's got a small cap on top that allows air in and out.

[Tug-n-pull]

Something that I do rather than seal up the distributor is just use a good electrical lube on all the wires both ends and all around the contacts in the cap where the rotor button makes contact. The lube I use is in a .99 cent packet from autozone. I also run a bead of the same lube around the base of the cap where it mounts to the distirbutor itself. This also makes the plug wires pull off easly when you go to remove them. Another thing I have started to do is useinf zip ties I place one around my plug wires in groupes of 2 or 3 going in the same direction then put another one between each of the wires to keep them seperated and off of any heat source. this has proven to be worth the effort in the life of the plug wires. I also use a water displacement silicon spray inside the distirbutor. I find this all to work together to prevent the drowning out problem for me. But the best thing I have found so far is to avoid the mud and water as much as posible when out on the trail. I hope htis all helps a little. As for a vent I have no real answer but if it works for you let us know. tug

[firemanharry]

You will need some type of vent to prevent condensation if you're going to completely seal the distributor with silicone. You may be able to find a vented cap. If not just use a short hose with a cap similar to those on your rears. I had the same problem with mine. I never submerged any of the ignition system, just seemed to wet out from water spinning off the fan. The electrical spray sealer worked good for a short amount of time but eventually wetted out too. I was going to seal my cap, but started the rebuild before I got around to it.

[Snitty]

remember, with lube, you can seal the wires.... but you cannot seal the rotor contacts

[MudderChuck]

I´ve waterproofed a few distributors. The best methode, seemed to be a fine bead of silicon sealer at every seam. The technique that seemed to work the best, was when the silicon was sandwhiched, between the rubber piece and part to be sealed. A dab on the drain hole in the bottom of the distributor, a small bead around where the cap seals and where the cables enter. A small bead around the plug cable distributor towers and on the plugs themselves, about half way down. Where the wire goes into the boot, I also sealed with a small bead of silicon. Same with the coil, high voltage cable.
The down side is when you have a problem, and want to troubleshoot. Cleanup before reaplying, the silicon can be a pain.
I´ve completely submerged, distributors, sealed with this methode and had no loss of spark.
Next best methode is just to seal the distributor with silcon sealer and spary all the boots, with a silicon spray, for rubber (rubber softener/conditioner). Soft cables and boots seal better.
Never had much trouble with, a non vented distributor cap. Vented caps, always seemed to corrode faster than none vented caps anyway. On the 4.0 motor the Ford non- vented cap, seems to last longer than the OEM type jeep vented cap (and was a buck or two cheaper)..

[Craig]

I sealed the cap of my distributor with silicone. My distributor has a breather vent in the top. I pulled the cap off the vent and ran a breather line into my airbox. Never had a problem since.

[Inspector-Gadget]

Hi Deerhunter,

To directly answer your question, I think your distributor, or distributor cap, should be vented for the reason that firemanharry stated.

But, Deerhunter, since you stated that you think the problem is caused by cooling fan water spray, not immersion, I wonder if your distributor drowning problem might be more simply solved by fabricating a spray shield to mount between the distributor and cooling fan?.

If a spray shield worked, you would not have to deal with any "sticky silicon" problems when servicing the distributor somewhere down the road.

Regards,

Gadget

[firemanharry]

The only reason I never got my distributor under water was because it died before I got there.