Calgary Jeep Association

4x4 Related Groups => Tech Talk => Topic started by: TJ54 on May 24, 2005, 08:29:09 PM

Title: 2.5 distributor
Post by: TJ54 on May 24, 2005, 08:29:09 PM
On my 4 banger TJ the distributer cap has a vent on the top, Can I plug the hole, It has let water in several times now.
I have never seen a vent on a cap before and I don't know why it is there. I could run a vent line to somewhere dry, but it would be easier to plug it.
TIA

Ian
Title: Dist cap
Post by: henry on May 24, 2005, 09:44:45 PM
Ian,

Why don't you get off your wallet and buy a new distributor cap!! :lol:  :lol: That way, you will know for sure and keep your old cap as a spare.

Darren
Title: 2.5 distributor
Post by: TJ54 on May 25, 2005, 05:29:54 PM
Okay. So I stopped off and picked up a new cap from NAPA. It also has a vent in it, although it was a slightly different design so it should not let in as much moisture,

But I still don't understand why there is a vent in the cap  :?
The guys at the store did not know either, the best guess was to stop condensation.
I may just block off the vent and see what happens,. As I have had to remove and dry out the cap several times on  the trail now.
Title: 2.5 distributor
Post by: TJ54 on May 25, 2005, 05:51:30 PM
Here is a pic of the new cap, you can see the vent on the top of the cap. I took off the little rubber cap that goes on the vent. It is in the pic too
(http://www3.telus.net/public/imh/cap.JPG)
Title: 2.5 distributor
Post by: youngen18 on May 25, 2005, 06:52:30 PM
your not the only one.  whos havin issue with that vent  :(

kinda sucks when this happens on the trails. Keep us updated if u find a good fix for it :)
Title: 2.5 distributor
Post by: hatjpr on May 31, 2005, 10:42:43 PM
could you attach a hose and run it to a higher location?
Title: 2.5 distributor
Post by: Elsifer on June 01, 2005, 11:03:50 AM
I'm no mechanic, but I believe the vent is for allowing air to escape. When the vehicle is cold, and the rotor inside is not spinning, the air inside the cap is cool, thus dense. When the rotor begins to spin, the air warms up, becomes less dense, and expands! So the vent is there to allow for temperature differential, and other physics related actions. Not to mention, electrical arcing causes heat, and gases, and they need to be vented.

Though, if I recall, there was an article on distributors in a recent Jp or OffRoad mags. I'll take a look tonight.
Title: 2.5 distributor
Post by: henry on June 03, 2005, 05:19:38 PM
Quote from: "Elsifer"
I'm no mechanic, but I believe the vent is for allowing air to escape. When the vehicle is cold, and the rotor inside is not spinning, the air inside the cap is cool, thus dense. When the rotor begins to spin, the air warms up, becomes less dense, and expands! So the vent is there to allow for temperature differential, and other physics related actions. Not to mention, electrical arcing causes heat, and gases, and they need to be vented.

Though, if I recall, there was an article on distributors in a recent Jp or OffRoad mags. I'll take a look tonight.


Absolutely right Chris, and Ian, you should ghetto-fab up some kind of whiz-bang vent hose for your cap. 8)