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cap tick

skog

NAXJA Forum User
my distrubatator cap ticks. i put a screw driver on it and the tick was definatly comming from there. any reason this would happen. any way to fix it?

skog
 
Distr. ticking can only be caused by a few things:
1. rotor not seated on shaft properly, or damaged so tip is touching contacts in cap
2. cap not seated properly on dist. body, so cap is misaligned, causing contact with rotor.
3. distributor shaft bushings WORN, so shaft is wobbling around inside distr. housing, and rotor is hitting contacts in cap.

Five minutes with the cap and rotor off ought to give you an accurate diagnosis..................
 
As posted above -- take a look and see what you have...

Dont forget that the distributor drives the oil-pump and that that you could be hearing stuff from there or the cam-gear --

One thing to think about is the period of the click and how it related to the enigine (eg: is the tick once per engine rev, once every-other engine rev, 7-times each rev, etc...)

It could also be nothing more than a carbon-track or other spark-robbing path flashing over
 
it sound like a nervous person tapping a finger. it is either once a rev or once every other rev. I am not real sure what i am doing so could some one walk me through on a diagnosis. thanks

skog
 
Here's something to start with.

One of the first things you should do is to open the hood and run the engine in the dark. If there's a stray spark it will show. A bad plug wire or a carbon track on the cap can do this and make a ticking noise. Fix that before going any further.

Take off the cap and look carefully at its inside surface. It should be shiny and smooth. Any cracks or carbon tracks = a bad cap. Look at the posts inside the cap, and at the tip of the rotor. Normally, the rotor should come very close to the posts, but not touch them, and the surface of each post will look pitted and a little scorched after a while. So will the part of the rotor that passes by the posts. If you see a shiny spot on one post or the outside edge of the rotor, you can suspect that it is hitting.

If you grasp the distributor shaft, it should not be possible to wiggle it sideways at all. A little up-down play is all right, but if it goes sideways it's worn.

You should also check the little carbon button in the center of the cap (inside) to see if it's still there. It should contact the spring on top of the rotor. If it is broken or lost, the car might still run, but the spring tip might be clicking against the cap as it turns.
 
ok so i took the cap off today. there are no shiney spots on the cantacts. the blade part that spins has a little bit of a shiney edge but not much. about 1/2" above the bottom of the cap the are some rub marks but i dont see anything that could rub it so it may be from the sasting process. the rotor has some side to side play about 1mm. the carbon button is still there but it has a crack running down the middle. what so you thing the problem is. how hard is it going to be to fix this and how much should it cost?
 
Take the rotor off the shaft (it pulls straight off). Grab the shaft and try to move it around RADIALLY. It should not move at all.

You definitely need a new rotor. IT should cost about $8 at any decent auto parts store. A new cap would not hurt while you are at it. They cost about $12.

Check the shaft and get back to us.
 
the shaft has play but not very much. it feels like it is moving .5 mm or so. very little play but it does have some.
 
Sounds like worn bushings to me. Maybe it's time to take the distributor out and over to a auto machine shop, and have them evaluate if the bushings are shot.

If so, buy a rrebuilt distributor.

If you do take the distributor out, be sure to do two things:
1. Note the radial location of the rotor relative to the engine block
2. Make a reference mark on the distributor base near where it joins the engine block. Make a corresponding mark adjacent to that spot on the block proper, to allow easy realignment when reinstalling.
 
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