joe350

Just like the title says. I believe my rough idle may be, in part, caused by a bad distributor. Timing is a little funny, but not really that bad. With the EST wire unplugged it slowly retards from 6* BTDC at idle to about 5* BTDC as I increase throttle. Then it hits a certain RPM where it advances suddenly to 12*. Could this be causing my rough idle? Is the "inductive pickup" located inside this distributor or is it external? There does seem to be too much movement in the distributor but without a good one to check against it is difficult to tell. What should I look for?

Here's some pics. They are big and nasty I know, but at least theres plenty of detail:

joe350

Preliminary tests: When try to move the shaft up and down there definately is about 1mm of play there. Side to side it seems pretty stable. The bronze-ish circular piece (second picture, black arrow points to it) thats right under the rotor on the outside can rotate about 10* with minimal force. As I rotate the gear I seem to feel a slight resistance every quarter turn. I don't know what thats about or if its normal.

Vader

Put it in a small room by itself for about three days. If it starts chanting "Death to America" it's probably a bad distributor (and may explode).

1mm (0.040") axial play is not completely within specs, but I've seen them a lot worse and still running. There are shim kits available to correct this and get the play down to the recommended 0.015-0.020" (0.4-0.5mm). Instead of guessing at the amount of play, measure it with a feeler gauge:



And I cannot see photos or links, but am guessing that the "bronze-ish circular piece" to which you refer is the shroud for the pickup coil. This should not be moving. Is the distributor removed?

joe350

Yes, the distributor is out. It seems I have exceeded the data limit for geocities, thats why the pictures wont show.

I always thought the pickup coil was the piece that sits off to the side of the distributor (passenger side) and connects to the middle of a cap via a wire resembling a plug wire. Is this a different kind of coil? Forgive my ignorance but the distributor system is a weak point for me.

joe350

I have reduced the picture size so hopefully I'll stay below geocities' quota. I have also added a black arrow on the second pic to illustrate the "bronze-ish" piece that moves.

Vader

That's the pickup coil cover. If only the outer shell is moving, it's not a problem. If you observe the coil itself moving, that is a problem.

joe350

Thanks, as always I appreciate the help.