I'm having a strange problem with the 86 brat and could use some advise.

 

 

Has anyone experienced the engine appearing to rev(from 3 to 5rpm, according to the tach) and the engine acting all jumpy?

 

I at first thought it was the clutch, but on steep climbs i can't get it to do it, and I'll also see and feel it happening with the clutch pedal depressed, so the clutch would be out of the picture.

 

It will usually start after the car is at temp. I don't have to be giving it alot of gas, sometimes it will do it while coasting. The tach starts to jump up, and the car pulses, sort of like a slipping clutch would feel.

 

What feeds the signal to the tach? Is it just a cable with a sensor on the cam? Is it electronic? Is there a brain in an 86 GL that would control engine idle and increase it without gas pedal involvement?

 

I can also hear a winding noise when the tach jumps up.

 

So far I've replaced the alternator, coil, and gas filter (lower).

 

Anyone have any suggestions or insight?

 

Thanks for the help

Sounds to me if I read your post right that the tach is jumping but the engine revs aren't. Probably a distibutor that is on its way out. Mine did that for a while, then fixed itself for a year then completely went.

Does the tach connect to the distributor?

 

I had another strange thing happen, The metal piece that is on the top of the rotor came off and I found it and the rivet that holds it on, laying in the distributor.

 

Could I have missed a piece? Could this cause a jump in tach rpm indication?

 

Sounds to me if I read your post right that the tach is jumping but the engine revs aren't. Probably a distibutor that is on its way out. Mine did that for a while, then fixed itself for a year then completely went.

Yes the tach comes from the disto area. My guess is it is just going.

The tach comes off the ignition coil, which is controlled by the distributor. See if there is play in the distributor shaft - thats probably the problem. If so, you'll need to get the bushings done in it or find a second hand distributor.

Besides play in the distributor shaft bushing make sure all your ignition wires are on good and tight.

The tach comes off the ignition coil, which is controlled by the distributor. See if there is play in the distributor shaft - thats probably the problem. If so, you'll need to get the bushings done in it or find a second hand distributor.

 

I know some BRATS in 86 had a non rebuildable one (mine was like that).