The mysterious case of the rev counter.

My car has a rev counter, fitted from new. Runs off the coil neg.
Never seemed that accurate although as I (still) haven't driven the car yet, hadn't paid too much attention.

I'm sitting in the car today running the engine, hoping I've got to the end of the problems and can take it out for a run, but no. As I rev up to about 2,000 there's a bad misfire. Shakes the engine. If I try to rev through it, I can and it clears, but while it's missing it's pretty bad.

Then I notice that the rev counter stops rising at the point where the misfire starts, and when it gets bad the needle goes all the way back to zero.
I tried disconnecting the rev counter in case it's somehow causing a problem, no change.

Misfires hot or cold.
Timing is OK plugs are new, firing order is right, points gap is OK. Original coil & ballast, the coil impedance (do I mean that?) is OK for the ballast. Fuel pressure is correct, I set the wet fuel level. Still on the old carb.

So, is the rev counter trying to tell me something about the ignition, or is it just faulty?

Ivor

Thanks. Hopefully I can find some points in my local shop without having to ship them 5,000 miles.

Did ask at the shop where he's very good at finding cross-references for old parts - he has a lot of parts books and doesn't rely on the computer. However, no joy for the 327, perhaps not surprising. I'll take the points off the car so we can look for a match.

Probably not hard to find a condenser that will fit on the baseplate, but how do I measure the capacitance. Rather than get into that, I think I'll fit a modern coil and ballast, then I can use a standard new condenser in the 0.25-0.29 microfarad range.

Ivor

Thankyou for that thought. I changed the coil and ballast today, no better, so it begins to look as if the points/condenser may be at fault. I did notice that the inside of the dizzie - yes, Autolite - is rather oily.

That would be Ford US, I presume.

Was thinking of a Lumenition, if they have a kit that will fit.
Could you possibly point me at a suitable Pertronix? I looked on eBay US but I'm not seeing anything.

The battery is earthed to the engine, so no earthing problems as far as the ignition is concerned.

Btw, another odd symptom I noticed when trying to check the timing with my light - the light has an inductive pickup that goes on No 1 lead, can also read rpm. After a while I notice that the rpm count had halved. Very odd.

This is my first car since 1983 that has a full-time fan. Very hard keeping the timing light cables away from the blades. If it eats my fingers one day, I won't be too surprised.

Ivor

Thanks.
Summit only list for the Delco.
JEGS is a bit harder to search, but in its 5 pages of Pertronix, doesn't have what I need.
I emailed Summit to ask if they have a kit.

Ivor

I've gone on the Petronix site and got help from them (customer service rep?) to find a correct number.

I also had a problem a long time ago and found that after taking the points and condenser out and re-installing them it was good. Maybe a wire was shorting or something. I would think that if the condenser and points are good make sure the gap is not too wide like maybe .016 max. Also check the top of the coil for carbon tracking and have a look at it at night to see if it leaks.