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My armchair GUESS would be to get the distributor on a Sun distributor machine operated by someone who knows how to use it...

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That's what my guess was as well: something wrong with the distributor. I'll ask around here to see if anyone knows of a local place to send it. Are there any places you recommend? I don't mind sending it out to someone who knows what they are doing.

-Kevin

Compression looks very good. That engine should run very smoothly once you get the ignition and carburetion working properly. It could have a sticky valve or weak spring, and a vacuum leak at the intake manifold or the wiper vacuum connection or the vacuum advance unit, or any other vacuum operated accessories, if present, are possibilities.

At the far end of the spectrum might be a leak IN the intake manifold?

IN the intake manifold??? Yes.

My mate with a '37 Super Eight(320c.i.) had this happen and I've seen it happen to a couple of other Packards.

Because the exhaust maniold is "coupled" to the intake manifold it resulted in hot exhaust gasses burning through the walls of the intake manifold. Solution was to sleeve, ie "force fit" some stainless stell tubing, I think it was 1&1/2", memories of 15 years ago mend to fade.

Holes were blown through the walls of both barrels of the intake manifold, pic's below

IIRC, Ken P had a similar problem, with his '37 115 or 120.



































?

Also not sure if the 37 had a resistor in the ignition rotor, if so then you shouldn't run resistor plug wires, if you are.

You can also check the ohms on each plug wire and see if one or more of them is way off compared to the others.

I have a multimeter that can also check rpm, dwell and a myriad of other automotive items.

But as other said, check for vacuum leaks as well. A can of brake cleaner, carb cleaner or staring fluid can help to find those on the intake.

Weak coil, dirty points, point gap, all the usual ignition gremlins. If the timing is moving around a bit, couldn't be distro wobble.





Also plug cross firing.

TxGoat - I had previously sprayed brake cleaner around various areas to see if RPMs changed at all and I didn't notice any change. I'll go through it again and check to see if that's still the case. I did not check the wipers though. One wiper works when I turn it on, the other doesn't. I'm not sure how similar a '37 is to the '51-56 wipers, but I would assume one not working is a linkage problem. I can't see anything under the dash with the additional wiring and A/C equipment, so if it's a linkage problem that's the way it's going to stay.

Oxstatman - Now that is very interesting. I never would've guessed that could be the case. Nothing was noted during the reassembly of the engine (I wasn't present for most of this last reassembly) but I supposed it would be easy enough to check by taking the carb off.

Kev - No resistor on my rotor. I don't recall what kind of plug wires I used, I'll have to see if it's stamped on the wire insulation. I do need to check the resistance on the wires. I don't think my multimeter does rpm and dwell, but I'll have to double check that. I'll go through all the system again to see if something changed....points burned or out of spec, etc. I set it all correctly the first time but it's possible it's off now.

My timing gun is weird. When I put the clamp around the plug wire it ends up shooting the light all over the place. If I put the clamp directly on the bare connection between the wire and spark plug then it reads the timing correctly. I was apparently way too high, and I backed it down within range. But still a definite steady miss.

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Yeah, easy to check. The problem wasn't noticed initially, so easy to overloook.

If the intake manifold is leaking into the exhaust heat jacket that surrounds it below the carburetor flange, spraying solvent may not affect it.

Another possibility is that the check valve at the bottom of the intake manifold drain pipe (if present) may not be sealing tight and allowing an air leak.

A dead miss on one cylinder on a engine that shows good on a compression check [usually] points to an ignition issue.

An exhaust valve that seats well when the engine is cold can begin to leak enough to cause a miss as the engine warms up if the tappet clearance is too small. That might allow a good compression check reading, yet still have a valve-related miss once the engine is running. An exhaust valve that is not seating fully will get very hot very quickly and expand, thus aggravating a low clearance problem.

My car recently developed a miss at idle and low speeds. I figured I had a burned valve or cracked seat. In fact, one exhaust valve was set too tight. Adding a few thousandths clearance corrected the problem, and it has not re-occurred. I don't know how the valve clearance got tighter, but it did. Perhaps when the valves were adjusted, there was carbon on the valve face and seat, and me driving the car frequently burned off the carbon, thus reducing the tappet clearance enough to make the valve overheat.

**If your car has a vacuum booster built into the fuel pump, it could have a leaking diaphragm, which could allow air and possibly crankcase oil into the intake manifold. This would probably affect 2 or four of the cylinders, and could cause missing and fouled plugs.

I could never use an inductive timing light. I had packard 440 plug wires (non-resistor) and the induction light would start firing before it was even connected to a wire.

I ended up using an old inline, neon style light timing light.

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I bought an old neon style timing light used, it arrived dead. So I'm a little gun shy about trying again. I haven't dug into it to see if it's something I can fix or not. But it would probably work better.

I checked the spark wires I used and they are Belden (NAPA) 7mm. I don't think they are resistance type.