Hello All,

This is my first post to the forum, in search of a solution to a persistent problem with the way my engine runs. I bought a 67 valiant 100 in June from the original owner. I believe the only option ordered with this car was an AM radio, no power brakes, steering, or AC. Aside from the paint, the car is in really nice shape in and out. It had been garaged in the 80's and was only driven sparsely since. The service records indicated that the fuel pump and exhaust manifold were replaced in 2011. According to the PO the carb was also rebuilt

Upon getting it home, I changed the oil and coolant as a matter of course. I noticed that the engine would rhythmically chug and hiccup when idling, but runs great under acceleration. The valves are quiet.

I replaced the ancient plug wires, ignition coil, plugs, points, cap and rotor. New air filter too. Next I set the dwell and checked the timing (0 degrees TDC). I also adjusted the carburetor and checked the 2 vacuum hoses. PCV valve rattles like it should. The alternator was replaced because the bearings sounded horrible. Ignition wiring seems good and tight throughout and the battery is only a few years old. Voltage output is around 13.8V. I have probably driven 1000 miles, mostly city, but I did drive 150 miles nonstop on the highway.

Anyway, I am a 20 year old college student so taking it to a shop is out of the question and I also enjoy this stuff. I am curious to what may be the culprit.

Regards,

Mick

Put a vacuum gauge on it and look for steady vs. bouncy needle at idle.
Check for vacuum leaks at the carb base and between manifolds and head.

Adjust the valves - 'quiet' valves could be too tight.
Check for broken springs and engine sludge content while you have the cover off.

Take the carb off, disassemble, soak, reassemble with a kit.
If it sat that much there could be varnish plugging up internal passages.
'According to the PO' doesn't always hold any weight - assume nothing.
Besides, with modern fuel blends, it doesn't take long at all.

Did you check for sticking advance weights while replacing the points?
Give it a little more base timing for extra pep.
Collect parts for your choice of electronic ignition upgrade.

This is by no means an exhaustive list, but it should keep you busy for a while.

These kind of projects make a good study course in themselves.
It gives you a good chance to learn how things work, making you a better mechanic and a better driver.

Welcome to the slanted world!

_________________
O==\=/==O

"A mechanic is Somebody."
- Jim Preston

One tip that you may find helpful is to get rid of the points ignition. The points made these days are cheap Chinese junk. A good electronic ignition will make the car way more reliable.

_________________
Leela: 1970 Dart 225 CID
Coulmn Shift TorqueFlite
7 1/4" Axle 2.76 Gears

Go ahead and save that weird car, the sedan, the 6 cylinder, the C-Body. If you want a big block musclecar and that's all you care about, your missing the point.

Oh, and pictures!
You can start your own Gallery thread, and there are instructions on how to add pix.
Show us what it looks like. That always helps the diagnostic process.

_________________
O==\=/==O

"A mechanic is Somebody."
- Jim Preston

Put a little more timing in it and adjust the valves.

_________________
Official Cookie and Mater Tormentor.

Okay,

Thanks for the support. I plan on adjusting the valves and replacing gasket. I also will be sure to do a carb rebuild and check all sources of vacuum leak. Will post pics as soon as I find the time. Thank you all