48 Dodge six engine problems, I think. Test figures for you.

I think this is a valid question for many makes of the era,

but the sick patient in question is a 1946 Dodge flathead.

When started cold (seventy degrees or so) it vibrates severely,

and will hardly accelerate from idle.

After warming up it idles smoothly, but giving it some--

a little-throttle the vibration recurs, and further throttle

usually sounds pretty good. No load, remember.

Driving, once warmed up, it is OK up to about 40, with OK

power, when the vibration gets pretty bad. You have to hold

down on the shift lever because it is rattling and carrying on

something fierce. Fifty-five is out of the question.

Too much vibration.

Here are the figures for compression tests

and vacuum on warm engine.

Dry cylinder After adding uniform amount of oil

60 100

55 87

60 105

70 75

55 105

vacuum at idle almost nonexistent.

at revved speed, 15-20

My bud says he can feel the fluid drive unit vibrating as if it were

out of balance somehow. Fluid level was fine.

Q: Would these test readings support the conclusion that

the vibration is caused by the worn-out engine?

Q2: What else, if not nearly conclusively the engine, could cause the vibration and poor power? I suppose the poor power could be so explained.

Compression is supposed to be 125 - 135 PSI on your engine. So you have some badly worn rings and valves. How is the oil pressure? Any raps or knocks hot or cold? How many miles? You might get away with a ring and valve job or overhaul but most likely your engine is ready for a rebuild.

This is not a real big deal on a flathead six but it's not cheap either. You can buy all the parts as a package deal from Kanter or Bernbaum for under $1000 and probably another $1000 for the machine shop. That is if you take it out of the car.

You definitely have some leaking valves and most likely worn rings, but I doubt this is the primary cause of either the vibration or the non-existent vacuum at idle. The vibration could be worn motor mounts in conjunction with the poor compression. The low vacuum at idle indicates a possible timing chain problem.

Compression variations and lack of raised compression when oil is added indicate leaking valves on those cylinders. However, the overall low compression might be due to the timing chain being badly worn. It may be worth investigating the chain, pulling the head, and checking for bore wear before a final decision is made. It's possible a new chain/sprockets and a ring and valve job might be all that's required.