Guest Hockeye Posted October 16, 2006 Share Posted October 16, 2006 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 oil60 10055 8760 10570 7555 105vacuum at idle almost nonexistent.at revved speed, 15-20My bud says he can feel the fluid drive unit vibrating as if it were out of balance somehow. Fluid level was fine.Carb has not been rebuilt or cleaned up.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. Link to comment Share on other sites More sharing options...
Mark Shaw Posted October 17, 2006 Share Posted October 17, 2006 Check your ignition & timing first. Sounds like the vacuum advance diaphragm may have a hole in it. Link to comment Share on other sites More sharing options...
Guest Hockeye Posted October 17, 2006 Share Posted October 17, 2006 Will do that. Can't one easily get the vacuum advance unit from NAPA or such? Steve Link to comment Share on other sites More sharing options...
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