VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1933-1936 1933 Questions

I have a 33 Master Sedan which I recently overhauled the engine. Engines runs great, but makes a sound similar to diesel engine when I accelerate, then goes away when engine levels out.
I also have a 33 Master Coupe which does the same.
It sounds like maybe in the area of the rods. Should I be concerned? Or is this normal?
Secondly, on the 33 Sedan, there is vibration in the car at 30-35 MPH, but smooths out at about 40-50 mph. I know my wheels are not perfectly straight, but in other ideas why this might happen?

33eagle

Rods could be too loose or main bearings.(also several other things)....I know its a lot of work but I would recheck the adjustment of both-following the shop manual method.And not by using Plastigauge.

Yes. it could destroy the beraings and crank shaft with continued use.

Vibration is like the noise-without being there to hear it (or feel it) its rather difficult to diagnosis.Does the vibration occur with the engine in neutral when brought up to that speed?

33 eagle :
There is one way to check if its a rod knocking. with the engine running manual rev the engine up if you hear the noise,,short out a sparkplug one at a time or pull the wire off. if you dont hear a knocking noise with the plug shorted as you rev it up but do when the plug is fireing that will be the rod making the knocking noise ..do all plugs this way ..and rework the shims on the rods.. good luck to you..
BE sure and do what chev nut said to do..

33 eagle
all so recheck your timing ,to see if its not a spark knock...dont drive it intill its running great,thats a nice car !!!!
if you dont have a shop manual let us know....

Along with the timing check, verify that the vacuum advance is working correctly.

Regarding the vibration on the sedan; The car does not vibrate in neutral, only traveling down the road around 30-35 MPH. The vibration is not severe but noticeable at this speed, and smooths out at higher speed. The vibration is not felt in steering, but the whole car.
Regarding the knock during acceleration on both cars; Both cars have fresh engines (less than 1000 miles), I really didn't think the rods should be loose at this point, but since the timing and advance seems to be true, I am going to perform the test carson suggested to see what results I get. This would be much easier than removing the stovebolts again to feel the bottoms of the rods.

Did the same fellow rebuild both engines? Also, the noise could possibly be a push rod hitting on the side of the push rod cover. On the vibration, it could be a tire out of balance. Did you get your engine balanced when it was rebuilt??

If you have more than one rod loose all of the cylinders with a loose rod would need to be disconnected.Removing one wire will eleminate only that cylinder.I doubt if one rod would make it sound like a diesel.Retarding the timing (temporaily) will also eleminate the noise if it is the rods (and eleminate the power).Try it as a test.

when you feel the vibration push the clutch in and let the engine come down to idle, if the vibration is still the same look at the drive line or tires, if it goes away look at engine problems and don't forget about the fan blade