VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1929-1932 194 engine question

Now I am just curious mind you,

the engine in question a straight 6 194 in a '32 BA

original engine


Is it AT ALL possible to change out rods from under the engine with the oil pan off without pulling the head. I ask becouse i have a worn babbit bearing on the #3 rod from the front. No other rods are like this. I assume that this is from PAST monkyings from someone that didnt know how to adjust a rod and in the mean time, knocked this babbit egg shaped. I would like to know if pulling the piston and changing rod is AT ALL possible to do from the bottom of the engine. I've had this pan off before but like everything else, i forget what kind of clearance is going on in there.

Thanks for responces ahead of time

I guess it is possible, however you will have a hard time getting the piston back in from the bottom. How will you compress the rings to put it in from the bottom.

The safe way is to remove the head and do it right.

The old timers claimed to be able to replace the rods from the bottom. #2 & #5 are easy as there is nothing (except the crankshaft) in the way. The rest supposedly can be pulled down to allow removing the pin while leaving the rings in the cylinder. Back off the bolt on the rod, slide out the pin, install the new rod, slide in the pin (might be a little tricky to align it), clamp with bolt and push back into position. If the oil ring is exposed then you have a problem.

I worked at a garage in the fifty's and it was common to have one crank journal turned from the bottom (mostly by used car dealers) after pulling the pan. The gentleman that done our work had a crankshaft business along with a portable grinder. As Chipper said there were certain rods and pistons that could be removed and replaced otherwise we had to pull the head. He had a special ring compressor to reinstall the rod and piston. It wasn't unususl to replace just the rods. There was also certain journals he couldn't turn because of clearence problems with the machine. I guess I would qualify as one of those "OLD TIMERS"

So what do ya think about the #3 rod....would it be in the way of something?

Im pretty convenced i have worn babit trouble in the rod. I was told by a couple long time mechanics that a good chance it is just the rod bad and not the crank pin. It makes sence. Soft babit, HARD crank.....whadya think?

Replacing a rod from the bottom was easier on a 216-235 because of the design of the piston. They had was was called a slipper skirt piston. The skirt was long on the sides of the engine and cut up higher in the front and rear. This allowed the piston to be rotated 1/4 turn and the longer part of the skirt brought down between the carnkshaft counter weights. The 1929-1936 skirt is long and solid making it more difficult to bring the piston down far enough to slide out the wrist pin. On some of the cylinders of a 216 it was necessary to break out a little chunk of the skirt to get the piston down far enough.

As far as the condition of the crank pin goes, if the engine was operated any length of time with the rod loose or the babbit burnt out (that being more common on a 1932) the crankpin will be damaged and that makes it difficult to fit a new rod....or to prevent the rod from loosening up again. It you can feel a raised grove in the center of the crank pin on one area the shaft is out-of-round.