C-48 rod bearing checks

[ronm10]

I have a knock in my 50 Windsor. I think it is a rod bearing. So I am planning on pulling each cap and checking the clearance with plastigage. Does anyone know the spec that I should be looking for?

Thanks

Ron

[ronm10]

Next question. I checked the first 3 rod bearings and had the following clearance results. #6 - .0018 inch; #5 - .0018 inch; and #4 - .002 inches. The bearings all look very good with no wear other than number 4. #4 has two stripes around it like a grain of sand or something got in there. The stripes are about as wide as the mark made by a medium point pen.

Should I go back and use some shim stock to get the clearance down to .001 or so? And will the stripes on #4 bearing cause any harm?

Thanks,

Ron

[Guest]

Shim stock will make your clearance bigger not smaller. You could file the cap to maker the diameter smaller but do not do this. Many people did this in the old days and it workes pretty good. The problem comes when the next owner or you try to put new bearing shells in and forget that the rods are not round or don't take them and have them resized like everyone should every time. I cannot think that you could hear the difference in .0002" clearance.

[ronm10]

Just a little update. I went through all the rod bearings and had from .0018 to .0023 inch of clearance. I went looking for shim stock and found out none of the local auto stores carry it anymore. So in a conversation with my father, an old shadetree farm tractor mechanic, he mentioned that standard weight aluminum foil is about .001 inch. So armed with that info I put a strip of aluminum foil between each rod lower rod cap and the bearing, except for the #1 bearing which had the .0023 inch clearance. On #1 I put two strips of foil. Plastigage of each bearing came up just under .0015 inches clearance. I called it good and buttoned her up. She still has a slight knock until for a minute or so until she starts to worm but I think that is a wrist pin. I am not going to worry about it no more miles then she will see in a year. Now to find the oil pump gasket as mentioned in a seperate post and I think her fuild leaking will be solved.

Thanks to Jon for his good advice.

Ron