Just a thought, What if a person were to copper plate the saddles in the block to accept a good tin job prior to pouring babbit? Would this work? If so I think it would be a lot better than just mechanical retention by the anchor holes. Anyone tried this?

I suggest doing more checking, The cast iron block is not tinned. That is why they are peened while warm after pour to fit to the block. The caps would be tinned. There are good books out there that describe the differences between pouring babbitt into cast iron and cast steel like the caps. No I can't suggest one but have been around a few people that do babbitt and have picked up a few things.

I know they were not tinned from factory but can it be done? If so I think it would be worth the effort.

Since they are already locked in place as tight as any modern insert bearing, I am wondering - Not withstanding the fact that it is really a difficult undertaking to get cast iron to take copper plating under ideal circumstances, much less cast iron that has been oil soaked, what failure mode are you eliminating that would make it worth the effort?

No matter how elegant, a solution is no good if it is not associated with a problem.

Tinning grey cast iron is no problem as long as it's clean, done it may times and even T blocks.

Frank

You didn't tin it with copper. Which would be an electrolytic process...That was the question.

Frank

just reread your post with a different set of eyes...you're right of course...you can get cast iron to accept lead based tinning just fine.

Scott.
It doesn't need to be lead based, can be done with tin babbitt the same as the prep of main caps and connecting rods, I used babbitt to repair freeze cracks as well in grey cast for many years.

Thank you for that info.

Frank,
What do you use to tin cast iron? Your methods? I tried to tin and solder a cast iron neck to a radiator once but that didn't work out to well!

Scott,
I would like to have a full thrust bearing on the third main. Not just the cap half. I know it wasn't done like that at the factory but it would provide for a longer thrust bearing life. Besides that I just think its a great idea worth the effort. Whats your thoughts Frank?

Jason,
First of all I give cast iron a good cooking in a caustic hot tub, rinse that with plenty of water, grind, sand paper or a flapper wheel as well on your working area. I use a 1" propane torch to just warm up the area of tinning and wipe that with a brush with hydrochoric acid, don't breath the fumes as that will try to kill you, wipe with a wet rag, don't leave it to long to tin or it will go rusty, then with the torch bring to a temp on which you can melt a babbitt stick and tin with a flux brush and flux of your choice, I use a brand name of Bakers flux. Any tinned surface will oxidise with in a few hours and then give a poor bond for adding a pour so do your work as soon as possible, re-tin if it looks tarnished.

The question was can it be done, sure.
Do I bother? No, but have done them that way before but is time consuming and I just don't bother. Ford did and showed a couple of ways done back in the day from hot block pours and cold.
After a good cleaning and a 1/8" drill downwards in the anchor holes for babbitt to hock in, heat the block and mold at the bearing, pour and let it all cool with the mold left on, never had one yet shrink off the block.

As for making a whole thrust surface, yes it has been done before by cutting the block back a bit and adding a few anchor holes as well.

Frank, Thank you for taking the time to explain your process. Its very much appreciated

Copper is not a good backing or base for babbitt. Copper has a tendency to absorb a portion of the tin component and cause the bond to fail.

Frank: Thanks for sharing this information. I won't likely be pouring any bearings, but it is great to know how it can be done. All the best, jb