sintered bronze main bearings vs alum steel

[fabr]

Question comes down to..for instance if you were to buy .010 sheet...alum..brass..bronze and form your own bearings by pressing with the crankshaft to form..with the proper lube holes and locking clip....would that not be what is needed and work?

next question is....how hardened should that material be? and which material?

I may be wrong but I see no way that would work.

[modok]

.010 thickness, might work for a .400 diameter shaft

he invented k-line

[dtoots1]

I hope you all did refer to my post of 4/20/2024 @ 11;36am to see just what my problem consists of...ie...need for main bearings for 2 cylinder john deere engine...no longer currently available...at least not within the last 3 years...available for the connecting rods but not mains...3 different models all take same mains up to .030...

and wondering just how to make own...
dwilliams post mentions that he made mains for an antique engine from scratch using...aluminum bar stock and did not have bearings to see and follow..

So you TECH guys could maybe answer...these engines top out at barely 2000rpm ...so why not use aluminum, brass, bronze or similar to make mains from scratch.???? These machines date from the 50s and 60s and are still in use and useful...

Am not tech oriented but seriously need some answers or solutions...

[fabr]

Packard v8 gave some good advice that I would pursue first. Then if nothing could be made to work I would not hesitate to machine from aluminum or brass bar stock. It would not be difficult to add eccentricity into it either.

[dtoots1]

Just another thought on these mains....would it be possible to reline the existing mains...these were scratched and maybe scored from engine coolant leaking thru a cracked cylinder???...plate w/zinc or brass maybe..though not sure plating would fill? or quicker easier to machine new?

Thoughts?

[fabr]

Machine new.

[modok]

I'm not clear on what type of bearings we are discussing.
Aluminum, bronze, steel, babbit? Split shell or full circle? Thrust faces or no?
If you had a part number from a major bearing manufacturer we could look it up, and that might help, or not.
Many things can be done, although, it depends what you are working with

[Sodbuster]

This may be the worst idea/suggestion ever, but if worn pistons can be built up with Line 2 Line coating, could the old bearings be similarly coated to renew the wear surface ??

[dtoots1]

Simple suggestion...is just pull up main bearings on internet for jd420 crawler..same bearings are used in 430 440 crawlers...since am not sure how to post pics on this site..i can get some dimensions but not all...usually they list crank dimensions for the bearings....i did mention these are crank bearings for 2 cylinder engines from the 50s and 60s...i will try and get the numbers shown by John Deere...appears part # AM3168T and AM3170T..dims 2.368"..(.030) under

These bearings are steel shells lined with babitt metal....can they not be relined ? and finished to proper size?

[dtoots1]

ANYONE>>>

Biggest question is....how much would the cost be to make a set? or 2 if cost effective to do multiples....seems the rear main is also a thrust bearing....so assume why it has side overhangs??? front one is simply curved flat for around the crank...unfortunately my brother-in-law sold his CNC shop or would get him to do it.

[modok]

Thank you.
The pictures I am seeing are all a split tri-metal bearing, basically the same as used in most engines in mid 20th century.
Unfortunately this type is not an easy thing to make from scratch or fix, and is not resizable. (once the top layer is worn away it's mostly done)
I have never heard of them being built-up again, although, not saying it's impossible, it's just not practical to find out when you can buy a new one for pocket change.

My first thought would be..... adapting a bearing from a different application and using separate thrust washers instead of the thrust flanges.
That could have the potential to be a good long term solution and even work better too.
I am sure it is possible to make a bearing from scratch one way or another, but it's usually not as good long a term solution, VS using a mass produced part.

While automotive machinists do not manufacture bearings, we do have the ability to make crankshafts larger or smaller, and make bearing housings larger or smaller, thus can adapt a bearing from one app to fit another, and modify bearings.
I remember the old air compressor they discontinued the bearings on us....I think we used buick rod bearings stacked side by side in each rod. It ran smoother than ever until the head fell apart and wrecked it 7 years later.

[modok]

google Clevite MS319p, look for an odd set until they do another run