Inserts vs. Babbitt?

As far as pressure oiling, some use inserted rods and mains with dip oiling for the rods and the original oil slinger at the rear main. Pressure oiling isn't necessarily required. As for babbitt, Back in the day, there was diesel babbitt that could withstand compression ratios of 14 to 1 and higher.
 
For years rebuilders used inserts from a variety of sources. I used to have a list of the inserts and what vehicles they were from for different crank diameters but I might have lost it when the computer crashed a few years ago. I mention this because I wonder if the block work needed for inserts is different for the different inserts. If one needs new inserts what are the odds that they can be easily replaced?
 
Mike V. Florida said:
For years rebuilders used inserts from a variety of sources. I used to have a list of the inserts and what vehicles they were from for different crank diameters but I might have lost it when the computer crashed a few years ago. I mention this because I wonder if the block work needed for inserts is different for the different inserts. If one needs new inserts what are the odds that they can be easily replaced?
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The ones I used for the mains were 4-2965-cp you bored the engine 1.7705 that is the same as the new inserts. But you have to put in a new notch for the bearing tang.

I think there were 3 different bearings that used 1.7705 there were about 3 more that used a different size. So I guess your odds are about 50-50
 
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I have an old listing--A main bearings
international harvester, 1456sb --1.063 width, std shaft size 1.623, bore size1.7760
british leyland(rod bearing)4-2956cp, width .880, shaft1.6254, bore1.7705
onan (rod bearing)3180sp, width 1.00, shaft 1.6252, bore1.7505
standard motors (rod bearing)4-65290ra, width .690, shaft1.6250, bore1.770

I know the british leyland bearings are for early 60s mg midgets ---they wern't the most reliable bearings in their original application, they would crack in 1/2 in the midgets, the other bearings are all listed in my 1965 bearing catalouge ---so they are for at least 50 year old engines

The AER bearings list a bore size of 1.7705 ---so there is a good chance that a block set up for the british leyland, or std motors bearings could be easily modified to take the made for the "A" AER inserts
 
Doug Bruce , N.Y. 1-607- 849-3454 . ANYONE THAT KNOWS ABOUT INFO ON THIS ENGINE???? 1932 /33/34 Ford block 4 banger...Someone said its a Engine for time trials [one shot]. Aluminum front timing cover with oil pump ,, DOUBLE piston rods ,,, 4 bolt bearing caps ,, has headers , Mallory Dual point dist. and Mallory coil...there is a hole in the fly wheel housing so you can set the timing and a weird ****** he thinks might be for a Lincoln Zephyr/// anyone into early speed stuff please give him a call...thanks ...thanks
 
daveymc29 said:
So, now that I have to make a choice on the rebuild of my engine, which way to go? Inserts and full oiling or just stick with the babbitt and hope that outlasts me? Any reasoned thinking out there on this subject?
Thanks in advance, Daveymc29
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Don't forget Thick bacon slices. During the depression a farmer needed new bearings, could not afford anything, so used very thick bacon slabs and got his car running again. Says a lot about resourcefulness. As his engine warmed up, I wonder if it smelled like bacon was cooking.
 
FrankWest said:
Don't forget Thick bacon slices. During the depression a farmer needed new bearings, could not afford anything, so used very thick bacon slabs and got his car running again. Says a lot about resourcefulness.
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Geez this one just came out of the mothballs!! :eek:


Personally I cannot imagine that story about bacon being anything more than an old wives' tale as it would not take very long for a strip of bacon to be compressed enough to squeeze it out of a bearing journal. Even leather did not last more than a few miles or so. Definitely not saying that either did not get tried, but even babbitt will get pounded out, and a soft material such as leather or bacon would not be long for this world in such an application.
 
I'd like to ask one question and make one statement ;
There have been billions of cars made world wide since about the 1940's. How many of them used White Metal???
I used shells in the engines I built for outback touring. Only one has pressure feed to a bearing (the middle main at 25 psi). All other bearings are lubricated as Henry did it and I have not had a bearing failure yet. These motors work hard as I tow the camper (about a ton) at 50 mph all day every day for weeks on end. Pressure oiling is NOT neccessary with shell bearings. I do run an oil filter though.
 
So.... pressurising the center main is to stop the babbit being whipped out due to the, shall we say.... unsmoothness of the crank (?).

My next question, here it comes.

Does this not happen with inserts?
 
BRENT in 10-uh-C said:
Geez this one just came out of the mothballs!! :eek:


Personally I cannot imagine that story about bacon being anything more than an old wives' tale as it would not take very long for a strip of bacon to be compressed enough to squeeze it out of a bearing journal. Even leather did not last more than a few miles or so. Definitely not saying that either did not get tried, but even babbitt will get pounded out, and a soft material such as leather or bacon would not be long for this world in such an application.
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No one said the how successful bacon was for bearings, just that some desperate farmer tried it. People try all shorts of things in a pinch!
 
updraught said:
So.... pressurising the center main is to stop the babbit being whipped out due to the, shall we say.... unsmoothness of the crank (?).

My next question, here it comes.

Does this not happen with inserts?
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If any bearing is going to fail in a Model A, it is the middle main bearing. My motors all run a counterbalanced crankshaft and run smooth enough. The last thing I want is for a bearing to fail out the back of Timbucktoo on a rainy day. Does it happen with inserts? I don't know and I don't want to be the one to find out!
 
Adding counterweights or buying a counterweighted crankshaft is the best thing you cab do to extend the life of the main bearings. The faster the engine runs, the more important counterweights become.
 
Kurt in NJ said:
from a 1935 chilton
Audburn lists bronze backed main bearings---renewable from below
Cadillac --bronze backed --renewable from below---by 1930 steel backed for some
Chyrsler 75, 28-29, bronze backed, pull engine, but no hand fitting or reaming
Durant 1929 --pull engine but no fitting or reaming
Grahm paige --renewable from below

Oldsmobile f33 1933 --mains, steel backed, renewable from below, rods removable babbitt lined steel shells

Nash 1220,(1934) mains, steel backed, renewable from below, rods, removeable steel backed babbitt lined shells

Hupmobile, 6 cylinder 1934, mains bronze backed, removable from below, rods, removable steel backed babbitt

I remember taking apart a Franklin engine and it had a form of inserts, it was before 1928, to me they seemed like solid babbitt ---but they had the look like they required fitting , the cars that list "renewable from below" to me indicate modern style precision fitted bearing inserts, but although I didn't look up all the cars it seems that modern type steel backed precision inserts appeared in 1933- 1934 in several cars for rods, mains before them
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Dodge Brothers were inserts from day one.
Vern
 
Here's the thing though... When an insert bearing wears, it goes through the very thin layer of bearing material, now what is the crank running in. typically, first a thin layer of bronze, then the steel backing. Steel on steel, not so good for the crank. It then seizes, and turns the insert in the block, not so good for the block.

When a babbit bearing wears that same amount, the crank is still running in, well, babbit. No crank seizing, so no real crank or block damage.

Both were fine until massive wear occured, but then the difference shows up. So, why the switch to inserts for all the mfgs? Easy. No hand fitting required. Cheaper mfg process. It can all be automated, saving labor costs, but more importantly, requiring a lower caliber labor force, which means even lower yet labor costs. Like most things, it is all about $$.

In an engine that is well maintained, with regular oil changes, either should perform well. If not well maintained, you better not let those bearings get too worn before replacing inserts, or major damage can result.

Probably in model A heyday times, babbit had an edge, but not any longer. Just what I think, no facts have been intentionally harmed in this writing.
 
With well done babbitt bearings is there any rule of thumb as to when you should check them for clearance. Assuming they have not been abused by lugging and oil changed about every 500 miles.
 
Good Morning all...If your engine is running nice and quiet and you change your oil every 500 miles...and you check the torque on your head once a year...and you check the out going oil with a little strainer...and there are no bits of metal coming out with the oil...then leave the engine alone, drive it gently...enjoy it and it will last a long time.


When rebuilding time comes, find a good local rebuilder or go to the major suppliers who all offer rebuilt engines on an exchange basis. If you do not belong to a local club, then contact a couple at the time you need an engine rebuilt. They will know who does Babbitt and or Inserts with a high degree of quality. Ernie in Arizona
 
I agree with Corley. Tearing my engine down I found a shot center main, cracked rear main and one of the rods missing a large chunk of babbit. The crank was still perfectly fine and only needed polishing, kept it at .010 under. The babbit did a great job of saving the crank.

Something tells me if I had inserts things would have been worse. Just my opinion of course.
 
Is it possible to drop the rear main bearing cap to adjust shims in a B engine with a BB counterweighted crankshaft or is it necessary to pull the engine?
 
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