Inserts vs. Babbitt?

[Kohnke Rebabbitting]

Dodge Brothers were inserts from day one.
Vern

Yes, they were inserts, but they were all babbitt lined with about .030 thousandths thick babbitt, with a standard main insert.

A babbitt bearing, is a babbit bearing. It is either a poured in rod babbitt bearing, or a poured in insert in a babbitt rod.

Same with mains, poured in block babbitt mains, or poured babbitt, in insert, in the mains.

Herm.

 

[Kohnke Rebabbitting]

What material is used to make an bearing insert?

Steel, Bronze, or solid Babbitt.

Herm.

 

[Kohnke Rebabbitting]

You mentioned white metal which is babbit on those 20 years ago. Has the technology changed for the ones sold now by the vendors for the
model A?

You can still get Babbitt lined Modern inserts.

Herm.

 

[Kohnke Rebabbitting]

Yeah, I believe that inserts have been made of different running surfaces. I just checked a flathead which looks to be copper inserts ('40 V12) .

If your bearings look like copper, that means that the outer layer of metal in the bearing is getting thin. The copper is put on before the babbitt layer, and there may be another layer on some before the babbitt. They have tried every combination.

Ford tried Copper-Lead, which didn't work out.

Herm.

 

[Kohnke Rebabbitting]

Studebaker was very early in the use of insert bearings.

Chevy 4's, 1912

Herm.

 

[Kohnke Rebabbitting]

My 1935 Chevy Standard coupe has babbit only on the piston rods. The Filling Station ,Chevrolet & GMC Reproduction parts house :Replace your worn out babbit rod with NEW "MODERN" style insert bearing. The key word here is "MODERN" Style. Babbit cost is $145.00 per rod..... 1916 to 1936 engines... $65.00 for inserts.... If babbit was as good as some say we would still have it today on our "MODERN" cars..

1953 Chevy rod, still was a Babbitt poured rod, and were from 1912, to 1953. Inserts for Chevy Rods, was only after 1953 at some point, and you had to send the rods to the factory, to get machined to fit. From 1912, through 1936, inserts were never available. The 216's were the only ones.

If babbitt cost was listed as 145.00, that would have to have been after, 1953.

Herm.

 

[Kohnke Rebabbitting]

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.

Diesel Marine, with 85% Tin, 10% Antiomony, and 5%Copper is used in, salt water and other marine, or hard to lubricate applications, as it has good wear qualities. It is made mostly for ship Drive shafts.

Most of all new engines came with Grade, No. 11

We use that, and Grade No. 2.

Ford Babbitt, we use sometimes, but it machines dusty.

Herm.

 

[Kohnke Rebabbitting]

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?

I would say yes, Mr. Mike.

Herm.

 

[Kohnke Rebabbitting]

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.

I don't think Bacon slices, were ever used, they would have a tendency to
" squeal ", as the crank turned.

But I know a slice of a leather belt was used to get the car home.

Herm.

 

[Kohnke Rebabbitting]

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?

On a Model A, it always will happen, with either, as that is the nature of the beast. It's the weight of the flywheel that puts pressure on the center main in the, block babbitt. If you can get more oil to it, the better. what really helps is a good counter balance job, and a lightened flywheel. The counter balance, and flywheel, when running, always tries to force the shaft to run in a straight line.

That is why, when you try to save the old babbitt, that is not in perfect Alignment, or a new babbitt job, like George Miller, explained about, you will have vibration, and can brake a crank.

Herm.

 

[Kohnke Rebabbitting]

Dodge Brothers were inserts from day one.
Vern

The inserts of the past, have nothing to do with how they are made today. They are all together different.

Herm.

 

[updraught]

Corley, thanks for the explanation.

I can see why an oil filter is important with inserts. Best to avoid them wearing out.

 

[BRENT in 10-uh-C]

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.

Yes, I probably agree with your comments inthe first paragraph, -and will abstain from agreeing with you on your second point. One of the issues that I have seen come through my shop is the aftermath of failed insert bearing conversions. The sales pitch that we all have heard was when a block is converted, it allows the hobbyist to change inserts in his own garage as opposed to depending on a machine shop for the repairs. By theory, this makes total sense however in real-world scenario, just as mentioned above, when the thin layer of babbitt as worn away, the crank is now riding on a much harder surface which creates friction and often times rolls a bearing. What tends to happen when a bearing spins or rolls inside of the main journal is the cap becomes distorted. This is generally not detectable by the human eye, and most home hobbyists do not have the metrology equipment needed to check this.


So when a cap has seen a bearing roll inside, it really needs to be ground and re-bored. Remember, this measurement needs to be within a tolerance of 0.0005" of perfect concentricity and in alignment from front to back. Generally speaking, this is beyond the capability of the home hobbyists, which means you are back to the machine shop anyway. And a FWIW, most of the time when a journal has a bearing spin, it causes the crank journal to become smaller than 0.030 undersized which means it has likely been ground under the original heat treating.


It should also be noted that the instances I have been involved with, the owner never actually heard the engine noise as the bearing clearance became excessive until they had the failure. I attribute this to a couple of things, -one being that the noise was so gradual over time that they just accepted it as not a problem, --and second, an older person's ears are not a 'tuned' as they once were to be able to detect something like the excessive clearance. And, most hobbyists are not that vigilant about removing the oil pan just to check the condition of the bearings just as a preventative maintenance item. At least with babbitt bearings, there is a much more forgiving and audible warning given.

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?

Bud, the answer to your question lies in which Flywheel housing you have. The stock Model-A flywheel housing with the small inspection cover will not let a rear main cap drop down low enough too clear the counterweights to be removed. The Model-B oil pan and flywheel housing were constructed to alleviate this issue.


..

 

[30 Closed Cab PU]

Assuming the motor has had the oil changed frequently, how often (miles) should the oil pan be dropped and -


Babbits be shimmed/wear inspected?


Inserts be wear inspected?

 

[BRENT in 10-uh-C]

Assuming the motor has had the oil changed frequently, how often (miles) should the oil pan be dropped and -


Babbits be shimmed/wear inspected?

Inserts be wear inspected?

The same question can be asked 'How long does it take to catch a fish?'


There really is not a known answer per se' simply because both have many variables. In the case of babbitt, what type/grade of babbitt was used by the rebuilder? -Was it peined in? -What was the finish like or was it burnished in? -How concentric was the crankshaft journal pin ground to?


In the case of inserts, what was the quality of the crankshaft finish and how accurately was the block line-bored?


In the case of babbitt, peining and burnishing allow the babbitt to become more dense, and the burnishing allows the babbitt to conform to the journal pin shape. This creates longevity. If a poor surface finish (looks like a handsaw's teeth under magnification) is what the babbitt looks like, then the babbitt will wear quick(er) as the crankshaft is only supported on the peaks --thus wearing quicker requiring more frequent adjustments.


In the case of insert conversions, more often than not you will find the machinists equipment is tired & worn which can cause a poor alignment issue. In modern engine applications, main journal hones that are longer than the engine block are used to ensure the journals are very straight. Unfortunately Sunnen does not make a small enough line-boring hone that will span the entire length of the A block to do all three journals at once. So if any bar deflection or set-up miscalculations during the line-boring process is/are encountered, it will prematurely wear the insert bearing.

Again, how often are most hobbyists doing routine inspections on their engines? Naturally the rebuilder wants to paint a rosy picture to their customer and they tell them it can go for a long time. Define "long time" accurately.

 

[30 Closed Cab PU]

The same question can be asked 'How long does it take to catch a fish?'


There really is not a known answer per se' simply because both have many variables. In the case of babbitt, what type/grade of babbitt was used by the rebuilder? -Was it peined in? -What was the finish like or was it burnished in? -How concentric was the crankshaft journal pin ground to?


In the case of inserts, what was the quality of the crankshaft finish and how accurately was the block line-bored?


In the case of babbitt, peining and burnishing allow the babbitt to become more dense, and the burnishing allows the babbitt to conform to the journal pin shape. This creates longevity. If a poor surface finish (looks like a handsaw's teeth under magnification) is what the babbitt looks like, then the babbitt will wear quick(er) as the crankshaft is only supported on the peaks --thus wearing quicker requiring more frequent adjustments.


In the case of insert conversions, more often than not you will find the machinists equipment is tired & worn which can cause a poor alignment issue. In modern engine applications, main journal hones that are longer than the engine block are used to ensure the journals are very straight. Unfortunately Sunnen does not make a small enough line-boring hone that will span the entire length of the A block to do all three journals at once. So if any bar deflection or set-up miscalculations during the line-boring process is/are encountered, it will prematurely wear the insert bearing.

Again, how often are most hobbyists doing routine inspections on their engines? Naturally the rebuilder wants to paint a rosy picture to their customer and they tell them it can go for a long time. Define "long time" accurately.

Thanks Brent,


Lots of great info as usual.


I figured the answer would be complex since I know very little on this subject and am trying to get up to speed. Am following this string since my A is in a restoration/repair shop for the winter. Motor rebuild may have to be done, and I want to make informed decisions.


Separately what I am hoping to get now is more along the lines of a very conservative estimate based on what others recommend of how often to Preventative Maintenance; check Babbitt's/shimming, and inserts. Am not looking for lifespan info.


I prefer this type of guideline since I do not have the experience, possibly hearing, to detect an issue before catastrophic failure.


If there are no general guidelines, OK, had to ask.

 

[BRENT in 10-uh-C]

Well, going at it like this, why don't you open it up after 5 yrs or 5k miles (-whichever comes first) to have a look/see. Inspect everything using a camera to document the condition of the bearing, and use Plastigauge o get a general idea of the condition. If all goes well, rinse & repeat in another 5 yrs. or 5k miles. Compare then to what it was prior and see where you are.


From my own perspective, you can be more lax on maintenance if you have babbitt bearings and it won't come back to haunt you as badly. Neither are very forgiving if the craftsmanship is faulty.

 

[30 Closed Cab PU]

Thanks, did not know enough 1st time and did not ask the right questions. Your response is what I was hoping for.


Am hoping the restorer will allow me to inspect once the pan is dropped, and educate me on the lower end of the motor - Babbitt shimming/inspection, etc. I also agree, am leaning towards Babbitt - do not want to add oil filter, pressurized oiling, and is more forgiving, etc. Also have noted your advice about craftsmanship, will ask appropriate questions when time to rebuild the motor.


Most likely a rebuilt motor will vastly outlast me, am 65 and I am not a high mileage driver.