Bad day for babbit
 

My 30 coupe started getting a little loud, I opted to leave it parked for about a month before I got the itch to dive and see what was wrong. I was hoping it was a shim that needed to be taken up. Well I drained the oil and dropped the pan and was met with some not so friendly chunks of metal in the oil pan.

The 2nd Cylinder connecting rod was missing some babbit along the edges of the rod cap. So I took the cap off and was met with what you see in the attached photo.
I can't say for sure that it's a workmanship issue or if it's just a stroke of bad luck- as I'm not sure who did the work in the past . But the rest of the engine looks immaculate. cylinder bores look good cam is in excellent shape and until I took it apart it's always started reliably. I truly suspect there aren't that miles on this engine since it's last overhaul-but I don't really know any of it's past.

So my question is what would you do in the situation?

Re: Bad day for babbit
 

I think a lot depends on what your goal is. If it is to simply remedy the situation with the least reasonable hassle and cost, I'd verify that the rest of the babbetted bearings are in good shape (rods and mains), measure up the rod journal to be sure it's not oval or tapered, and if it measures up OK then replace the single rod with a rebabbetted rod. Snyders sells rebabbetted rods. Your rod balance may not be perfect but that's sort of a chance you take by minimizing the amount of work you do.

If your goal is to use this opportunity to do a more complete engine rehab, I'd consider a Burtz Block kit using your existing engine guts. You can use your exisiting cam, head, flywheel, oil pump. maybe even valves and lifters. By the time you either rebabbett completely or insert/balance your engine, you've almost bought a Burtz Block kit.

Re: Bad day for babbit
 

My Engine builder highly respected in Massachusetts, suggested that to ensure the engines longevity that I inspect the bearings at 10000 miles just to be on the safe side.On my inspection all was o.k.
I believe that most people don't do preventative maintenance on their engine bearings and just wait until a noise appears which in many cases it is too late the damage has already been done. I know its a pain in the B to drop the pan or remove the Engine, but IMO it is reassuring and cheap insurance to know that everything is ship shape in that department.

Re: Bad day for babbit
 

Find a better qualified, more competent Rebuilder. Truth being spoken, it seems there are many Restorers who still find a rebuilder that works out of their backyard rebuilding engines (-maybe because of price??). These backyard guys 'farm out' the boring, honing, decking operations to a qualified machine shop that has the equipment to do these ops but these same backyard babbitt experts tend to use improper materials and methods.




This is sound advice.


Yes, the noise likely could have been heard much earlier but so often I find the driver was hard of hearing so it had to become audible enough for the driver to think he might be hearing something, ...at which time, it was generally too late.

Re: Bad day for babbit
 

I will second Jay Jay on this one.

Re: Bad day for babbit
 

If I were in your shoes, I would inspect the crank bearings. If they were good, I would pull all the rods, measure the crank, and swap in a set of properly sized, inserted rods, then drive it.

If you were in my shoes, you'd have no shoes on, so take the advice above as just an opinion.

Re: Bad day for babbit
 

Oh, I like that!

"If you were in my shoes, you'd have no shoes on, so take the advice above as just an opinion."

Re: Bad day for babbit
 

What Paul said in Post #6 is a good suggestion.

Re: Bad day for babbit
 

The only issue with that logic is not all engine rebuilders (-myself included) grind crankshafts back to a nominal 0.010", 0.020", 0.030" etc. size. If I can regrind a crankshaft where all the rod journals cleaned-up at 1.493", I will machine the rods to come in at 1.4945". The less you take off of a Model-A crankshaft, the better you are since the heat-treating is not very deep. It also may allow that crankshaft to have a 2nd grinding later on and still be 0.010 undersize.

Re: Bad day for babbit
 

Since one rod is bad it could be that the Babbitt on that rod was bad or that there is a misalignment issue. A bent rod or a cylinder not bored square to the crank can cause all sorts of problems.

To answer Bret's concern, measure the journal. You should do that anyway to make sure is not out of round or tapered or worn too much. Use a good quality micrometer.

Re: Bad day for babbit
 

I understanding routine maintenance. But How would that have prevented failure of this bearing? What should I have done differently?

I am fortunate that I have a few micrometers that I actually just got from an elderly gents estate. 1 and 2 inch. So I should be good on that.

I'm still weighing my options here. Do I just repair whats damaged or have the whole block gone over and rebuilt I understand one is a band aid. But the cost of rebuilding is...prohibitive. As is the paint when I bought the car looked very good and in the few years I've owned it now has completely failed,despite being kept indoors. So now I have 2 big bills coming up and I have bearly put 1000 miles on it since I've owned it.

Disheartening for sure.

Re: Bad day for babbit
 

The minimum is one new rod with insert bearings. The next level up is 4 new rods with insert bearings. You probably do not need a complete overhaul at this point but check the clearance on the mains with Platigauge or other means.

A rod bearing can fail because it was not done right or it can fail because the ignition was too far advanced, especially with a high compression head. But usually in that case all 4 rod bearings would have failed.

When you get the engine back together make sure you find the knee in the ignition curve and then run one notch retarded from there.

The paint has failed because it was not done properly. The paint manufacturers have specific information on the process and this must be followed exactly. You can re spray the car yourself but it is a lot of work. You must use personal protection devices to keep from breathing the fumes and to keep the paint out of your eyes. Modern paint is very toxic. See selfie of yours truly.

A good spray gun is a must. The modern guns are high volume, low pressure. If you put on enough paint you can wet sand and polish the paint after it dries to make it look like a professional job.

Re: Bad day for babbit
 

I've got a fresh set of re-babbit rods. I'm going to build a B with insert bearings so I no longer need them.
If you are interested I can measure to see if they are standard or undersize. $250 for the set + shipping.

Re: Bad day for babbit
 

Chris,
Sorry to hear about your engine. If it was mine, I would pull it and disassemble it to check the other bearings, both rods and mains, for their condition and clearances. You can also assess the rest of the motor while it is apart.
If the rest of the motor is good and the mains are good, I would look at replacing the rods with a rebabbitted set. You could likely go to Schwalm's and have a set done and fit to your crank and have the pistons put on the new rods.
This is what I would do. However, if you are interested, I'll give you one of my spare motors.....