The Stovebolt Site Forums The Shop Area Engine Shop Re-Babbiting!

Has anybody heard of it? I was surprised when I heard people still do it. I guess it's rare but a couple outfits still do it PA. That's what is getting done to our rods right now.

I'm about to start the rebuild procedure on a Model A engine that has babbited rod and main bearings. It's going to be a challenge to do the re-pour on those mains, or make the pouring jigs to do it myself if necessary. There are a few places that still rework rods, but the "centri-cast" process Chevy used to spin-cast the Babbit bearing material is no longer done anywhere, to the best of my knowledge. It resulted in a thin, uniform layer of bearing material being deposited on the rod which required a lot less finish machining. The rebabbited rods which are available today are mold-poured, a good, but not original-equipment process.
Jerry

I am planning to babit the rods in my 235 but right now its a very back burner project.

Spin casting is still done:

Fusion Babbitting Co Milwaukee, Wisconsin 800-613-5118

The hard part (kinda) would be to calculate the exact amount of babit to add to get the desired thickness. For most con-rod sized objects spinning at about 400RPM generates about the proper force to coat the surface.

I have some sketches of how you could make a jig for 2 rods. Bolt them down, heat, spin, add babit, cool, scrape, done.

Wish I had known about any PA machine shops that do babbiting.
Some time ago I sent rods to EGGE in CA for that process.

I would think that there are some Amish farms that still do it. But you'd have to know someone that knows someone etc etc.

I know there is at least one Amish family that is doing one off cast iron pours.

I have used a mold to pour Babbitt in rods for a hit and miss engine.It was not to hard to do,and the machine shop did the mill work.It all turned out good.I have never done main bearings,but don't think it would be to hard to do.

You can get insert bearing modified rods and caps for this engine. That's what I would do. I spent over a grand on rebabbiting a 216 because its a lost art and they can charge anything they want. I wouldn't do it again.

I've got a boring jig about half finished to mount a stovebolt connecting rod onto the carriage of my lathe and chuck a micrometer-adjustable boring tool in the headstock. I can rough out a reconditioned rod that's deliberately poured smaller than the crankshaft, and finish-scrape it to a perfect fit with the crankshaft, then shim it for the proper oil clearance. Cutting the lube grooves can be a bit tricky, but with a lathe big enough to spin the rod over the ways and a 4-jaw chuck it would be possible to clamp the big end into the chuck at an angle and machine one groove, then flip it over and make the intersecting one. The alternative would be to freehand oil grooves with a carbide V tool in a die grinder.
Jerry

A grand? OUCH!

I don't believe it to really be a lost art.. just not done. Its a mechanical process. There really isn't much to it and references are available. You just gotta want to do it. The great thing about babit is if you mess it up you can take it out and to it all over again.

I would agree that inserts are much easier. But whats the point of keeping a 216 if you take away one of the unique things that makes it a 216? Just put in a 235 full pressure motor and few people will ever know.

Hmmmmmmmm a grand to have it done...........Pick up the yellow pages and see how many places can pour babit bearings. I do believe that its a lost art.

EGGE charged me $300.00.

I agree. On my original 216, I used aluminum piston and drilled the crank snout. But, I was able to remove shims and get .002" on all the rods with original Babbit. The lighter pistons should help prolong the life of the babbit, I hope.

I certainly would have gone with rod bearing inserts if the original brabbiting was not serviceable.

Yeah…we went with aluminum pistons as well. However we did opt for re-babbiting the rods. Had the crank turned down also. And bored the cylinders to .040. New mains, new valve seats and valve guides. Should run like new….I hope

I am curious if a certain type of break-in oil is required for these engines after getting this type of work done. Anyone have any suggestions?

Thanks

It would be easy to put the rod on a bridgeport with a rotary table and cut the the oil grove with a side cutter. Or clamp it to the table and cut it with an indexable boring bar.

I think the inserts give a more modern and better bearing setup than the originals. There are plenty of shops that can macine the rods to fit the inserts.

The connecting rod boring machine I used at the machine shop where I worked part time for about 5 years could hold a .0002" oil clearance on a Cummins wrist pin bushing and do it without needing any finish honing, using a sharp carbide-tipped cutting bit. It could also be used to machine the big ends of con rods, but it needed to have coolant running to work steel. We usually ground or filed rod caps and finish-honed the big ends with a Sunnen PowerStroke hone to avoid setting up the boring machine for steel several times a day.

When I had a bunch of Stovebolt rods to convert to insert bearings, I did use the rod boring machine and coolant, but tying up a $60,000.00 machine for converting just a few rods was not cost-effective. I usually used a Bridgeport with a precision boring head to rough out the rods, and then cut the final .002" or so on the Sunnen hone. That particular shop didn't rebabbit rods or main bearing bores in blocks- - - -just not enough demand for the service to justify the cost of setting up for it, or training people to do it.
Jerry

I have a couple old bars of babbit mat'l here that I picked up in my travels.
Is it worth anything? Or just cool to have for the cast writing on top of it.

Is all the babbit the same mixture or is the lead / tin content different?

The supplier I use to provide the tin and antimony used for bullet casting also has Babbit metal, available in about 5 or 6 different alloys. The mix they reccomend for connecting rod and main bearings is much harder than the other alloys used for rotating shaft pillow blocks, etc.

http://www.rotometals.com/Babbit-Bearing-Alloys-s/2.htm

Jerry

With a Model A engine, the main bearings would have to be poured and then line bored in the block wouldn't they?

John

Yes, that's right. One of the oldtime Ford service manuals I've got describes "burning in" the main bearings, clamping a hard steel straight bar up in the main bearing bores and turning it with a big electric motor WITH NO LUBRICANT! "When all the bearings are smoking well, stop the machine, insert the crankshaft and scrape the bearings to a perfect fit". How's that for a challenging way to fit bearings? Fortunately, I've got a friend with a portable line-bore rig that roughs-in the bearing diameter close enough to drop the crank in and do the final bearing scraping by hand using Prussian Blue. Once it's a good fit with no high spots, the bearing caps are shimmed for the correct oil clearance, usually .0015"-.002".
Jerry

Yeah, where I am located, its GONE. The guy who was left in Wichita died from old age. I am sure there is someone in SOCal or maybe on the east coast that still does it, but for most of us, the cost is outrageous and when it comes to a thousand dollars vs insert bearings, my high horse can be whittled down a bit. Good news is, mine was rebabbited and done right, bad news, never again.

It looks like you've got a golden opportunity there to cash in on an obscenely profitable way to fill a need- - - -unless you think you're not capable of learning a fairly simple skill. Us oldtimers will all be gone before too long, and the young troops are either unable to learn the skills we picked up from our forbears- - -or they're just too lazy!
Jerry

Im on the same page Jerry. See it every day. Sad sad SAD! Part of the reason its not coming back is because of demand. There just isn't enough people who are purist enough to care since inserts are available. If I had more than a few 216's in my inventory, I would really consider learning. Especially from you. But I have 10 235's and 2 216's that are already done. My vote is LAZY. See it all the time. Pathetic

Well, the demand seems to be there- - - -I've got an invitation to go to New Zealand sometime soon to assemble a spare engine for a 1925 Dodge 1-ton truck that belongs to the 4th. generation of a family that once owned the largest winery there. The vehicle is driven in parades, etc., in very good unrestored condition, and they want to have a spare engine on hand in case it's ever necessary to make a swap. The same guy who owns that rig has a racing Toyota Supra he bought with the engine in a box, so I'll also get to play with a hotrod while I'm there!
Jerry

Very interesting topic. as noted it'll be a shame if these old techincal skills fade away in obscurity....

re. New Zealand. Jerry, a good friend of mine spent a yr in NZ upgradeing their telco central offices and he really liked it there.
Do you like lamb?
Back a few yrs ago I went to a tech school to get familure w/a product that was developed by a NZ company and the instructors and staff were all New Zealanders, great people. Only problem I had was to get them to slow down alittle so I could understand them
Have fun and take a good book, it's a long flight.
Dave

What I'd like to know more about is the "scrapping" to fit part of the process. But wouldn't mind see the babbit pouring part too.

John

Google/yahoo/Bing search on the following: youtube babbit bearing pouring

Scraping is the easy part- - - -just coat the bearing surface with an indicator dye like Prussian Blue, put the shaft into the bearing, clamp the cap on with just a little pressure, and rotate the shaft. When the shaft is removed, any bright area in the bluing is a tight spot. Using a tool like a 3-cornered file with the teeth ground off, gently scrape a thin layer of Babbit away where the bright spot is. Recoat, insert the shaft, "rinse and repeat" until you get a smooth smear with no high spots, indicating a 100% shaft-to-bearing fit. Then shim the cap to achieve whatever oil clearance you want. When dealing with multiple surfaces like a crankshaft in a set of main bearings, it's a good idea to work all the bearings at the same time. Otherwise, fitting one bearing can alter the fit of the next one in line. I've seen a few oldtimers fit bearings so tight that the car had to be push-started with sandbags in the trunk for traction, but that was just too tight to suit the guys around our shop back in the 1950's. Fun stuff!
Jerry

Edit: One sneaky trick is getting the Babbit metal to bond well to the steel or cast iron connecting rod, block, etc. It's similar to the way our body shop man got body fill lead to stick to sheet metal. Coat the area with acid core solder and use a coarse rag to wipe away any excess while it's still hot, leaving a thin, shiny tinned surface. The Babbit bonds to the solder, leaving a high-strength bond to keep the bearing material from spinning.
Jerry

Ya know...If I already didn't have a business to run...I'd consider learning that trade and look into the machines and tools needed...and go from there. Too many irons in the fire now, don't wanna add babbit to it just yet

With prices all over the place (so far we've heard $300 to over $1000) that it more likely the reason its not done. As with any process if you stick with one motor (say 216s) and get all the jigs and fine tune the workflow you could easily make money on the lower end of the scale.

Babit or titanium you only need to be good down to a ten-thou. Even that is probably overkill.

Now if the owner thinks that his newly babited motor is gonna last 50k that's possible... but not likely. The perception that it shoudl last as long as a modern bearing is going to be more of an issue that melting some metal and pouring it.

What do you think that soft metal middle layer is on an insert bearing? Oh yeah- - - - -it's Babbit! The pricey "race-only" bearings we paid twice as much for as "street" bearings- - - -they're made with a slightly thicker Babbit layer- - -without the .0003" thick pure tin layer on top for quick break-in, and an extra thousandth of oil clearance. Babbit is actually BETTER and longer-lasting under high-load and extra clearance conditions than the softer insert bearings that replaced the poured and scrape-fitted ones, plus it can have the clearance adjusted repeatedly by shimming!
Jerry

That is what I've heard that babbit isn't as bad as many think it is. It was actually pretty durable material.

Now all we need is a melting pot...... John

The only thing to significantly change for main/rod bearings is the ease at which they can be replaced. Yes, they still run on babit material, but other than checking the journal for wear you really just replace them.. no molds/fitting/scraping etc. You can get a complete bottom end done for the cost of the bearings is all are in spec.. that's maybe $100-150.

But the to pay shop rates to have all that babit work done... yeah.. you gotta WANT the original to be able to justify it.

Plus that older thick babit could embed a boulder and still run. Now a days 20-30 micron particles wears it all out.

If you changed the oil, ran filters (both full and bypass) and and keep the RPMs under 2000-2500 I don't see what's stopping a properly done babit motor from lasting 50-75k or more.

The whole problem is that it can cost you (as mentioned) a very pretty penny to do it.

I've always wanted to take a scraping class... and I have done some very small projects (some smaller gibbs, and vices) but there is a lot to it when you get into the minutia of it. Its still done on higher end machines... there are lots of youtube videos showing how to do it.

I recall as a kid my oldest uncle telling me about this process. He mentioned using a kerosene lantern with the wick up high to coat the shaft with soot. The soot would establish the oil clearance if I recall.
He also mentioned scrapping using the edge of an old piston ring.

He's long gone. I wish I had paid more attention then.

A jig would be super easy to make and that would ensure the oil clearance. I think the biggest expense most shops have is that the have to scrape the babbit. That's time consuming. A precision mold would cut the labor time considerably.

I cast bullets and use soot as a release agent for the mold.

I know this is an old topic, but just wanted to throw in my 2c.

When I was running Model A's with Babbitt bearings, I made the mistake one time of getting one too tight. I was on a date heading to a show, when about 10 miles into the trip, a rod bearing melted out. Fortunately a buddy was behind me heading to the same place and picked us up.

Jerry's thing about tinning the iron so the babbitt wouldn't spin out was taken care of on the Model A Ford with a few blind holes drilled into the block and cap to lock the poured material in place. I knocked the worn out Babbitt out of one engine and didn't find any evidence that the block had been tinned at all, just pegs of bearing material where it had flowed into those holes. I had one engine redone at a shop in Fresno, probably long gone by now, as that was back in the late '60s.

Done properly, a Babbitt job can last a long time, removing shims to keep the clearances proper (but don't get them too tight). As was mentioned, they will embed pretty large particles and not damage the crank journal enough to require grinding.

I haven't torn into my 216 on the '51, and don't necessarily plan on it. It runs pretty well as far as I can tell, but I haven't put a load on it. We shall see when it comes time to get it on the road again.