line boring delima

All of this is why I went with a new Burtz block. Still lots of good old original engine blocks out there to rebuild, but the ones I had at the time where needing rebabbiting and also had some threaded holes that were in bad shape, not to mention some hair line cracks to be delt with. Love my model A's and love to drive them.
 
It won't be cheap, but I like the builder mentioned in post #5 by nkaminar (https://www.harringtonsmachineshop.com/) if they have a small boring bar and can machine the main bearing bores in the correct location. If they machine modern cylinder blocks, they will have good line boring equipment and can machine your cylinder block. I suggest adding dowel pins between the main caps and cylinder block because the bolt holes are sloppy and will allow the caps to shift.

Line boring equipment designed to machine Babbitt is not as stiff or accurate as modern line boring equipment used to bore cast iron. Older line boring equipment may be worn.

What inserts are you using? If it took several months of searching for inserts, what will happen when the engine needs to be rebuilt? Consider using a common insert that will be available in the future. To find a suitable insert, download the Clevite Mahle catalog EB-20-18. To get the insert OD and ID correct, you may need to use a metric insert.
 
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I've been working on a few engines now, I'm only babbitting them, if i find a block that has inserts in it i will either braze it or crush it. inserts don't work. period. if you aren't trying to break speed records babbitt is plenty strong. Henry had literally hundreds of engineers working on this car, and he made darn sure it was as good as it could get. Babbitt is still used in steam turbines that take far higher loads than any model a crank or rod. inserts are an expensive solution to a problem that doesn't exist
 
Sunny the Model A said:
I've been working on a few engines now, I'm only babbitting them, if i find a block that has inserts in it i will either braze it or crush it. inserts don't work. period. if you aren't trying to break speed records babbitt is plenty strong. Henry had literally hundreds of engineers working on this car, and he made darn sure it was as good as it could get. Babbitt is still used in steam turbines that take far higher loads than any model a crank or rod. inserts are an expensive solution to a problem that doesn't exist
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You must only have junk come across your shop. I’ve seen more perfectly fine babbitt and inserted engines than I have junk babbitt or insert engines.

Inserts work perfectly fine when properly machined for them, just like babbitt.

Steam turbine loads are completely different than combustion engine loads.
 
that graph was likely made by someone who hates babbitt. i've taken A motors apart on original babbitt stilll going strong, just took out a shim and kept on truckin'. but insert? crushed 3 blocks that had spun inserts and cracked the rear main web. nothing but junk. I'm converting my 91 S10's 4.3 to babbitt bearings since the engine is on it's last legs and starting to have noise in the bottom end. going to do a points conversion, stromberg 97 carb, babbitt bearing conversion, and lower the compression to 5.5 to 1 so i can roun it on multifuel. stupid thing never starts up without a fight. and has nothing but trouble. my a fires off on the second compression stroke every time. the reason i referred to a steam turbine is the bearings in a turbine of that size take far higher loads then a an a engine ever will. I've even rebabbitted a Cat D3400 diesel that was babbitted, it's 16-1 compression. if that engine can survive a d2 bulldozer with babbitt, an A engine can last a lifetime with babbitt.
 
Or the last 75 years of inserts as an industry standard is just a fad

Properly designed Babbitt bearings work
Properly designed inserts bearings work

Improper application is a recipe for disaster

J
 
Some crazy **** being said here. After babbitting and align boring 2-300 model A,B, and V8 blocks successfully over a long period of time I can say there is nothing wrong with Babbitt for a stock or lightly modified A or B. But after dealing with trying to find good blocks to use getting a Burtz was for me and still is a no brainer. Sure it is not for everyone and is costly but when you look at cost versus longevity and piece of mind the Burtz is the only way to go. From a professional point of view putting your reputation on the line building 100 year blocks comes with a certain amount of risk I used a Kwik way bar with four towers, the line up fixtures and power feed at .005 per revolution. The cranks always turn by hand and the motor would start on the starter. None of this pushing the car to get the motor to turn crap. I mentioned earlier in the thread about using a Tobin arp TA-14 or 15. They have a small bar and will do the job accurately. The one I bought came out of a large well known diesel engine shop in Boston it was fully capable of line boring just about anything you could physically fit on the table. The idea that inserts don't work is ridiculous. What doesn't work is a HACK job. Line boring an A or B requires boring cast iron and steel. Welding up the crank and moving the thrust to the center has led to many failures, broken cranks and cracked blocks. May not be such a good idea. Modern shops have boring bars with a bar that may be too large for the A or B block. The bearings that Terry chose are one of the most common inserts used on the planet fitting small block Chevrolets. CB 745 and 663 are known to just about every engine builder or where at one time.
 
I have been rebuilding engines since the early 80’s. I’ve poured hundreds of engines using modern high speed babbit. I have all KR Wilson pouring dies and boring fixtures. I have no problem with Babbitt bearings, but agree that if the machine work for inserts is done correctly, they should be fine as well. As a matter of fact, inserts put me out of business, so now my operation is stored, idle and will remain that way…perhaps until there is another trend. I even sold my crank grinder to the scrap man because it had too much taper and too expensive to scrape the ways.
 
Sunny the Model A said:
that graph was likely made by someone who hates babbitt. i've taken A motors apart on original babbitt stilll going strong, just took out a shim and kept on truckin'. but insert? crushed 3 blocks that had spun inserts and cracked the rear main web. nothing but junk. I'm converting my 91 S10's 4.3 to babbitt bearings since the engine is on it's last legs and starting to have noise in the bottom end. going to do a points conversion, stromberg 97 carb, babbitt bearing conversion, and lower the compression to 5.5 to 1 so i can roun it on multifuel. stupid thing never starts up without a fight. and has nothing but trouble. my a fires off on the second compression stroke every time. the reason i referred to a steam turbine is the bearings in a turbine of that size take far higher loads then a an a engine ever will. I've even rebabbitted a Cat D3400 diesel that was babbitted, it's 16-1 compression. if that engine can survive a d2 bulldozer with babbitt, an A engine can last a lifetime with babbitt.[/QUOTE)




Sunny the Model A,

Thanks for your post and comments.

The Caterpillar D3400 engine was built from 1935 to 1945. Every D3400 engine that left the factory used insert bearings, not poured Babbitt.

My 1947 Federal Mogul catalog specifies inserts for the connecting rods and main bearings for the D3400 engines. The rods use insert #1005B, and a set of main bearings is part number 619 M.

Cat engines started using inserts in WW1 because they could be easily replaced during crop harvesting or on the battlefield.

Did you reline the Cat inserts, or throw them away and pour extra thick Babbitt?

Do you use salvaged Babbitt from cylinder blocks and connecting rods that are scrap, or do you purchase new Babbitt?

Regarding your 1991 S-10 pickup that you plan on converting to poured Babbitt bearings, I wish you good luck and looking forward to your reply on FordBarn.

Please reply.
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When insert bearings are set up with the proper crush they cannot spin unless you have a complete failure of the lubrication system!!!
 
It sounds like you are getting yourself into a very questionable area of having successful results. Experienced precision machining is very important for successful results.
Maybe it would best to stop and change direction. Sell what have and buy a Burtz short block. That's what I would do.
 
In reference to that graph. Both my federal mogul and mcquay Norris bearing manuals have similar charts and a whole lot more information. There is nothing wrong using Babbitt where Babbitt was used before, not just automotive but an incredible list of applications. But the facts are the facts. Any Babbitt more than .002 thick has so little strength it is virtually off the charts. Yes inserts may be less forgiving than Babbitt but as far as strength and longevity it was learned at least 80 years ago inserts are just better.
 
Probably the most important aspect of insert bearings are the changes to lubrication system
Just as the change to full filtering oil increased engine life the move from gravity/splash to pressure fed changed bearing design

Not that I am the expert on bearing failure analysis what I have witnessed leads me to the conclusion that mis-applying either will result in unsatisfactory outcome

John
 
In 2008 I sent my block to AER and Rick line bored it for inserts. I assembled the engine, designing my own full pressure oil system with remote oil filter. The oil goes from the pan to the pump and then to the oil filter before going to the engine. This setup has been working for 16 years and 35,000 miles without a problem. I have gone on many long trips (more the 1200 miles round trip) without a problem. I expect this engine (system design is posted on VFF) to outlast me (at 79). Inserts work great, but you have to have 100% filtered oil for longevity.
 
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