I have thought these would be an improvement...
https://www.nurex.com/automatic-spark-timing-system-mechanical-advance-12176
https://www.nurex.com/automatic-spark-timing-system-mechanical-advance-12176
Engine Should Haves
- Thread starter Bob Bidonde
- Start date
Kurt in NJ
Well-known member
You have to look at them and check clearance,if they fail and get spun in the rod or block the crankshaft will be damaged along with the bore( block or rod) you can’t just replace insert.
With babbitt if you shut it down at first knocking most likely it’s just the babbitt.
With babbitt if you shut it down at first knocking most likely it’s just the babbitt.
Terry Burtz Calif
Senior Member
Kurt, Thanks for your reply.
Inserts can spin if rebuilders use old line-boring equipment that was designed for machining Babbitt bearings and has tolerances of +/- 0.001 inch.
Please be aware of builders that use old line boring equipment to machine bores for inserts. The old equipment is not rigid enough to hold tolerances of +/- 0.0001 inch required for inserts.
Kurt in NJ
Well-known member
It’s good that they can hold those kind of tolerance on your new engine,I have been curious about what tolerance they are machining to.
Has anyone ever opened up their post 1936 (year flatheads got inserts) and checked and adjusted bearing clearances?
I've assembled an 8BA flathead and there was no adjustment mechanism. Why would you adjust insert bearings on a Model A?
Do people leave shims in on an insert bearing modification?
Does the crank wear faster on a Model A?
BRENT in 10-uh-C
Well-known member
Many people have the misconception that if they have a Model-A block professionally converted to insert shells, then they can replace them if they become faulty or have worn out. In my post above, the definition of the term "maintenance" should include routine inspection of, checking clearance of, or replacement of.
I'm going to answer your questions as you have them listed....
▸I have a '32 Coupe that has an late '36 LB engine in it. Yes we/I have done "bearing maintenance" on it at around 40k miles after a rebuild which included removing the oil pan and checking clearances on each main & rod bearing. This is generally considered prudent when someone has a valuable or something that would be considered a difficult piece to replace.
▸Great question, ...but I am unsure why you are asking this as it appears YOU are the one implying someone is actually adjusting the insert bearing clearance(s). I don't believe anyone else used the term 'adjusting' in their responses above. Maybe I am wrong??
▸I don't use, -nor do I recommend using shims under caps on a Model-A engine that is being converted to inserts. Maybe others do??
▸Yes, Model-A crankshafts tend to be softer once the hardening has been ground through. I grind Model-A crankshafts in-house, and I can generally tell by the sparks when I have ground below the hard surfacing. Generally this factory hardening only penetrated 0.015" - 0.020" on each pin, -so generally speaking, if you have a stock A crankshaft that is ground .020, .030 or .040 undersized, yes it likely does wear faster.
Joe K
Well-known member
IIRC, Ford subjected each journal (proper name for the moving part) to a "roller high stress" which subjected the surface to "surface tension." As you say this thin "work hardened" layer is probably totally removed by 0.020 grinding.
Ford also pioneered "superfinishing" of the completed crankshaft.
Both of these are probably NOT done in modern "crank-grinding" with modern engines by in large relying upon "pressure lubrication" - and no metal to metal wear exists (theory) with the crank buoyed on "oil pressure."
That Model AA rolling chassis with 26K original miles comes to mind (I saw the odometer when the body was still on it) and likely had never had any engine shims removed. It was loose, no doubt, but seller and I "took it for a spin" before the transaction was complete.
I sold that chassis to a buyer who transported it to Texas. My regret since then is not overwhelming, but present.
Joe K
Well then I suppose that we're arguing semantics. When I hear maintenance, to me that implies actually maintaining something, not checking. If I check something and it's good, I don't do maintenance.
Checking and maintenance are two different things to most people.
Has anyone opened any of their cars in the past 70 years and checked bearing clearances? Is that in any of the Ford shop manuals?
BRENT in 10-uh-C
Well-known member
Geez, it would appear you are wanting to be argumentative. Again, no one except for you mentioned anything about 'adjusting' bearing clearances on an inserted engine.
As for "Checking" and "Maintenance" being two different things, please refer to Webster Dictionary and search for the official definition of Maintenance. It refers you to the Word Maintain. The root word of Maintenance has the definition of "...keep (a building, machine, or road) in good condition or in working order by checking or repairing it regularly:". There is that word 'Check'
As to your question about anyone opening up their cars (engine) in the past 70 years, it is my experiences that many hobbyists routinely open their engines and check bearing clearances. I believe if you will reference the Ford Model-A Service Bulletins, the Ford Labor Schedule Books, and even the Model-A Instruction Book, you will find written references to adjusting bearings when they become loose.
Your last question above is indeed intriguing. Surely we would all agree that someone will not find reference in any Ford Model-A Shop Manual suggesting Insert Bearings are to be checked in a Model-A engine, ...and likely because Ford did not approve of Inserts Bearing conversions on a Model-A engine. Alternatively, as an engine rebuilder I do make that suggestion to my customers. I would also make suggestions to my customer that they change their oil frequently -and that they even check their engine's oil & coolant levels before every operation. If they choose not to do these maintenance items, then that is their prerogative. I trust this makes sense.
Has anyone opened up a 1955+ year car, with insert bearings and checked the clearances as a regular "maintenance" item?
Is there a manual of a post 1955 year car that says at xxx,xxx miles you drop the pan and plastigauge your bearings?
I'm not talking about a babbitted Model A engine which the manuals are written to check bearing clearances.
I'm being argumentative because people are saying things that don't make sense and are being taken as gospel.
If there are reasons(Model A cranks wear faster with inserts, most insert jobs are not done correctly, etc) then I can see a point. But I don't think most people are opening up their Honda Civics and checking clearances, or their 8BA flatheads either.
And to be even more argumentative, at the Miriam-Webster website, the definitions of maintenance and also maintain do not have the word check anywhere in them.
1
: to keep in an existing state (as of repair, efficiency, or validity) : preserve from failure or decline
maintain machinery
Is there a manual of a post 1955 year car that says at xxx,xxx miles you drop the pan and plastigauge your bearings?
I'm not talking about a babbitted Model A engine which the manuals are written to check bearing clearances.
I'm being argumentative because people are saying things that don't make sense and are being taken as gospel.
If there are reasons(Model A cranks wear faster with inserts, most insert jobs are not done correctly, etc) then I can see a point. But I don't think most people are opening up their Honda Civics and checking clearances, or their 8BA flatheads either.
And to be even more argumentative, at the Miriam-Webster website, the definitions of maintenance and also maintain do not have the word check anywhere in them.
1
: to keep in an existing state (as of repair, efficiency, or validity) : preserve from failure or decline
maintain machinery
BRENT in 10-uh-C
Well-known member
My response to your comments is above in Red, -and my apologies to Bob for this going off-topic.
Bob Bidonde
Well-known member
Long ago I decided that an authentically restored Model "A" is not safe to drive in modern traffic. Moreover, it is way too expensive to authentically restore a Model "A", if not impossible to find the original parts necessary. My philosophy is to drive my Model "A" Fords, & do it as safely & reliably equipped as possible. Model "A" & "B" engines have lots of room for internal improvements that do not degrade the original outward appearance of the engines. The gigantic aftermarket of parts & gadgets for Model "A" Fords during the 1930s is proof that many many original & second owners thought about their car's engine like I do.
alexiskai
Well-known member
This hobby, these cars are fundamentally vehicles for self-expression (literally). It's been many decades since anyone bought a Model A because they needed a cheap car to get to work. Each car is a creative work. If we try to impose standards on the practice of the hobby, those standards will only succeed to the extent that owners see them as worth incorporating into the creative product they're trying to achieve. That's why none of these laundry lists ever work.
To me it's sort of like telling an Impressionist painter that a real Impressionist painting should be a landscape. Lots of great Impressionist landscapes out there! Lots of great ones that aren't landscapes too. Conflating your personal aesthetic preferences with someone else's just alienates people.
To me it's sort of like telling an Impressionist painter that a real Impressionist painting should be a landscape. Lots of great Impressionist landscapes out there! Lots of great ones that aren't landscapes too. Conflating your personal aesthetic preferences with someone else's just alienates people.
bobv
Senior Member
Brent, while I admire your dedication to the restoration of the mode A, I will respectfully say that I believe you may have a slightly different perspective concerning owning a model A than probably most on this forum. I think the majority here just wants to enjoy their cars and present them as they are, nearly 100 year old vehicles that they can drive and share with others without having spent $xx,xxx to restore. I park mine in the Walmart parking lot and don't worry much about it. Just my opinion
Just my opinion
BRENT in 10-uh-C
Well-known member
Brent, while I admire your dedication to the restoration of the mode A, I will respectfully say that I believe you may have a slightly different perspective concerning owning a model A than probably most on this forum. I think the majority here just wants to enjoy their cars and present them as they are, nearly 100 year old vehicles that they can drive and share with others without having spent $xx,xxx to restore. I park mine in the Walmart parking lot and don't worry much about it.
I likely do have a different perspective, -but is it possible you don't really know my perspective?
For clarity, my business is 110% restoring & repair vintage automobiles exactly how my customer wants them. I show no preference to customers who are seeking Concours-quality vs. Driver-level vehicles. Matter of fact, probably 95% of what we work on is considered Driver-quality since the customer typically wants every component on their vehicle to perform properly and reliably.
Now where I am different than some here is I am not a proponent of half-*** or shoddy craftsmanship done just to save a dollar, ...especially when it compromises safety or reliability. I also am not one to just bite my tongue when someone offers incorrect or misleading advice when my own firsthand experience has repeatedly proven otherwise. Bob didn't title this as Engine Must Haves, ...but he said Should Haves. As I said above, inserts are not for everyone -and I also say the same about hydraulic brake conversions, 12v electrical conversions, alternators, etc. Often times misinformation is spread using the 'excuse' that they want to drive or tour with their Model-A, and to do that it must have all these modifications.
alexiskai
Well-known member
I think a large amount of "you need this for touring" comes from folks being afraid that, if a certain component did malfunction on a tour, they wouldn't be able to fix it – maybe because it's impractical to repair, maybe because they don't know how to troubleshoot it.... maybe because it doesn't work correctly now and they're just living with it. Better to replace it with something that doesn't necessarily perform differently, but at least it won't embarrass them in front of the guys.
Not because I worry about being embarrassed (gave up on that years ago), but because of practicality. I am building my '30 Town Sedan into a touring car with 12V electrical with alternator. We've had club members have 6V components fail on the road with no commercial recourse (as I found out last summer when I blew both of my 6V headlamp bubs). 6V electrical components, including batteries, are simply not available at the NAPA in whatever small town you might be passing through.