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Old 10-18-2020, 06:49 PM   #1
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Default Time lapse Model A engine build

Saw this on Youtube be nice if it would go this fast... enjoy



https://www.youtube.com/watch?v=GGn-5VoS-m8
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Old 10-18-2020, 07:26 PM   #2
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Default Re: Time lapse Model A engine build

Great fun to watch.
Liked their heating coil they used to loosen head & manifold studs.

It would have been really easy to paint the oil pan black.
Same for green on the intake manifold & flywheel housing.
My OCD is showing a little......
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Old 10-18-2020, 07:31 PM   #3
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Old 10-18-2020, 09:03 PM   #4
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Default Re: Time lapse Model A engine build

That heat coil is amazing. The local garage that I often help out has one. It works well especially on manifold bolts. Pricey, but once you have one you'll wonder how you lived without it. The next best thing to owning one yourself , is to know someone that does.
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Old 10-19-2020, 04:15 AM   #5
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Default Re: Time lapse Model A engine build

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Saw this on Youtube be nice if it would go this fast... enjoy



https://www.youtube.com/watch?v=GGn-5VoS-m8

I enjoyed the video. Thanks for posting.


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Old 10-19-2020, 08:13 AM   #6
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Fun to watch, went so fast but I did not notice any assembly lube on the crank and cam, perhaps I missed it.



Wonder why they tow strap started it, shouldn't it start via the starter? Am asking since I have never seen a fresh rebuild start.
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Old 10-19-2020, 08:25 AM   #7
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Wonder why they tow strap started it, shouldn't it start via the starter? Am asking since I have never seen a fresh rebuild start.
The engine was too tight for the starter to turn over. There is another video about the assembly and he mentions it.
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Old 10-19-2020, 08:49 AM   #8
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Fun to watch, went so fast but I did not notice any assembly lube on the crank and cam, perhaps I missed it.



Wonder why they tow strap started it, shouldn't it start via the starter? Am asking since I have never seen a fresh rebuild start.
If you search for "Hagerty" on previous forum posts you'll find a multi-page argument about the bearing clearance choices made by the engine rebuilder they hired to do the babbitt. Tight bearings is the reason for the tow start.
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Old 10-19-2020, 09:26 AM   #9
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If you search for "Hagerty" on previous forum posts you'll find a multi-page argument about the bearing clearance choices made by the engine rebuilder they hired to do the babbitt. Tight bearings is the reason for the tow start.
I have participated on Fordbarn for better than 20 years or so, and this has always been a topic of discussion. Originally when Ford authorized shops did the rebuild, they used a large burnishing machine to 'fluidize' the cast bearing material so it would conform to the journal pins. Fast forwarding to modern-era rebuilders, most must compete on a price-point which does not allow the extra time for them to burnish bearings. The alternatives at that point are to set them bearing clearance up looser so the starter can rotate the engine, -or set the clearances tighter requiring mechanical assisted starting until the engine has self-burnished the bearing. Part of the issue is if the bearing clearances are left loose enough to rotate freely, as the engine breaks-in the clearances becomes excessive creating noises the car owner complains about. Since most do not wish to adjust (tighten) the clearances themselves, it is easier for the engine rebuilder to set-up the engine tighter to alleviate the need for adjustment within 500-1000 miles.
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Old 10-19-2020, 09:50 AM   #10
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Old 10-19-2020, 10:27 AM   #11
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Default Re: Time lapse Model A engine build

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Originally when Ford authorized shops did the rebuild, they used a large burnishing machine to 'fluidize' the cast bearing material so it would conform to the journal pins. Fast forwarding to modern-era rebuilders, most must compete on a price-point which does not allow the extra time for them to burnish bearings. The alternatives at that point are to set them bearing clearance up looser so the starter can rotate the engine, or set the clearances tighter requiring mechanical assisted starting until the engine has self-burnished the bearing.
Is the crankshaft hard enough to serve as an adequate substitute for the OEM roller burnishing?
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Old 10-19-2020, 12:55 PM   #12
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Is the crankshaft hard enough to serve as an adequate substitute for the OEM roller burnishing?
Yes. The crankshaft was the original burnisher. Even on a rebuild where the crankshaft has been resized, it is an advantage to use the crankshaft to burnish.
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Old 10-19-2020, 05:32 PM   #13
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I have participated on Fordbarn for better than 20 years or so, and this has always been a topic of discussion. Originally when Ford authorized shops did the rebuild, they used a large burnishing machine to 'fluidize' the cast bearing material so it would conform to the journal pins. Fast forwarding to modern-era rebuilders, most must compete on a price-point which does not allow the extra time for them to burnish bearings. The alternatives at that point are to set them bearing clearance up looser so the starter can rotate the engine, -or set the clearances tighter requiring mechanical assisted starting until the engine has self-burnished the bearing. Part of the issue is if the bearing clearances are left loose enough to rotate freely, as the engine breaks-in the clearances becomes excessive creating noises the car owner complains about. Since most do not wish to adjust (tighten) the clearances themselves, it is easier for the engine rebuilder to set-up the engine tighter to alleviate the need for adjustment within 500-1000 miles.
Are you saying that the assembly of the engine in question was done correctly being assembled as tight as it was (in the other video of the assembly)?. I ask because, as i remember there was a LOT of dissension among the ranks regarding the tight tolerances used on the bearings which surprised me as i would have thought that they guys from Hagerty would know the proper procedure prior to assembling the engine.
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Old 10-19-2020, 09:58 PM   #14
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Default Re: Time lapse Model A engine build

How about the red coating (some builders use this) which looks like Glyptal from past decades, that's inside the block ? Can that come off and / or does it block passages in any way?
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Old 10-20-2020, 07:00 AM   #15
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Default Re: Time lapse Model A engine build

I have disassembled several engines that were being run regularly, and a few that have sat up for years, including a flathead Dodge I rescued from an overgrown fence row.
Never saw any meaningful amount of rust inside either crankcase or valve chamber.
For that reason I would not bother with the red paint inside a new engine....
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Old 10-20-2020, 08:23 AM   #16
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Are you saying that the assembly of the engine in question was done correctly being assembled as tight as it was (in the other video of the assembly)?. I ask because, as i remember there was a LOT of dissension among the ranks regarding the tight tolerances used on the bearings which surprised me as i would have thought that they guys from Hagerty would know the proper procedure prior to assembling the engine.
Often times in specialty topics such as this, jealousy and personal agendas tend to overshadow facts. Dissention is often the results.

While I have not reviewed the video in awhile, as I recall, they towed the 'tight' engine for 20 feet or so and the engine started. I don't recall any sliding the drive wheels because the engine was so tight, or jumping up & down on the hand crank because the engine would not turn. As I stated earlier, the Ford-approved procedure was to burnish the cast bearings. I doubt there are a handful of us engine rebuilders that do this operation today. For the ones that choose not to burnish as part of the rebuilding procedure, then setting clearances up a little tighter and allowing the cast bearing to fluidize during the initial starting is likely the next best way.



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How about the red coating (some builders use this) which looks like Glyptal from past decades, that's inside the block ? Can that come off and / or does it block passages in any way?
This topic has also been discussed at length here. "Can that come off and block passages..."? Yes it can, ...however it usually does that when the insulating varnish was applied poorly. Some rebuilders never have this become an issue on engines they rebuild.

This controversy (IMHO) stems from the facts that not all engine rebuilders have a good way to clean parts. And, ...not all engine rebuilders take the time to thoroughly clean all the parts. The cleaning process when done correctly takes time and requires a large financial investment to have the proper equipment. I personally have a 3 step process in 3 separate machines that takes it from greasy to clean. It really should not matter whether the cleaning process is done thermally or by chemicals as long as the oils are completely removed from the pores of the cast iron. Residual oils in pores, crevasses, or obscure corners are what causes the varnish not to adhere properly. Get them clean where the varnish can grip into those pores, and you will find it is very difficult to remove it during the next rebuild.

Just so we are clear, the main reason for using varnish (-such as Glyptol which is still available) is for insulation and oil control. Rust prevention is secondary or even thirdly. Windage inside of a Model-A engine is pretty rampant which affects the engine oil location and temperature. Having a smooth surface where the oil does not cling to that surface is ideal. This ultimately places the oil back in the pan where it can be cooled. Varnishing also seals the metal pores where any suspended debris cannot attach itself to. This debris can be anything from the cast iron being scraped off of the cylinder walls due to friction, to piston rings being abraded away, to metal wearing off of a camshaft lobe or tappet, -or just general carbon & coked oil. As far as insulating properties, consider what is being transferred into the valve chamber are through the roof and backside of the chamber -and why. While some argue the effectiveness of the insulation, I feel it really boils down to whether it is a value to you, and what level of quality you are seeking for you engine. Are you wanting the best you can have, -or is mediocre acceptable for your engine?

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Old 10-20-2020, 10:09 AM   #17
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Default Re: Time lapse Model A engine build

Ford turned their engines with large electric motors to bed them in. The motor circuit had a large amp meter that employees on the run in line would monitor to make sure that the current dropped to a specific range of amps that indicated that the engine was indeed ready for service and could be sent on to the different assembly lines there and around the country. This also gave them a chance to check for coolant system leaks and lubrication system function & leakage. If an engine took too many amps to turn or not enough then it was set aside for further repair evaluation.

I don't know how tight they were to start or what was considered acceptable but they undoubtedly had limitations to go by.

Most rebuilders set them up to where they can be started and run on a test stand to insure a unit will work for the customer. I'd say it was set up tighter than what most rebuilders would consider as normal if the starter wouldn't turn it over. Lubricant has to have a clearance to do it's job. The clearance should not have to be "opened up" by turning a crank in a too tight no clearance situation. The clearance can be kept to a minimum if proper machining practices are followed. Bedding in processes should smooth out minute high spots in a bearing surface rather than actually opening up a clearance that was not there to begin with.

I've seen so many reality TV productions that just have to add drama that I tend to avoid them like the plague whether they are about cars, motorcycles, or just life in general.

Last edited by rotorwrench; 10-20-2020 at 10:30 AM.
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Old 10-20-2020, 11:24 AM   #18
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Ford turned their engines with large electric motors to bed them in. The motor circuit had a large amp meter that employees on the run in line would monitor to make sure that the current dropped to a specific range of amps that indicated that the engine was indeed ready for service and could be sent on to the different assembly lines there and around the country. This also gave them a chance to check for coolant system leaks and lubrication system function & leakage. If an engine took too many amps to turn or not enough then it was set aside for further repair evaluation.

I don't know how tight they were to start or what was considered acceptable but they undoubtedly had limitations to go by.

Most rebuilders set them up to where they can be started and run on a test stand to insure a unit will work for the customer. I'd say it was set up tighter than what most rebuilders would consider as normal if the starter wouldn't turn it over. Lubricant has to have a clearance to do it's job. The clearance should not have to be "opened up" by turning a crank in a too tight no clearance situation. The clearance can be kept to a minimum if proper machining practices are followed. Bedding in processes should smooth out minute high spots in a bearing surface rather than actually opening up a clearance that was not there to begin with.

I've seen so many reality TV productions that just have to add drama that I tend to avoid them like the plague whether they are about cars, motorcycles, or just life in general.
I am going to add something that many do not understand about this process. When most crankshaft grinders resize a crankshaft, we are using a process call plunge grinding. Unlike a cylindrical grinder, we engage the grinder stone to the journal pin coming in 90 perpendicular, and once we have achieved the target size, we move the carriage over to the adjacent area of the pin and grind that to size. Although the quality of tooling has been improved over the years, the ability to make both cuts on the same journal equal the same number is beyond difficult at best. For my personal machine, if I can replicate a grind to a quarter-thousandth (0.00025"), then I am happy. Even if you hit the differential at a half-thousandth, your eye will see a faint line difference however your fingernail will likely never detect it. This differential is usually camouflaged by using a cork belt to blend the differences in sizing. So when the cast bearing is heated due to friction, it tends to become fluid in the tight areas and flows towards the looser clearanced areas. It really is not over-tightened as the clearances are probably around 0.00075" to 0.001" in certain areas. There is still oil clearance in the adjacent areas around the journal pin.
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Old 10-21-2020, 03:24 PM   #19
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Default Re: Time lapse Model A engine build

Some things I think the video skipped include pressure testing the block for cracks and the process for dialing in the alignment of the flywheel housing. Sealing up the oil pan and the gasket at the front is a process that is, in my opinion, glossed over. What else was not shown that should have?
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Old 10-22-2020, 10:53 AM   #20
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Just for my own edumication since I am not well versed in machining an engine. I just want to be clear that 'fluidizing' the bearings means setting the bearing clearance to basically zero and (via the electric motor) 'melting' or 'wearing' the bearings to the correct size using the crank? This way they don't have to cut the bearings to size? Maybe it is just the term that is throwing me off.



I also am assuming that this is the best way to set the bearings (if you can) so that each bearing matches its individual journal/rod?


Thanks


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Old 10-22-2020, 11:44 AM   #21
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I just want to be clear that 'fluidizing' the bearings means setting the bearing clearance to basically zero and (via the electric motor) 'melting' or 'wearing' the bearings to the correct size using the crank? This way they don't have to cut the bearings to size? Maybe it is just the term that is throwing me off.



I also am assuming that this is the best way to set the bearings (if you can) so that each bearing matches its individual journal/rod?


Thanks
Mike

Actually the bearings still need to be cut to size, but the burnishing method heats the casting only to the point where it becomes soft. This allows the bearing material to flow ever so slightly where it fits the journal pin with a closer tolerance. Additionally, the bearing material becomes harder after the process which increases the longevity of the bearing.






Hopefully you can read the information on these two pictures of a burnishing machine to better understand the process.

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Old 10-22-2020, 12:16 PM   #22
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Thanks Brent, this is very interesting. I wonder if anyone has figured out what duration and speed of "towing around a parking lot" is roughly equivalent to the 200 rpm burnishing operation they discuss in those pages. I guess you'd have to stop every X minutes and crank the engine by hand to try to sense when the force required had dropped enough.
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Old 10-22-2020, 05:34 PM   #23
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I'm not sure if Ford even peened the bearings after the babbitt was poured into the block. That may have been the purpose of the burnishing process. The crankshaft has a tendency to grow a good bit during that burnishing process due to heat generated. That would have made it problematic to even have the connecting rods attached prior to burnishing since the crank would grow too much and put them in a bind. The growth of the shaft would have been what set the clearance of the bearing and it would have insured the poured bearing would fit the block better since it's not really practical to tin a porous surface like a cast iron block even when new.

A lot of this stuff just wasn't done during rebuilding of engines outside the factory. Peening tools were mostly made for that side of the business in order to get the bearing to fit the block prior to align boring the bearings. Some of those peening tools look better than others for doing that job. There were also expandable rotary burnishing tools that were used by some in the rebuilding business. There was a lot of room for different tooling being used and different ideas about what procedures worked better than others. This leads to a lot of differing opinions on the subject.

All I know is that there weren't a lot of manufacturers doing engine bearings the same way that Ford was. Even Ford dropped babbitt bearing processes with the V8 LB engines in 1936.

This guy mentions the burnishing process in this link.
https://www.kmwford.com/what-is-a-babbitt.html

Last edited by rotorwrench; 10-22-2020 at 05:51 PM.
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Old 10-23-2020, 09:04 AM   #24
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I'm not sure if Ford even peened the bearings after the babbitt was poured into the block. That may have been the purpose of the burnishing process. The crankshaft has a tendency to grow a good bit during that burnishing process due to heat generated. That would have made it problematic to even have the connecting rods attached prior to burnishing since the crank would grow too much and put them in a bind. The growth of the shaft would have been what set the clearance of the bearing and it would have insured the poured bearing would fit the block better since it's not really practical to tin a porous surface like a cast iron block even when new.

A lot of this stuff just wasn't done during rebuilding of engines outside the factory. Peening tools were mostly made for that side of the business in order to get the bearing to fit the block prior to align boring the bearings. Some of those peening tools look better than others for doing that job. There were also expandable rotary burnishing tools that were used by some in the rebuilding business. There was a lot of room for different tooling being used and different ideas about what procedures worked better than others. This leads to a lot of differing opinions on the subject.

All I know is that there weren't a lot of manufacturers doing engine bearings the same way that Ford was. Even Ford dropped babbitt bearing processes with the V8 LB engines in 1936.

This guy mentions the burnishing process in this link.
https://www.kmwford.com/what-is-a-babbitt.html

I am not sure that is an accurate statement about the crankshaft growing quite a bit. My experience is that it grows the same as if it were in regular operation. The process of burnishing is to just barely tighten the cap nuts where the cap is barely rubbing. That is enough pressure to burnish the bearing. Since I cannot upload a video here, CLICK HERE to see if you can open this video that shows what is done, how much cap pressure, etc.


Tinning cast iron does nothing because the tin/solder will not stick to the cast iron. For that reason alone, Ford used holes to anchor the cast bearing to the cast block and or rear main cap.


The reason peening was not done at the factory is because the blocks were brought up to pour temperature in an oven prior to the pour, and were reintroduced into an oven for a slow post cool-down. Just like spin pouring connecting rods, in that production work allows processes for efficiency. Peening is necessary if you cannot keep the block hot enough to keep the cast bearing from prematurely shrinking.
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Old 10-23-2020, 09:28 AM   #25
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Wow, so much interesting info resulted from my basic question in Post 6. Quite a bit of it is over my head, but interesting anyway. I find it really interesting that processes/info used on 90 year old cars is still known. Thanks for sharing.
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Old 10-23-2020, 11:50 AM   #26
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Brent, thank you for posting the ad about the burnishing machine. I learned quite a bit-most of this is over my head as well-but I learned that even in the 20's there were full pressure oil systems and shell bearings. I am guessing on the more expensive cars.

But, if burnishing the main bearings is more accurate than line boring I am surprised nobody has come up with an interesting way to recreate a burnishing machine. I am assuming it can be done with modern parts in a shop. Whether it is cost effective for a small time shop I don't know, but for a bigger shop?

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Old 10-23-2020, 12:04 PM   #27
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If you check out the video link in Brent's post, it's basically a burnishing machine, though less fancy.
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Old 10-23-2020, 12:43 PM   #28
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But, if burnishing the main bearings is more accurate than line boring I am surprised nobody has come up with an interesting way to recreate a burnishing machine. I am assuming it can be done with modern parts in a shop. Whether it is cost effective for a small time shop I don't know, but for a bigger shop?
Just so we are clear Mike, the bearings still must be line-bored as a way to ensure all three are coplanar. What the burnishing is doing is making the surface area of the bearing be closer in the dimension and shape of the crankshaft's journal.

Alternately to burnishing, the bearing clearances can be taken up by removing shims after running the engine 'XX' (-i.e.: small) amount of miles. The definition of 'XX' is different depending on the quality of the line-boring job and/or the Babbitt material composition. After operating the engine for the 'XX' period of time, the bearing clearances can be adjusted because the wear during that period has provided more contact area of the bearing against the journal pin. The time between the next adjustment period will/should be longer since there is now more bearing surface contact area to support the crankshaft.

There are still custom engine rebuilders that do still burnish bearings. Some do have specially-made machines that do the burnishing. I know of three or four creations that work very well.

Remember, the downside to this procedure is that it takes additional time. Time is money for most shops (-and most Model-A customers tend to be frugal ). The upside to doing this procedure is the bearing is denser and the contact area is much greater which adds longevity. It is very feasible for the first bearing clearance adjustment to be done at the 20k-25k mileage mark. Because of the babbitt density and thickness, with prudent driving habits (-no detonation, proper oil change intervals, etc.) a babbitted engine can outlast an inserted bearing twice-fold.
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Old 10-23-2020, 12:54 PM   #29
BRENT in 10-uh-C
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Default Re: Time lapse Model A engine build

Quote:
Originally Posted by 30 Closed Cab PU View Post
Wow, so much interesting info resulted from my basic question in Post 6. Quite a bit of it is over my head, but interesting anyway. I find it really interesting that processes/info used on 90 year old cars is still known. Thanks for sharing.
It really is a simple comparison. If you look at the picture of the burnishing machine, you can see there is a heavy flywheel mass on the opposite end of the machine from the block. The machine uses the energy stored to rotate the crankshaft when the bearings are tight. Alternately, by towing the vehicle with the engine spinning, the energy transferred thru towing it is greater than what the starter s capable of generating.

One key part that I failed to mention, in that 3rd or 4th paragraph of the flyer, it speaks of how the mechanic can achieve 95%-100% of bearing contact. In other words, its like the difference between 100 men carrying a load vs 75 men. 100 men can likely do it much easier and for a much longer period than the 75 men can.
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Old 10-23-2020, 02:58 PM   #30
rotorwrench
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Default Re: Time lapse Model A engine build

A lot of folks that do Model A and T engines don't burnish them like Ford did. They peen the bearings after they are poured to get them to fit well against the block then they align bore them to size. Ford was manufacturing more engines in a day than most folks work on in a year. Ford found their best way of building them as quickly as possible. Ford also had equipment that is unobtainium in this day and age. It takes longer to peen each bearing and prep for boring or reaming of the bearings but that is a practical way of doing things in the current business scheme of things. Some crankshafts have less meat on them now days so that takes more bearing babbitt to fill that gap. The thicker the babbitt gets may make the job a bit more complex than having nice new standard size parts to work with. A person could also use Time Saver lapping compound with a turning machine like the aftermarket unit in the brochure. The Time Saver compounds have been around since the model T days and have always been guaranteed to leave no abrasive embedded in the bearing surface.

On the subject of burnishing, I mentioned before that I don't know what the fit was at Ford when they were ready to start that process but I assume that is is safe to say that there likely wasn't much clearance in any of the mains when they started turning for the process. That shaft is going to heat up a way lot more with little or no clearance than a shaft journal with 0.0015" clearance. A properly lubricated bearing with 0.0015" of clearance will run relatively cool. One with no clearance and even with some oil for lubricant will damn sure get hot. The hotter it gets, the more that shaft will grow in every direction. The growth of the shaft is what forces the bearing material outward against the block and the main cap. The heat would cause the increase in plasticity of the babbitt and allow it to gain more clearance. How much clearance could be gained that way depends on how hot it gets and how much plasticity will occur without damaging the bearing. I have no idea what they actually ended up with for clearance. Ford had something figured out for that since they managed to manufacture multiple millions of these engines in the four years of production and likely a few thousand more after production stopped since they were produced up into the 40s for ag and industrial applications.

Last edited by rotorwrench; 10-23-2020 at 04:57 PM.
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Old 10-23-2020, 03:04 PM   #31
Jeff/Illinois
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Default Re: Time lapse Model A engine build

Interesting video fun to watch, thanks!

Also thanks for the info from posters on burnishing the bearings. I was especially interested in the fact that a PROPERLY done Model A with Babbitt bearings can and will outperform an insert bearing engine. Cool!
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