Bye-bye flywheel

Discuss all things Model T related.
Forum rules
If you need help logging in, or have question about how something works, use the Support forum located here Support Forum
Complete set of Forum Rules Forum Rules
User avatar

Topic author
Oldav8tor
Posts: 1928
Joined: Sun Jan 06, 2019 11:39 am
First Name: Tim
Last Name: Juhl
* REQUIRED* Type and Year of Model Ts owned: 1917 Touring
Location: Thumb of Michigan
MTFCA Number: 50297
MTFCI Number: 24810
Board Member Since: 2018

Bye-bye flywheel

Post by Oldav8tor » Fri Jun 24, 2022 8:41 pm

When a engine rebuilder starts a conversation saying "I've never seen one this bad" you know it isn't going to be good news. My '17 touring has 5400+ mostly trouble-free miles on it since August of 2019. The engine is strong and the transmission worked smoothly and ran quietly. Reverse was never as smooth as low but it did what I needed it to do.

Two weeks ago I drove to my county's museum complex to give a few rides. Driving to my usual spot I found an obstacle in the way and decided I needed to back up a bit and turn the car around. The grassy yard was a little soft and there was a slight incline. I pressed the reverse pedal but the car wouldn't move. Tried again and this time heard some noises and upon releasing the reverse pedal, the car lurched forward and stalled. I was able to get it started an nursed it home where I started looking for the problem. Things looked normal but acting on the advice of my engine rebuilder, I tightened the reverse band a turn, stepped out and turned the hand crank. When I did so, the car moved forward.... Taking another look at the drums, I found a hairline crack on the reverse drum so the engine was coming out. With the help of friends, we had it out and on a trailer by ten pm that same night.

I took the engine / transmission back to the rebuilder to investigate the problem. When they tore it down, they found that the triple gear pins had apparently loosened with the result that the holes in the flywheel were elongated, rendering it scrap. The triple gears, shaft and reverse drum were junk as well, and I chose to replace them all with new. I also asked them to inspect the engine itself while they had the oil pan off.

Today I picked the engine up. Before loading it on the trailer they ran it on a dyno where it performed and sounded great. The engine inspection showed it to be "like new" so at least I did something right. The rebuilders don't really know what caused my transmission problems. I discussed my driving techniques, etc., but they couldn't see how anything I'd done could have caused this.

Has anyone else had a similar experience? Do you know what caused it? Any operational suggestions?
flywheel.jpg
1917 Touring
1946 Aeronca Champ
1952 Willys M38a1 Jeep (sold 2023)
1953 Ford Jubilee Tractor


Scott_Conger
Posts: 6428
Joined: Sun Jan 06, 2019 11:18 am
First Name: Scott
Last Name: Conger
* REQUIRED* Type and Year of Model Ts owned: '13, '15, '19, '23
Location: Clark, WY
Board Member Since: 2005

Re: Bye-bye flywheel

Post by Scott_Conger » Fri Jun 24, 2022 8:50 pm

Triple gear bushings too tight on the pins as fitted during rebuild
Scott Conger

Tyranny under the guise of law is still Tyranny

NH Full Flow Float Valves
Obsolete carburetor parts manufactured


Dan Hatch
Posts: 4110
Joined: Tue Jan 08, 2019 7:31 pm
First Name: Dan
Last Name: Hatch
Location: Alabama
MTFCA Number: 49974

Re: Bye-bye flywheel

Post by Dan Hatch » Fri Jun 24, 2022 9:01 pm

This may have been the second set of pins for this flywheel. Holes too big for replacement pins. Have seen it before. Dan


Allan
Posts: 5201
Joined: Sun Jan 06, 2019 7:21 pm
First Name: Allan
Last Name: Bennett
* REQUIRED* Type and Year of Model Ts owned: 1912 van, 1917 shooting brake, 1929 roadster buckboard, 1924 tourer, 1925 barn find buckboard, 1925 D &F wide body roadster, 1927LHD Tudor sedan.
Location: Gawler, Australia

Re: Bye-bye flywheel

Post by Allan » Fri Jun 24, 2022 9:18 pm

One triple gear bush was obviously too tight a fit and seized on the pin. That may also have been the case on the flogged out one too. If the pins had been replaced at the same time as the bushes, the holes in the flywheel may also have been compromised.

What clearance in the bushes have others found to be satisfactory? Can we speak in pin diameters and bush hole diameters to get around running clearance understandings.

Allan from down under.

User avatar

Mark Chaffin
Posts: 3327
Joined: Sat Jan 12, 2019 12:11 pm
First Name: Mark
Last Name: Chaffin
* REQUIRED* Type and Year of Model Ts owned: 1911 Speedster, 1927 Lake Roadster
Location: Lake Elsinore
MTFCA Number: 31705
Board Member Since: 2001

Re: Bye-bye flywheel

Post by Mark Chaffin » Fri Jun 24, 2022 9:25 pm

Totally agree with Scott's assessment. Not enough clearance between the tripple gear bushings and pins. I have rebuilt many transmissions and have always set them on the loose side of .0025 to .003 running clearance and have never had a pin / bushing failure. .005 to .006 overall clearance on the bushing for those who don't like the term running fit. :)


Erik Johnson
Posts: 850
Joined: Mon Feb 04, 2019 10:25 pm
First Name: Erik
Last Name: Johnson
Location: Minneapolis, MN

Re: Bye-bye flywheel

Post by Erik Johnson » Fri Jun 24, 2022 11:21 pm

Would an original 1917 flywheel have a Ford script on it?

User avatar

Steve Jelf
Posts: 6463
Joined: Fri Jan 04, 2019 9:37 pm
First Name: Steve
Last Name: Jelf
* REQUIRED* Type and Year of Model Ts owned: 1923 touring and a few projects
Location: Parkerfield, Kansas
MTFCA Number: 16175
MTFCI Number: 14758
Board Member Since: 2007
Contact:

Re: Bye-bye flywheel

Post by Steve Jelf » Fri Jun 24, 2022 11:22 pm

My 1923 transmission disaster included a broken low drum and a seized triple gear bushing. The flywheel was toast, of course. I don't know whether one failure caused the other, or they were coincidentally simultaneous.
The inevitable often happens.
1915 Runabout
1923 Touring


Wayne Sheldon
Posts: 3637
Joined: Sun Jan 06, 2019 3:13 pm
First Name: Wayne
Last Name: Sheldon
* REQUIRED* Type and Year of Model Ts owned: 1915 Runabout 1913 Speedster
Location: Grass Valley California, USA
Board Member Since: 2005

Re: Bye-bye flywheel

Post by Wayne Sheldon » Sat Jun 25, 2022 2:42 am

I also like those on the loose side of recommended. Modern machinists are trained (I took the classes fifty years ago and this was their approach then!) to believe that everything needed to be the most perfect tightest fit that can possibly work to be any good at all. OLD machinery often doesn't like anything too tight. Their cogs and cams like to bounce around a bit and routine messy lubrication needs to work its way in and around loose bushings. I have personally seen a dozen model Ts rebuilt and set up by so-called experts (NOT naming names!) with seized triple gear bushings! I usually find ones plenty good for me to use. In rare cases where I have had new bushings installed? I check them and refit them myself.

My experience with one like yours? Not quite, but almost as bad as yours.
I was doing one of my "resurrection from the jaws of the soil reclaiming an original model T speedster", which meant piecing together a lot of missing parts. The original body was shaping up okay, and the chassis was coming along nicely. I had a correct year engine I wanted to use, but it need a bit more work than I was prepared to do right then.
I had a really tired old T engine (long block), and a used transmission that looked alright. I bolted the two together, put on a pan and hogshead along with newly lined bands, and installed in the chassis. Soon after, the car was unfinished, but running and drivable.
That tired old engine was really tired. The car could do 42 mph all day long, and do just fine. 43 mph, and the blow-by increased enough (blew off and lost TWO oil filler caps!) to make the engine go to a full boil in a couple miles! Hot gasses circling the crankcase inside does heat things up!
The transmission? Was the sweetest, most quiet, smooth moving model T transmission I ever drove or heard! I drove the car that way for about three years, put a couple thousand miles on it. But that blow-by was annoying, so I reworked the proper engine, and fixed it up nice. I had originally intended to leave the entire temporary engine together as a ready spare. But that transmission was SO-O nice! So I pulled the old engine out of the car, and began to split it apart. I had the engine hanging on a chain, removed the hogshead and pan, and prepared to separate the flywheel from the crankshaft. Turned out, the transmission drums were turned just right, a tink, a clunk, and couple clatters, and two triple gear pins fell OUT and landed on the concrete! Along with one gear!
I knew my plans had just changed. I got the transmission apart. Two triple gear pins had seized into their bushings and wore themselves loose from the flywheel. The small shoulders of the pins fell through the worn oversize holes. The worst one was just about half as large as the big hole you showed. One of the bushings and pins came apart on its own. The other one? I never did get it apart, they just fell out as one. The third one chewed up the bushing and inside of the gear.
The low drum had been scored (before I used it with wood bands because the score wouldn't hurt the wood like it would have a woven lining). So by the time I checked everything out? There were only a few parts that were actually any good, mainly, the clutch was okay.
How that mess could have run so nicely is something I may never understand. Maybe all those loose pieces just floated along on faith?

How much longer might it have gone? Don't know. However, in retrospect, I was glad I decided to take it apart and use the transmission and discovered it was junk rather than leave it together to leave me stranded somewhere later in another car.


Allan
Posts: 5201
Joined: Sun Jan 06, 2019 7:21 pm
First Name: Allan
Last Name: Bennett
* REQUIRED* Type and Year of Model Ts owned: 1912 van, 1917 shooting brake, 1929 roadster buckboard, 1924 tourer, 1925 barn find buckboard, 1925 D &F wide body roadster, 1927LHD Tudor sedan.
Location: Gawler, Australia

Re: Bye-bye flywheel

Post by Allan » Sat Jun 25, 2022 2:58 am

Thanks Mark. I have always used .005" as the pin to bushing fit, and have had no trouble as yet.
The transmission in my 1917 shooting brake is entirely original. i selected it because it had a virgin ring gear so i could fit a starter later on. The reverse drum was so little used I could still see traces of the original ground surface. I still tore it down to check all the bushings. Those original triple gear bushings were sized .0045" to .005" I balanced the assembly and put it back together as a unit, and it is the nicest T transmission I have ever had the pleasure to drive.

Allan from down under.

User avatar

Topic author
Oldav8tor
Posts: 1928
Joined: Sun Jan 06, 2019 11:39 am
First Name: Tim
Last Name: Juhl
* REQUIRED* Type and Year of Model Ts owned: 1917 Touring
Location: Thumb of Michigan
MTFCA Number: 50297
MTFCI Number: 24810
Board Member Since: 2018

Re: Bye-bye flywheel

Post by Oldav8tor » Sat Jun 25, 2022 10:38 am

The guys who put the engine together in 2018 and fixed it for me now are very aware of the need to avoid a too-tight bushing to pin fit and quoted the same clearances that Mark Mentioned. They've been rebuilding Model T engines for decades and this is the first one they've gotten back that was this bad.

All of the suggestions you fella's put forward make sense. I don't think I'll ever know for sure what specifically happened here. Question, is there a good way you can check for developing problems through the opening in the hogshead? I have a transmission filter which gets cleaned at least every oil change so the cover comes off. One thing I noticed this last time was fine brass "dust" and a couple of brass turnings in the filter. I'm guessing if I start to see brass again that there may be a problem with a bushing somewhere in the tranny and inspection is warranted. Comments?
1917 Touring
1946 Aeronca Champ
1952 Willys M38a1 Jeep (sold 2023)
1953 Ford Jubilee Tractor


speedytinc
Posts: 3838
Joined: Fri Feb 12, 2021 12:24 pm
First Name: john
Last Name: karvaly
* REQUIRED* Type and Year of Model Ts owned: 14/15 wide track roadster. 23 touring, 27 roadster pickup, 20ish rajo touring
Location: orange, ca
MTFCA Number: 14383
Board Member Since: 2020

Re: Bye-bye flywheel

Post by speedytinc » Sat Jun 25, 2022 11:23 am

"All of the suggestions you fella's put forward make sense. I don't think I'll ever know for sure what specifically happened here. Question, is there a good way you can check for developing problems through the opening in the hogshead? I have a transmission filter which gets cleaned at least every oil change so the cover comes off. One thing I noticed this last time was fine brass "dust" and a couple of brass turnings in the filter. I'm guessing if I start to see brass again that there may be a problem with a bushing somewhere in the tranny and inspection is warranted. Comments?"

The brass dust is a sign. The tripple gears get the most abuse & are going to wear the quickest & fail first. Previous assessments on too tight bushing clearance and/or replaced loose pin clearance causing your failure sound right. Cant tell from your picture, but, the pin hole press can create a crack into that nearest magnet mounting hole. That one spot is the most vulnerable.

When one notices different/louder tripple gear noise, thats a wear issue. One can check the condition of the tripple gear wear/mesh with a large screwdriver thru the HH cover. The key here is to do the repair before the tripple gear problems take out much more expensive parts.( dont ignore increasing noises.)

User avatar

Topic author
Oldav8tor
Posts: 1928
Joined: Sun Jan 06, 2019 11:39 am
First Name: Tim
Last Name: Juhl
* REQUIRED* Type and Year of Model Ts owned: 1917 Touring
Location: Thumb of Michigan
MTFCA Number: 50297
MTFCI Number: 24810
Board Member Since: 2018

Re: Bye-bye flywheel

Post by Oldav8tor » Sat Jun 25, 2022 4:23 pm

Excellent suggestions. Funny thing, maybe I’m going deaf but my transmission was quiet right up to the failure. It was an expensive education for me but I’ve added checking the gears to the list of routine maintenance. I’m also going to take a much closer look at the flywheel and other “remains” to see if there are any more clues to “why” or “how”?
1917 Touring
1946 Aeronca Champ
1952 Willys M38a1 Jeep (sold 2023)
1953 Ford Jubilee Tractor


speedytinc
Posts: 3838
Joined: Fri Feb 12, 2021 12:24 pm
First Name: john
Last Name: karvaly
* REQUIRED* Type and Year of Model Ts owned: 14/15 wide track roadster. 23 touring, 27 roadster pickup, 20ish rajo touring
Location: orange, ca
MTFCA Number: 14383
Board Member Since: 2020

Re: Bye-bye flywheel

Post by speedytinc » Sat Jun 25, 2022 6:34 pm

Its a safe bet to blame tight tripple gear bushings. Once they seize they are going to take out the next weakest piece. If the bushings were set tight or locked into the gear, when the pin to bushing fit locks, that bushing to gear cant give in to become the new running surface, which is a common find.
With the 2 tripple bushing surfaces locked, the problem went to a slightly loose pin hole, which probably would not have failed otherwise.


J1MGOLDEN
Posts: 944
Joined: Sun Jan 06, 2019 5:39 pm
First Name: James
Last Name: Golden
* REQUIRED* Type and Year of Model Ts owned: 1926 Model T Roadster
Location: Bowie, MD
MTFCA Number: 14294
MTFCI Number: 13562

Re: Bye-bye flywheel

Post by J1MGOLDEN » Sat Jun 25, 2022 7:46 pm

That happened to me about 20 years ago.

There were complaints at that time about a different combination of te bushing materials that made them swell when hot and not shrink again when cold.

This one just tore into.
Attachments
Peg Problem.JPG
Peg Problem.JPG (79.62 KiB) Viewed 2716 times

User avatar

Topic author
Oldav8tor
Posts: 1928
Joined: Sun Jan 06, 2019 11:39 am
First Name: Tim
Last Name: Juhl
* REQUIRED* Type and Year of Model Ts owned: 1917 Touring
Location: Thumb of Michigan
MTFCA Number: 50297
MTFCI Number: 24810
Board Member Since: 2018

Re: Bye-bye flywheel

Post by Oldav8tor » Sat Jun 25, 2022 8:46 pm

I've heard from others that a few years ago some bushings hit the market that had a different alloy blend that allowed them to expand excessively and lock on the pin as others suggested. That's the most logical explanation I've heard so far. It is obvious to me that the pin was loose and spinning. How else can you explain the damage?
1917 Touring
1946 Aeronca Champ
1952 Willys M38a1 Jeep (sold 2023)
1953 Ford Jubilee Tractor


Dan Hatch
Posts: 4110
Joined: Tue Jan 08, 2019 7:31 pm
First Name: Dan
Last Name: Hatch
Location: Alabama
MTFCA Number: 49974

Re: Bye-bye flywheel

Post by Dan Hatch » Sat Jun 25, 2022 9:38 pm

If you use the pins from most vendors and don’t polish them the bushings will lock up. The finish is not smooth enough. Look up an old post from Herm. He showed this years ago.
Also check the size of pin in flywheel. As I said, if it already has had pins replaced the new pins will not stay tight in flywheel. Seen it before.
And ball sizing the bushings instead of reaming will make bushings not slip in gear.

User avatar

Topic author
Oldav8tor
Posts: 1928
Joined: Sun Jan 06, 2019 11:39 am
First Name: Tim
Last Name: Juhl
* REQUIRED* Type and Year of Model Ts owned: 1917 Touring
Location: Thumb of Michigan
MTFCA Number: 50297
MTFCI Number: 24810
Board Member Since: 2018

Re: Bye-bye flywheel

Post by Oldav8tor » Sun Jun 26, 2022 9:07 pm

Thanks to all of you who have shared your experiences and observations. I finally found time to drag the damaged triple gears out of the box and look them over more closely. It is obvious that the bushings locked upon the pins. It appears that the gears were spinning on the bushings (and eventually spinning at least two of the pins). I have to wonder just how long this was going on before it failed? All seemed to be fine until I tried to back up a little incline and something let loose.

I never suspected such a thing was a problem with Model T's but from the other postings I see that it is more common than I would have thought. My confidence in the car has dropped a few notches and I suspect I'll be listening very carefully to any new noises the car makes.

I've attached a better photo of the flywheel and the triple gears. Two of the pins spun out, one of the gears game off the bushing which is locked to the pin.
Flywheel2.jpg
1917 Touring
1946 Aeronca Champ
1952 Willys M38a1 Jeep (sold 2023)
1953 Ford Jubilee Tractor

User avatar

Topic author
Oldav8tor
Posts: 1928
Joined: Sun Jan 06, 2019 11:39 am
First Name: Tim
Last Name: Juhl
* REQUIRED* Type and Year of Model Ts owned: 1917 Touring
Location: Thumb of Michigan
MTFCA Number: 50297
MTFCI Number: 24810
Board Member Since: 2018

Re: Bye-bye flywheel

Post by Oldav8tor » Tue Jun 28, 2022 4:58 pm

Carole King's song "You've got a Friend" applies to the times in the Model T world when you can use some help. A little over two weeks ago the flywheel under discussion above finally gave up the ghost, setting into motion an extraordinary series of events, all aimed at helping me get back on the road. I am truly humbled to have friends who are there when I need them, and wish to acknowledge them here

The list is pretty long but Charlie Volkening and Tom Graham rebuilt my transmission and checked over my engine in record time. Don Booth served as a way-station in getting my engine to the North Country to be rebuilt. Dave Nolting who trusted someone he'd never met enough to ship out a set of new drums before he received my check so that I wouldn't be held back waiting for them. Denny Newman shared his knowledge and advice on a couple of issues that could have developed into additional troubles. Gene Butler has been there for every step of the process as has Brian Dowell who provided much of the tools, expertise and energy to get the job done. Tony Osentoski, Ron Stratton and Wayne Lepola did not hesitate to get greasy and lend a hand where needed.

The result? The engine is back in the car and I am in the process of hooking things back up and getting ready for a road test and further adjustment. Thanks to all who helped, I hope I can be as good a friend to you......
Wayne, Gene and Brian making sure the engine goes in smoothly. Ron is underneath fitting the universal into the engine
Wayne, Gene and Brian making sure the engine goes in smoothly. Ron is underneath fitting the universal into the engine
Wayne and Ron working on the hard to get to bolts
Wayne and Ron working on the hard to get to bolts
Last edited by Oldav8tor on Tue Jun 28, 2022 9:16 pm, edited 1 time in total.
1917 Touring
1946 Aeronca Champ
1952 Willys M38a1 Jeep (sold 2023)
1953 Ford Jubilee Tractor


Jerry VanOoteghem
Posts: 2946
Joined: Sun Jan 06, 2019 4:06 pm
First Name: Jerry
Last Name: Van
Location: S.E. Michigan
MTFCA Number: 24868

Re: Bye-bye flywheel

Post by Jerry VanOoteghem » Tue Jun 28, 2022 6:22 pm

Tim,

You had a "dream team" on your side for sure! Happy to see you're nearly back on the road. :)


TXGOAT2
Posts: 6411
Joined: Sun Feb 14, 2021 10:08 pm
First Name: Pat
Last Name: McNallen
* REQUIRED* Type and Year of Model Ts owned: 1926-7 roadster
Location: Graham, Texas
MTFCA Number: 51486
Board Member Since: 2021

Re: Bye-bye flywheel

Post by TXGOAT2 » Tue Jun 28, 2022 10:33 pm

I wonder if modern "lead-free" bushings contribute to this problem. I'd think brass with some lead content would be less likely to seize at the Ford spec. Pin hardness and finish could also have an effect. I wouldn't think that the pin becoming loose in the flywheel would cause the bushing to seize, but I suppose it might. Chicken, or egg?


TXGOAT2
Posts: 6411
Joined: Sun Feb 14, 2021 10:08 pm
First Name: Pat
Last Name: McNallen
* REQUIRED* Type and Year of Model Ts owned: 1926-7 roadster
Location: Graham, Texas
MTFCA Number: 51486
Board Member Since: 2021

Re: Bye-bye flywheel

Post by TXGOAT2 » Tue Jun 28, 2022 10:37 pm

... Looks like another reason to avoid winding it out in low.

User avatar

Topic author
Oldav8tor
Posts: 1928
Joined: Sun Jan 06, 2019 11:39 am
First Name: Tim
Last Name: Juhl
* REQUIRED* Type and Year of Model Ts owned: 1917 Touring
Location: Thumb of Michigan
MTFCA Number: 50297
MTFCI Number: 24810
Board Member Since: 2018

Re: Bye-bye flywheel

Post by Oldav8tor » Wed Jun 29, 2022 10:55 am

My triple gear bushings were firmly seized to the pins. I too wonder about the metallurgy of the bushings available today. It's like they expanded with heat and stayed that way, perhaps thru multiple cycles.

The kind of driving I do should be easy on the triple gears - very little stop-and-go, little need to use reverse and long runs at modest speed in high. Quite frankly I am perplexed to understand why this happened. I also suspect that it was probably going on for some time. You'd think that the transmission would have gotten real noisy but until the "final failure" everything seemed fine. You can bet I'll be listening for every little noise now... kinda like when flying a single-engine airplane across a wide expanse of water.... every little noise gets your attention.
1917 Touring
1946 Aeronca Champ
1952 Willys M38a1 Jeep (sold 2023)
1953 Ford Jubilee Tractor


Dan Hatch
Posts: 4110
Joined: Tue Jan 08, 2019 7:31 pm
First Name: Dan
Last Name: Hatch
Location: Alabama
MTFCA Number: 49974

Re: Bye-bye flywheel

Post by Dan Hatch » Wed Jun 29, 2022 11:42 am

At one time there were two “grades” of triple gear bushings offered. The better grade was made with an alloy that was suppose to be same as Ford. I just noticed that now there is only one.
Also, if you look at some reproduction pins there is no shoulder on them. Not like a Ford pin. Only one source has the shoulder, this is to keep pin from coming through the flywheel.

Also finish on only one pin maker is correct, unless this has changed in last few years.
Last edited by Dan Hatch on Wed Jun 29, 2022 1:47 pm, edited 1 time in total.


Jerry VanOoteghem
Posts: 2946
Joined: Sun Jan 06, 2019 4:06 pm
First Name: Jerry
Last Name: Van
Location: S.E. Michigan
MTFCA Number: 24868

Re: Bye-bye flywheel

Post by Jerry VanOoteghem » Wed Jun 29, 2022 12:14 pm

Might be interesting to check the hardness of each pin. The worst looking one has the corners rolled over, which is really odd. Can't imagine a hardened pin doing that. Wonder if they were through-hardened or case hardened...

User avatar

George Mills
Posts: 543
Joined: Sun Jan 06, 2019 12:32 pm
First Name: George
Last Name: Mills
* REQUIRED* Type and Year of Model Ts owned: 1915 Roadster, 1919 Hack, 1925 Fordor
Location: Cherry Hill NJ/Anona Largo FL
MTFCA Number: 29497
MTFCI Number: 10032
Board Member Since: 1999

Re: Bye-bye flywheel

Post by George Mills » Wed Jun 29, 2022 12:59 pm

Jerry,

When everyone was doubling down about a dozen years ago on what was right and what wasn’t, the late Ralph Ricks and I had an idea. Collect up dozens and dozens of used bushes and pins, have them marked in such a way that further testing would keep them matched, and keep them blind, and then since I had access to 1) a mass spec analizer, 2) had a complete metalography lab, 3) Had techs and apprentices that were drooling to get at old iron in the lab, and 4 I own the former Humber UK tech library on Model T skunk work the Humber did….

The first thing we determined that was true was the John Regan was right all along…less than 10% of the pins were Ford metallurgy! As John stated and warned, through the years it was real common to replace pins with whatever the shop had laying around. So much so that after 100 years, our samples only had 10% genuine Ford parts.

As far as hardness and case, never went that far, only did Rockwell test in the lab.

We never got around to publishing the results…shared a draft with maybe 10 folks for comment and they all took umbrage at something in the findings…and for those who worked with Ralph on things, know that he never doubled down until completely proven 100% otherwise. We never got back to it and then Ralphie got sick.

If I can find it Jerry, I’ll share with you hardness numbers and finishes. At the time we did this we also tossed the (apparently two source) pins and while both satisfied the original print and tolerance, the ones from Don were perfect and super-accurate in any metric checked.

The bushing questions we are stuck with as Z never made it into the SAE system. I’m still waiting for an engineer much smarter that me to explain WHY Ford was so critical on oil groove depth and ‘no sharp corners’ that had AN OFF CENTER Linearly helix to the degrees and seconds call out. I have a hunch why, but my reasoning would be laughable….

Post Reply Previous topicNext topic