When did Ford change from crankshaft slingers to seals?

[glennpm]

Hi,

38_couupe and I are asking for help in identifying when Ford changes from front and rear crankshaft oil slingers to rope seals? I'd like to add a row to the chart below, adding this detail. this question was raised in this recent thread.

"Both of my 41s ( very early 3 piece fender ) have slingers and no rope seal . I also thought that the rope seal started in 42 . Memory gets slim in the later part of the day . Maybe its the coffee that wakes up mu memory?
As far as the work you want to do , some questions . How old are you ? Are you capable of doing the work yourself ? Are there known good flathead mechanics and machine shops around you ?
Are you aware of the difference between a slinger and a rope seal ? Check out what a slinger is if you didn’t.
Good luck, Gary" (Ggmac)

[Ken/Alabama]

Starting in 1939 with the 91A-6303-B and the 99A-6303-B crankshafts for big trucks and buses. The 6303-A crankshafts have the slinger on the rear used in the passenger car.

[Ggmac]

Joe Abbin , Ford and Mercury flathead v-8 identification abd rebuilders guide , page2-10
“ Sometime in 1941 , the slinger ( labyrinth) type rear main bearing oil seal ( used previously) was replacedby a rope seal on engines for commercial ( bus , truck ) applications. The rope type seal and associated parts became standard for all applications after the war . “

[Ggmac]

There is an easy way to tell if you have the slinger especially if its time for an oil change . Make sure your oil is at the full mark and on level ground . Add 3 1/2 to 4 1/2 qts of old oil and see if it streams out the back . Do not start it with this much oil in it . Drain oil .
I did this with a used motor I was going to buy , the seller said the 221 with bottom welch plug bumps , said the crank was machined and a rope seal was installed . Motor was supposed to only have 5,000 miles since rebuild. Well I didn’t buy it , oil poured out the back . I’m of the nature that if you lie to me about one thing , how much more is bs ?
A friend later bought the motor and was given the same story , long story but it still had the slinger and wasn’t rebuilt with only 5,000 miles on it . Maybe 30,000 . Major ridge and pistons at 040 .

[38 coupe]

I'll expand the question a bit. Let's make a list of all the crankshafts that fit the 221-239-255 flathead V8s. Off the top of my head I can think of:

• 1932, forged, short snout, 1.999 mains and rods
  • could have slinger ground down to make seal surface
• 1933-1936, cast, short snout, 1.999 mains and rods
  • could have slinger ground down to make seal surface
• 1936-1938, short snout, 2.399 mains and 1.999 rods
  • could have slinger ground down to make seal surface
• 1939-???, long snout, 2.499 mains and 1.999 rods, with slinger (221 motor crank)
  • could have slinger ground down to make seal surface
• ???-1942 (or some time in WW2), long snout, 2.499 mains and 1.999 rods, with rope seal (221 motor crank)
• 1939-???, long snout, 2.499 mains and 2.139 rods, with slinger (239 motor crank)
  • could have slinger ground down to make seal surface
• ???-1948, long snout, 2.499 mains and 2.139 rods, with rope seal (239 motor crank)
• 239 crank with rods ground off center to 1.999 journal get 3 7/8 stroke
• 1949-53 3 3/4 stroke Ford crank (239 motor crank)
• 1949-53 4 stroke Mercury crank (255 motor crank)
• 255 crank with rods ground off center to 1.999 journal to get 4 1/8 stroke
• Weird German long snout crank with 2.399 mains and 1.999 rods (unless my memory is wrong)
• Scat 4 stroke crank
• Scat 4 1/8 stroke crank
• Scat 4 1/4 stroke crank

I can't remember if the crankshaft ends were changed for 1951 when the automatic transmissions came out. What am I missing from the list?

[glennpm]

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Great question 38_coupe which would make a great addition to the engine table.

Glenn

[Bored&Stroked]

There are at least two different flywheel flanges for the later 51 - 53 crankshafts - one takes a throw-out bearing (like the 32 - 48 cranks), the other is for an automatic transmission (much smaller pilot hole).

I've not screwed with the automatic version, I'm sure they can be "retrofitted" for a clutch setup with a bit of work. Anybody know the deal on these?

[Mart]

You can never rule out previous rebuilds where older parts are fitted into newer blocks or vice versa. I was surprised to see a slinger crank in a 59 block for instance. It may have been correct, I don't know.

[38bill]

Same here. My 59A had a slinger that I became aware of when I tilted the motor during removal and oil poured out the back. Surprise! I had thought it would be easier to drain the crankcase once it was out of the truck.

[glennpm]

Thanks for everyone's comments!

I put together a document based on comments here and internet searches.
I also added it to the Techno-Source link, page #61, in my signature below.

Glenn

[Bored&Stroked]

Thanks Glen - UR the best!

[glennpm]

Originally Posted by Bored&Stroked

Thanks Glen - UR the best!

Thanks!