The Ford Barn

marty in Ohio · 05-22-2019, 06:11 AM

We're putting together the best parts of two engines (one a '29 and one a '31) to make one good one. When we tried to bolt on the rear main, the bolts were too long. Finally found in the Les Andrews book (page 137) that two different rear main caps were used. On one the boss was 9/16" tall and the other was 1-1/8" tall. The bolts were 3-5/8" and 4-3/16" respectively. Why the difference, and when did the change take place? Are they interchangeable except for this difference?
Marty

Kurt in NJ · 05-22-2019, 06:19 AM

The thinner one is a forged steel cap, thicker one cast iron, interchangeable with correct bolts
The forged cap cost more to make. I think the change happened in 1929, would have to look in service bulletins to get exact time

marty in Ohio · 05-22-2019, 05:56 PM

Thanks Kurt. Been playing with this car for over 25 years and I never knew there was a difference.
Marty

Bob Bidonde · 05-23-2019, 10:49 AM

The 1931 cylinder block has improvements over the 1929 block. The forged bearing cap is superior to the cast bearing cap in durability (fatigue life).

Dan McEachern · 05-26-2019, 10:50 PM

I like the steel cap because I can tin it rather than use just anchor holes to retain the babbit. I think it makes for a better babbit job.

Railcarmover · 05-27-2019, 11:34 AM

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Are your pouring bearings as part of your services Dan?

05-22-2019, 06:11 AM	#1
marty in Ohio Senior Member Join Date: May 2011 Location: Elyria, Ohio Posts: 755	Rear Main Question ?? We're putting together the best parts of two engines (one a '29 and one a '31) to make one good one. When we tried to bolt on the rear main, the bolts were too long. Finally found in the Les Andrews book (page 137) that two different rear main caps were used. On one the boss was 9/16" tall and the other was 1-1/8" tall. The bolts were 3-5/8" and 4-3/16" respectively. Why the difference, and when did the change take place? Are they interchangeable except for this difference? Marty

05-22-2019, 06:19 AM	#2
Kurt in NJ Senior Member Join Date: May 2010 Location: on the Littlefield Posts: 6,156	Re: Rear Main Question ?? The thinner one is a forged steel cap, thicker one cast iron, interchangeable with correct bolts The forged cap cost more to make. I think the change happened in 1929, would have to look in service bulletins to get exact time

05-22-2019, 05:56 PM	#3
marty in Ohio Senior Member Join Date: May 2011 Location: Elyria, Ohio Posts: 755	Re: Rear Main Question ?? Thanks Kurt. Been playing with this car for over 25 years and I never knew there was a difference. Marty

05-23-2019, 10:49 AM	#4
Bob Bidonde Senior Member Join Date: May 2010 Location: Long Island, NY Posts: 3,463	Re: Rear Main Question ?? The 1931 cylinder block has improvements over the 1929 block. The forged bearing cap is superior to the cast bearing cap in durability (fatigue life). __________________ Bob Bidonde

05-26-2019, 10:50 PM	#5
Dan McEachern Senior Member Join Date: Aug 2010 Location: SF Bay Area Posts: 193	Re: Rear Main Question ?? I like the steel cap because I can tin it rather than use just anchor holes to retain the babbit. I think it makes for a better babbit job.

05-27-2019, 11:34 AM	#6
Railcarmover BANNED Join Date: Apr 2017 Location: Sacramento Posts: 1,262	Re: Rear Main Question ?? Sponsored Links (Register now to hide all advertisements) Are your pouring bearings as part of your services Dan?