Engine and Bearing ID.. need help

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Nov 29, 2010 | 12:06 PM

sitdog84

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5th Wheeling

Joined: Nov 2010

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Engine and Bearing ID.. need help

I just tore apart my 300 out of a 70 F100. The engine id tag is rivited to the block with a number of H31316. Does that relate to a 70's engine ?? Also pulled out the main, rod and cam bearings, here are the numbers:
main cap- C5TE-6A338-S .010
main in block D42E-6333-DB 0.25
not sure what size to get since 2 different sizes??
rod- C8TE-6211D .010
Cam D5TE-6262BA

thanks for any and all help.

Ken

Nov 29, 2010 | 06:22 PM

desperado_18_2000

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Joined: Jan 2001

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From: S. Mississippi

I would say that you have an amalgamation of an engine there. None of it is particularly wrong, but if you found a date code casting of D5, then it is from a 75 model engine as that as when that part was cast.

As far as the tag riveted to the block, I haven't a clue.

Nov 29, 2010 | 06:43 PM

Rogue_Wulff

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From: Lost

Tag riveted to the block typically indicates the motor was rebuilt by some big outfit. The number means little to most anyone else, just to the engine builder.
As for the bearing sizes, .010 is ten thousandths of an inch, and .25 is 25 hundredths of a MM. Ironically, they're the same thickness. That whole 25.4MM=1" thing......
Looks like you will need .010 oversize rod and main bearings, assuming the crank is still within specs.
Cam bearings aren't offered in oversize, since the cam is disposable. By the time the bearing journals are worn, the lobes are usually well beyond use. However, there are differences in the sizes of the cam bearings (on most engines), which is why they are typically numbered by location in the block.

Nov 29, 2010 | 07:24 PM

sitdog84

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5th Wheeling

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Thanks for all the help. After the .010 and 0.25 is US. Does that mean undersize??

Nov 29, 2010 | 09:26 PM

Rogue_Wulff

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From: Lost

The bearings are oversize, as the crank has been ground .010. Hope that helps clear up the confusion.

Apr 20, 2020 | 11:15 PM

1978F100Custom

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Joined: Jan 2020

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Help

I know this is an old thread, but I'm hoping to find some answers... I am rebuilding a 1978 F100 300 inline six. The truck was purchased on March 14, 1978 by my Dad. The build date on the door says 3/78. My Dad kept meticulous records, and no one recalls this truck being worked on to this level.

I have completely disassembled the engine. The markings on the bearings are as follows:

Main bearings (cap)
D.A.B
1-78-G PC
C5TE6A338-S
010- U.S.

Rod Bearings
D.A.B
12-77. R. PC
C8TE-6211-A-B

Fm
Ford Logo
D42E-6A339-DB
0.25 USw2
11-77

The main bearings range in dates. 10/77; 11/77; 12/77. I do believe the .25 and .10 are the same undersize. (.25 being metric).

Any insight on how this could have occurred? I am not ruling out that something occurred early on and warranty work was done. I thought it was odd to see another vehicle with the same bearings....