Casting numbers
 

I just checked my block casting number and its 3837004 I looked it up and they are 56 numbers one one site and 55-57 numbers on another. My truck is a 59. Is there any difference I should know about between my 59 and the earlier numbers? Will the parts on both motors interchange or were there changes from year to year?

Re: Casting numbers
 

3837004 was used from 55-57, 235ci.
Shouldn't be any issue with using this in your '59.
Post the numbers that are stamped just behind the distributor and that will tell exactly what it was installed in originally.

Re: Casting numbers
 

MJN nailed it.

Check the serial number on the block This list goes to 57 for 235 engines http://chevy.oldcarmanualproject.com/models/engine.htm

If you scroll down to 37/83 it shows how to figure out the engine serial number on a 59.

The 59 block should have an F or T, 3 digit number denoting month and day and a letter denoting the model it was built for. This is the engine serial number page.

Re: Casting numbers
 

F822HE it looks like but its pretty dirty

Re: Casting numbers
 

Your original assumption seems to be correct. 57 engine built in Flint Michigan on August 22 and a regular production engine.

One has to believe that that was what a former owner found when they went looking for an engine to replace the one that was in it.