The engine serial number is different to the vehicle serial number. I believe that your engine is a 1953 passenger car engine. (Tim Lederman is the engine number expert. He may give better information.)
L = 1953 Model Year
A = Passenger Car
S = Engine built at Tonawanda, NY engine plant with RPO 313 and RPO 324
525272 (minus 1,001) = the 52,4274th engine built at the plant
RPO 313 = Powerglide
RPO 324 = Hydrolic Steering (power steering)
The 1953 passenger car Powerglide engine was different to 1953 truck engines:
235.5 cu in, instead of 216 cu in in 3100 truck
Full pressure lubrication vs spray oiler in 3100 truck
Hydrolic lifters instead of solid lifters in 3100 truck
Advertised max engine performance:
GBHP = 115 @ 3600 RPM
NBHP = 108 @ 3600 RPM
G Torque = 200 ft lb @ 2000 RPM
N Torque = 196.5 ft lb @ 1000 RPM
I believe that the valve cover was held to the head by two acorn nuts on top. The 1954 valve cover had four slots on top and was held to the head by four screws.
Documentation:
1953 Passenger Car serial numbers
http://chevy.oldcarmanualproject.com/chevyresto/53009.htm1953 Passenger Car RPO
http://chevy.oldcarmanualproject.com/chevyresto/53044.htm1953 Powerglide Automatic Transmission Supplement (blank page), see "next pages"
http://chevy.oldcarmanualproject.com/chevyresto/53045.htmMore engine number on pdf p 12 of 123 of Truck Vehicle Information Kit at GM Heritage Ctr.
http://www.gmheritagecenter.com/doc...hevrolet-Trucks/1953-Chevrolet-Truck.pdfSerial number locations on 1954 trucks:
http://chevy.oldcarmanualproject.com/shop/1954truck/54ctsm000.htmlhttp://chevy.oldcarmanualproject.com/chevyresto/54057.htm- Lonnie