After a long hunt, I finally found me a 261 about 70 miles from home the other day. Yesterday did some dirt rubbing and cleaning and here is what it is: Block number 3769717, Casting date C 1 2, Engine serial F0313LB Any info would be appreciated. I know it was a big truck because it had the big vacuum port on the side of the intake for the 2 speed rear end vacuum source. A couple head scratchers is it has a oil filter canister that was hooked up just like my 235 in the bypass mode. The big tapped oil ports had factory plugs on them and the dowel is remained flush with the block, I believe in bypass mode. So didnt all these engines from the factory have the dowel punched in for full oil filtration? Why was this engine in the bypass mode? Engine spins easy and is stock bore.
Another interesting note is this odd looking thermostat I found in the housing, looks like it says 160 on it, anyone have anything to say just what is the purpose of this? The water pump looked like a stock automobile one.
Carburetor looks like a bigger venturi and correct for the 261.
Head was casting 3836850 , C16 9. Exhaust valve on number 5 was stuck and the pushrod was bent.
Any input and comments will be appreciated, was thinking of getting it ready to go into my 53 3100
Steve
Last edited by sstock; 04/04/20192:16 PM.
1953 Chevrolet 3100 261 cu inch, sm420, 3.55 rear, torque tube still,omaha orange, still 6 volt, RPO green glass, side carrier spare, all done In the DITY Gallery Video of the 261 running
1964 GMC 1000 305 Big Block V6, sm420, the next cab off restoration
