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| | | | Joined: May 2015 Posts: 19 New Guy | | New Guy Joined: May 2015 Posts: 19 | I'm trying to figure out which engine I have in my 1949 3600 and the normal websites do not seem to list it. The previous owner says it is a 235. The flat plate shows a stamped number: 0208342F54Y and the block show casting: CON4 A124 12 GM
It has a valve cover held down by two studs running up through the center of it. Shouldn't this make it a 216 or early 235?
I really appreciate any help you can give me.
George
1949 3600 with a 235 and T5
| | | | | Joined: May 2006 Posts: 8,351 'Bolter | | 'Bolter Joined: May 2006 Posts: 8,351 | According to the serial number, it's a 1954 235 built at Flint, and originally was in a '54 Passenger car with RPO 313 Powerglide Transmission. The other numbers you posted indicate it was cast on Conveyor 4, and was cast on January 12, 1954.
As far as the cover goes, I have heard of early '54s using the older style cover, but since putting the older cover on the newer engine only requires installing the proper bolts with the studs from the earlier engine, that could be the case as well.
Bill Burmeister
| | | | | Joined: Sep 2001 Posts: 29,269 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,269 | What is the head casting code and the head date casting code? You could have a 1953 head, or you could have a 54 head that has been "converted" to use the older two-bolt valve cover (as Bill posted above). Are there two screw holes in the head on each side of the valve cover (I do not recall if those 4 holes show on a 54-63 head that is converted to using the older 2-bolt valve cover? | | | | | Joined: May 2015 Posts: 19 New Guy | | New Guy Joined: May 2015 Posts: 19 | Wow, thanks for the quick responses! From the link it sounds like my head is from a 261. Does that make sense? Also from Wikipedia it sounds like a 1954 passenger car with the automatic would have hydraulic lifters and be fully pressurized - is that correct? If so I'll take it!
On the carb side it is #3836850 GM1. On the distributor side it says B46 848 850. There are three screw (bolt) holes on the distributor side of the head.
George
Last edited by George Smathers; 08/28/2016 1:09 AM.
1949 3600 with a 235 and T5
| | | | | Joined: Sep 2001 Posts: 29,269 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,269 | George,
3836850 is a code for a 261 head over many years. What is the head date casting code (under the valve cover - check the link I gave in my earlier post).
That head could have been put on your 235 at some time over the years.
Are there screw holes on the top of the head, outside the edge of the valve cover (2 holes on each side of the valve cover, for the original valve cover)?
| | | | | Joined: May 2015 Posts: 19 New Guy | | New Guy Joined: May 2015 Posts: 19 | There are no screw holes on top of the head outside the edge of the valve cover. I think that head code makes it a 1954-55.
Last edited by George Smathers; 08/28/2016 2:00 AM.
1949 3600 with a 235 and T5
| | | | | Joined: Sep 2001 Posts: 29,269 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,269 | Yes, it is a high pressure 235 block.
Yes, all Powerglide-equipped car 235s had hydraulic lifters.
I think that 261 head code was used from 1954-1963. | | | | | Joined: May 2015 Posts: 19 New Guy | | New Guy Joined: May 2015 Posts: 19 |
1949 3600 with a 235 and T5
| | | | | Joined: Jun 2011 Posts: 5,096 Crusing in the Passing Lane | | Crusing in the Passing Lane Joined: Jun 2011 Posts: 5,096 | 261 heads have steam holes.
Ed
'37 GMC T-18 w/ DD 4-53T, RTO-610, 6231 aux., '95 GMC running gear, full disc brakes, power steering, 22.5 wheels and tires.
'47 GMC 1 ton w/ 302, NP-540, 4wd, full width Blazer front axle.
'54 GMC 630 w/ 503 gasser, 5 speed, ex fire truck, shortened WB 4', install 8' bed.
'55 GMC 370 w/270, 420 4 speed, grain, dump bed truck from ND. Works OK.
| | | | | Joined: Sep 2001 Posts: 29,269 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,269 | Yes, 261 heads have 6 extra coolant passages to match up with the coolant passages in a 261 block; however, it should cause no harm if they are blocked by the 235 head gasket and 235 engine block. | | | | | Joined: Mar 2010 Posts: 10,272 Renaissance Man | | Renaissance Man Joined: Mar 2010 Posts: 10,272 | If there are not four 1/4" bolt holes at the top of the head where it meets the valve cover (they may be covered by the older style 2-acorn nut valve cover), how can it be a '54 head of any description? The last year for the 2-acorn nut head (no 1/4" holes) was 1953.
Carl
1952 5-window - return to "as built" condition | 1950 3100 with a 235 and a T-5 transmission
| | | | | Joined: Sep 2001 Posts: 29,269 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,269 | You might have to take off the valve cover to find the 4-holes for the newer valve cover (If you do not have a 1953 head).
If/when you take off the valve cover, you can date the head.
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