Hugeloading856

1. 235 Chevrolet Engine For Sale
2. What Year Is My 235 Chevy Engine

Home: Tim's Trucks ||1954 Documents

Engine Casting Codes & Serial Numbers
1954-1963 Chevrolet 235/261 inline 6 cylinder

(NOTE: these photos are from a 1960 261 engine; however, 1954-63 235 & 261 codes should be in the locations shown below)

Engine Casting Codes & Serial Numbers 1954-1963 Chevrolet 235/261 inline 6 cylinder (NOTE: these photos are from a 1960 261 engine; however, 1954-63 235 &. I recently bought a 1954 3600 Chevrolet Truck. The engine had been replaced with another 235 problem was previous owner did not know the year or mileage. Fortunately the engine runs well and does not smoke. The odometer shows very low mileage, 674 miles. When I looked for engine serial numbers there were none, even under the paint.

PHOTO 1: block casting code
3769717

between and below the distributor hole (left-top) and road-draft-tube hole (right-top)

PHOTO 2: block date-casting code
I 29 9
letter = month; number = day; number = year
September, 29 1959
(CON 4 is to the left of the date code)

lower left on the distributor side of the block
(note the 'captain's bars' - all USA 261 blocks and 1953 passenger car Powerglide-equipped 235 blocks have these bars )

PHOTO 3: engine serial number
F0930LB

on the ledge to the left of where the distributor enters the block

PHOTO 4: ??? - B 61 - 848 850 - ???

How are these decoded ??? All heads I have seen start with the 'B'

on the head, between spark plus 2 & 3

PHOTO 5: head codes on manifolds' side - see next two photos, below

head casting-code on left & head date-casting code in front of valve springs on the right

PHOTO 6: head casting code
3836850
(CON 12 is another casting under the valve cover and GM 5 is under the head casting coode)

top, middle of the manifolds' side of the head

PHOTO 7: head date-casting code
L 17 9
letter = month; number = day; number = year
December 17, 1959

check out this web page by Bob Adler

on the top of the head, under the valve cover, between the 4th and 5th cylinders' valves

235 Chevrolet Engine For Sale

Home: Tim's Trucks ||1954 Documents

Date Codes
Date codes on engines and their parts can help verify if an engine is original to a car. This is especially helpful on cars that do not have a VIN stamped on their engines. Starting in 1962, most high performance engines would be stamped with the cars VIN but this left out all other powerplants and cars built prior to '62. (it wasn't until 1968 that mandatory VIN stamping on all engines was enacted) When a car's VIN matches the VIN stamped on the block, it shows that it's the original engine to the car. (providing it wasn't 'restamped' by a forger) This is commonly known as a 'numbers matching' car.
In order to be 'correct', these date codes have to 'pre-date' the cars build date which can be found on the cowl tag by a few days to weeks as the powerplants (as well as transmissions and rear axles assemblies) were prepared ahead of time. (time will vary) By finding a date code that is passed the cars build date ensures that the engine or part is not original to the car.
Date codes can be found cast into most major engine parts such as; block, heads, intake manifolds*, exhaust manifolds, crankshaft, water pump and flywheels. Some parts will have date codes stamped into them such as the engine block assembly date and VIN code, rear axle, alternator, generator, distributor and starter. The transmission and rear axle assembly will also have date codes.
The engine block date code can be found cast into the rear of the block as shown in the pic above. (a bright light and cleaning this area with brake cleaner helps if engine is still in car) One side will have the block casting code and the other will have a date code. This is the date for when the block was casted. There is a date stamped on the front of the block for when it was assembled. For the heads casting date, you'll need to remove the valve cover and look between the stud bosses. (the casting number can also be found here)
*-special note, high performance aluminum intakes may have date codes located under the oil splash heat shield
A few examples of date codes:

A10 - January 1st, 1960 E13 - May 1st, 1963 L224 - December 22nd, 1964 J305 - October, 30th, 1965 A2962 - January, 29th, 1962

See picture above for a sample of this type of date code.
Use this chart to decode them:

Month A-January B-February C-March D-April E-May F-June G-July H-August I-September J-October K-November L-December

Day 1-31

Year 0-1960 1-1961 2-1962 3-1963 4-1964 5-1965 Or: (as shown above) 60-1960 61-1961 62-1962 63-1963 64-1964 65-1965

Occasionally, a Julian Date was used instead of the above. This type consists of only 3 digits. Leap year must be taken into account with this date format to be accurate. For the 1958-65 cars that we are dealing with, only 1960 and 1964 had leap year or an extra day (Feb 29th). Use the appropriate charts below for your year.
A few examples:

What Year Is My 235 Chevy Engine

A few examples of Julian Date codes below:

070 - March 11th for a non leap year or March 10th with leap year 315 - November 11th for a non leap year or November 10th with leap year 361 - December 26th for a non leap year or December 27th with leap year

Click here to view a sample of a Julian Date Code
Use these charts to decode them:

Julian Date Calender-Non Leap years (1958-1959-1961-1962-1963-1965)
Day	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec	Day
1	1	32	60	91	121	152	182	213	244	274	305	335	1
2	2	33	61	92	122	153	183	214	245	275	306	336	2
3	3	34	62	93	123	154	184	215	246	276	307	337	3
4	4	35	63	94	124	155	185	216	247	277	308	338	4
5	5	36	64	95	125	156	186	217	248	278	309	339	5
6	6	37	65	96	126	157	187	218	249	279	310	340	6
7	7	38	66	97	127	158	188	219	250	280	311	341	7
8	8	39	67	98	128	159	189	220	251	281	312	342	8
9	9	40	68	99	129	160	190	221	252	282	313	343	9
10	10	41	69	100	130	161	191	222	253	283	314	344	10
11	11	42	70	101	131	162	192	223	254	284	315	345	11
12	12	43	71	102	132	163	193	224	255	285	316	346	12
13	13	44	72	103	133	164	194	225	256	286	317	347	13
14	14	45	73	104	134	165	195	226	257	287	318	348	14
15	15	46	74	105	135	166	196	227	258	288	319	349	15
16	16	47	75	106	136	167	197	228	259	289	320	350	16
17	17	48	76	107	137	168	198	229	260	290	321	351	17
18	18	49	77	108	138	169	199	230	261	291	322	352	18
19	19	50	78	109	139	170	200	231	262	292	323	353	19
20	20	51	79	110	140	171	201	232	263	293	324	354	20
21	21	52	80	111	141	172	202	233	264	294	235	255	21
22	22	53	81	112	142	173	203	234	265	295	326	356	22
23	23	54	82	113	143	174	204	235	266	296	327	357	23
24	24	55	83	114	144	175	205	236	267	297	328	358	24
25	25	56	84	115	145	176	206	237	268	298	329	359	25
26	26	57	85	116	146	177	207	238	269	299	330	360	26
27	27	58	86	117	147	178	208	239	270	300	331	361	27
28	28	59	87	118	148	179	209	240	271	301	332	362	28
29	29	88	119	149	180	210	241	272	302	333	363	29
30	30	89	120	150	181	211	242	273	303	334	364	30
31	31	90	151	212	243	304	365	31

Julian Date Calender-with Leap Years (1960 & 1964)
Day	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec	Day
1	1	32	61	92	122	153	183	214	245	275	306	336	1
2	2	33	62	93	123	154	184	215	246	276	307	337	2
3	3	34	63	94	124	155	185	216	247	277	308	338	3
4	4	35	64	95	125	156	186	217	248	278	309	339	4
5	5	36	65	96	126	157	187	218	249	279	310	340	5
6	6	37	66	97	127	158	188	219	250	280	311	341	6
7	7	38	67	98	128	159	189	220	251	281	312	342	7
8	8	39	68	99	129	160	190	221	252	282	313	343	8
9	9	40	69	100	130	161	191	222	253	283	314	344	9
10	10	41	70	101	131	162	192	223	254	284	315	345	10
11	11	42	71	102	132	163	193	224	255	285	316	346	11
12	12	43	72	103	133	164	194	225	256	286	317	347	12
13	13	44	73	104	134	165	195	226	257	287	318	348	13
14	14	45	74	105	135	166	196	227	258	288	319	349	14
15	15	46	75	106	136	167	197	228	259	289	320	350	15
16	16	47	76	107	137	168	198	229	260	290	321	351	16
17	17	48	77	108	138	169	199	230	261	291	322	352	17
18	18	49	78	109	139	170	200	231	262	292	323	353	18
19	19	50	79	110	140	171	201	232	263	293	324	354	19
20	20	51	80	111	141	172	202	233	264	294	325	355	20
21	21	52	81	112	142	173	203	234	265	295	326	356	21
22	22	53	82	113	143	174	204	235	266	296	327	357	22
23	23	54	83	114	144	175	205	236	267	297	328	358	23
24	24	55	84	115	145	176	206	237	268	298	329	359	24
25	25	56	85	116	146	177	207	238	269	299	330	360	25
26	26	57	86	117	147	178	208	239	270	300	331	361	26
27	27	58	87	118	148	179	209	240	271	301	332	362	27
28	28	59	88	119	149	180	210	241	272	302	333	363	28
29	29	60	89	120	150	181	211	242	273	303	334	364	29
30	30	90	121	151	182	212	243	274	304	335	365	30
31	31	91	152	213	244	305	366	31