318 engine identification (what year?)

MoPar~Man

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My 1967 Monaco (Canadian car) came with a 318 (which I understand was not offered in the US, it would have been a 383). This was my dad's car that I restored during the 1985 - 1989 time frame. I believe the original engine was a different block, possibly what was used in US cars in 1966 and earlier but the left-over blocks were used in Canadian cars in 1967. Was this the "Y" block, replaced with the "LA" block? I believe these older engines were about 100 lbs heavier.

Anyways, during that restoration I took the engine out of the car and bought a remanufactured engine from a local Chrysler dealership. The original engine went to the dealership as a core exchange.

Bottom line - I don't exactly know what year engine I got. It could be anything from the 1970's up to 1987-ish (but likely something from the 80's). What ever it is, it bolted up to the 727 transmission just fine, was mounted in the car just fine, and I drove if for maybe 5k miles before putting the car in storage. I'm working on it now, getting it ready to fire up the engine, and I'm browsing through RockAuto looking at gaskets and seals and I'm wondering if I need to be looking at a more year-appropriate car for parts for this engine. Or maybe I don't? I don't know how similar the 318 would be across that time span. I do remember I had to obtain some parts from probably a junk yard (exhaust manifolds, maybe oil pan, valve covers, probably intake manifold). So if there are any markings on the block or heads that might tell me what year roughly the block would date to, I guess that's what I'm looking for.
 
I don’t know small blocks but I’m sure there’s a casting date on one side or the other of the block.
 
'67 Canadian produced 318's were still "poly" engines.( ie the big one) Poly was replaced by the LA series engines in US produced cars starting in '67 and in Canadian produced cars in '68. Both are considered by Mopar to be small block engines. Quick ID for the Poly engine is that it has two bolt valve covers. The transmission that is correct for a 318 will bolt up to either engine. As noted, there is a casting date on the side of the engine just below the head, you might have to pull the exhaust manifold to get a good look at the date. The LA series engines usually have a small machined pad on the top front of the block just forward of the head (Passenger side). This pad will be stamped with a letter and the displacement: A='65. B-'66, C='67 etc. A '67 318 will have the code C 318 stamped on the pad.

Dave
 
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My 1967 Monaco (Canadian car) came with a 318 (which I understand was not offered in the US, it would have been a 383). This was my dad's car that I restored during the 1985 - 1989 time frame. I believe the original engine was a different block, possibly what was used in US cars in 1966 and earlier but the left-over blocks were used in Canadian cars in 1967. Was this the "Y" block, replaced with the "LA" block? I believe these older engines were about 100 lbs heavier.

Anyways, during that restoration I took the engine out of the car and bought a remanufactured engine from a local Chrysler dealership. The original engine went to the dealership as a core exchange.

Bottom line - I don't exactly know what year engine I got. It could be anything from the 1970's up to 1987-ish (but likely something from the 80's). What ever it is, it bolted up to the 727 transmission just fine, was mounted in the car just fine, and I drove if for maybe 5k miles before putting the car in storage. I'm working on it now, getting it ready to fire up the engine, and I'm browsing through RockAuto looking at gaskets and seals and I'm wondering if I need to be looking at a more year-appropriate car for parts for this engine. Or maybe I don't? I don't know how similar the 318 would be across that time span. I do remember I had to obtain some parts from probably a junk yard (exhaust manifolds, maybe oil pan, valve covers, probably intake manifold). So if there are any markings on the block or heads that might tell me what year roughly the block would date to, I guess that's what I'm looking for.
If you replaced your poly 318 with an LA 318, 1970-1987 gaskets and seals should be pretty much the same.
1969 and earlier LA had different oil pan seals.

As far as casting date, I would avoid pulling the exhaust manifold. Some of the studs are wet and if one comes out of the head, you have a big antifreeze mess. 318 LA blocks did not change 1970-1987, then came 1988 roller lifter engines.

Your casting date should be on the right side (pass side) of block. It's above the time circle shown. Day Night arrow also visible. My 1970 318 was cast at 7:30pm at night.
rs.jpg

Left side has block casting # and CID if you pull down the starter. Again not much help if ordering basic parts for a stock 318.
ls.jpg
 
A reman engine needing "gaskets and seals" after only 5K road miles? If the engine was a Chrysler Reman engine, everything on it should be OEM-spec or similar, I suspect. What you CAN do is to put a wrench/socket on the bolts and see if they might need to be snugged-up a bit. NOT tightened as such, just snugged-up, for good measure.

Poly 318 engines look a bit different than LA-318 engines. NO mistaking one for the other. Especially the valve cover lower edge . . . "angular offsets" on the Poly and smooth on the LA, for example.

As for maintenance items, just match what's in there now. Still, why are they needing replacing with only 5K road miles. Spark plugs can be removed, checked, gap checked/adjusted, and reiinstalled, for example. Ignition points could become tarnished and might need to be replaced, though.

Change the motor oil, a new oil filter, fresh coolant, trans fluid/filter change, etc. Might need a new battery, too?

Just some thoughts,
CBODY67
 
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