L18 Serial number questions

[Eomund]

Just to give a vehicle background, this is a '72 521 pickup that I had purchased thinking it was the original motor. I was wrong.

 

Today's been an interesting day. I started by researching why I had two oil dipstick tubes to find out that it's likely that my motor is possibly imported, haven't 100% confirmed this as most info I've found doesn't seem conclusive.

 

What I have learned is I have an L18 with a A87 head. What's not making sense to me is the serial numbers. I have several books that describe the numbers but they do not match anything I'm seeing on the motor.

 

I don't have and pictures but it reads the following:

L18 281218 W

 

Each one is on it's own plate. First, no prefix letters, unless the L18 counts as the prefix, which matches nothing I've read. Also I haven't found any information on the lone W at the end. I've checked re-checked triple checked and quadrupal checked the numbers and they're accurate.

 

What I'm thinking is this is possibly a JDM motor, one of the ones imported in the early 80's. All my books are american and only cover the US and I'm hoping it's this, 'cause that would mean I have the peanut head which would rock.

 

Any info on this would be epic.

 

-Eomund-

[DanielC]

I have a JDM L-18 in one of my 521 trucks. It was fuel injection, peanut head, and also has a fully counterweighted 6 bolt flywheel .

Engine number L-18 797327.

[flatcat19]

Imported crate motor.

That's all.

 

Good chance though that the A87 head on there is a peanut.

Take it apart to find out.

[datsunaholic]

W on the end of the casting always denotes a very late, 1979 or later engine. I've seen a few L20Bs with the W, and they actually are a NAPS-Z casting but have had the L-series machining doen on them. Starting in 1979-ish, all 4-cyl L-series blocks came out of the NAPS-Z casting line. You'll notice, under the manifolds, there's a boss where the NAPS-Z serial number plate would be. It's not machined, though, and won't have anything there. But the place is. I've seen L16 blocks with the same setup (including the 2 dipsticks). 2 dipsticks is the main ID characteristic of a "crate" engine, as late L-series cars had a front-sump pan so far forward the rear dipstick was unusable (cars like the A10 and possibly the 710).

 

You likely have a peanut head, BUT it could have been swapped on. It may or may not be JDM, as it could have been a dealer replacement "crate" engine. However, every Crate engine I've seen (and all were L16 and L18s) did have peanut heads, and the "W" block L20Bs I've seen did as well.

[ggzilla]

You cannot tell which head it has by the engine block numbers. Anything could have happened over the last 30+ years.

[Eomund]

Thanks for the quick reply guys. Any indication what the W means?

[Eomund]

n ever mind the w question. You replied to quick :P

[flatcat19]

W means WORD!

 

Translation...better.

 

 

 

 

 

 

 

:rofl:

[ggzilla]

So what does the W mean? I read the above, but still didn't get it

 

W on the end of the casting always denotes a very late, 1979 or later engine.

Ah, Datsaholic has the answer once again. Thanks!

[flatcat19]

When a NISSAN motor carries the W casting is is of a stronger cast.

 

Example:

300zx's VG's show this more prominently.

84-86 is the weaker of that series of block.

87-89 have different webbing on the block to increase the strength.

 

I have seen the W on L's, Z's, VG's, and VQ's.

[Rays74]

Interesting topic, thanks for the info 'Holic :) I bought the L16 ( that's in Ol Yeller's '73) out of an importer's shop in Long Beach approx 12-13yrs ago and always wondered why it had twin dipstick receiver's .....lol. It had those weird combined intake/exhaust manifolds that have no water galley's in the intake or head. His block also has the blank stamping pads under the manifolds ;)

Next time I'm over there I'll look for that "W" in the serial#.

 

--Ray

[ggzilla]

W is also the code for the Nissan Kyushu plant.