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Serial number question

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N

Nader

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I can't find a serial number on the engine. There's no tag on the right side, or anywhere. But on the firewall, it looks like an additional tag was wedged under the chassis ID tag. Is that supposed to be there? It's possible that the engine may be a transplant. Also, someone here pointed out in my other thread that the center shift transmission on this car is a retrofit. Car is a '59 BN4. Can anyone with access to reference books tell me what these numbers mean, and what that extra serial number is? When I Google it, I get a chassis number for an ex-race car driven by Jack Breskovich in the mid '50s-'60s. Thanks.
 

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That extra plate is the 'allocation number' which was used only on the later BN4s. Page 75 of the restoration guide has some details about it. Below is a copy taken from Google Books

What is really curious is that the resto guide on page 136 lists the last BN4 produced as BN4/74421 and yours at BN4/74913 is therefore a little unusual. Given that the early 3000s were sent out with 100/6 badges I'd say there was a fair bit of crossover between the new and old models, particularly if they had stock of earlier engines to use up.

Post up some pics of the engine/head casting numbers, somebody'll be able to identify if it is a 2.6 or 3000.

Andy.
 
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Nader, remove the two screws holding the chassis number on (the rectangular one) and post a picture of the other plate under it, please.
 
Here's the plate under the plate, and the head casting. What is this engine?
 

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AEC 721 is the earliest 12 port head casting AFAIK so there is a reasonable chance that is the original engine. You can apply for a Heritage Certificate which will give all the vehicle details.

Andy.
 
Nader,

The 2.6L engines have AEC 335 cast into the side of the block under the carbs.


Duane
'58 BN6
 
According to Clausager the number of the last BN4 produced was 77766. Some early 3000s went out with 100-Six badges on them and BMC produces various manuals referring to the '100-Six BT7 & BN7'. Although they were badged 100-Six they did have the 3000 engine and were referred to as BN7s & BN7s. This car is one of the last BN4s and would have had a 2640cc engine.
 
DerekJ said:
According to Clausager the number of the last BN4 produced was 77766. Some early 3000s went out with 100-Six badges on them and BMC produces various manuals referring to the '100-Six BT7 & BN7'. Although they were badged 100-Six they did have the 3000 engine and were referred to as BN7s & BN7s. This car is one of the last BN4s and would have had a 2640cc engine.
Click to expand...
And just so you know they also did it the other way, a SE Michigan Healey restorer, Tim Kozlowski did a one-owner, all original BN7 (badged as a 3000) that turned out to have a 2.6 ltr engine. I rebuilt the sideshift xmsn for that car while the numbers-matching original engine was being machined at a then local Toledo shop, and was consulted on the what to do (keep the 2.6 or substitute a 2.9), and if I needed a set of the already purchased 3000 +/os pistons...

Ultimately, the car was restored as original, with the 2.6 engine, even though the owner had initially wanted a little more out of the 2.9!
 
57_BN4 said:
What is really curious is that the resto guide on page 136 lists the last BN4 produced as BN4/74421 and yours at BN4/74913 is therefore a little unusual. Given that the early 3000s were sent out with 100/6 badges I'd say there was a fair bit of crossover between the new and old models, particularly if they had stock of earlier engines to use up.
Andy.
Click to expand...

The "last one" produced depends on how you define it. The cars were not necessarily built in chassis number order. For example, the last BJ8 that completed production was chassis 43000 (built 23 Nov 67 - 11 Jan 68), but the highest chassis number built during series production was 43025 (built 1 - 16 Nov 67).
 
Thanks for the replies.

So what's with the center shift transmission on this example? Not necessarily the mark of a 3L? BTW, the head on the car is a replacement for the original which cracked.
 
On the possibility that the center shift transmission originated in a BJ8, I would be interested in knowing the serial number of your gearbox. I can find out which car it was original to.
The centershift gearbox serial number is stamped on the passenger's side of the gearbox case, on a raised "boss" in the center of one of the "waffles". If it came from a BJ8, it probably has an "M" stamped on the boss above the number.
 
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