Jag Mark IV 1948 - engine number?

Can I find out the original engine number of Jaguar 3½ DHC LHD 1948, chassis 637076 somewhere outside of Jaguar Heritage.

Well it’s not here: http://saloon.collectordata.com/cars/detail/?car=637076


Thx for trying


What’s the problem with JHT?

iIRC it costs £40 GBP to get a certificate from there. Although, because of some problems in the past, they might not give all numbers just like that.

Ferrari or Maserati Classiche would charge you thousands for any paperwork and most likely require you to take the car there as well.

I have used JHT’s services more than ten times and IMHO always got great service and good value for money.


Ps. Do you have the brass plate on the scuttle with the numbers?

Yes, JDHT has to protect themselves from assisting fraudulent matching numbers and stolen cars, so you have to show proof of ownership, give them all the numbers, and they will tell you whether it is the original numbers.


Exactly. With my MKV and unrestored V12 E-type I sent them also photos of the chassis number, body number and gearbox number as found on the car.

On my MKV this was important as the US title (CO) was with engine number and the car has another (older) engine. Also the body tag was missing, but fortunately the body number (1354) could be found on the back of many wooden parts if the body, incl. the instrument panel.

I have advised many people to first take photos if all the numbers on the car and send them to JHT together with proof of ownership. Never had any trouble that way.


Thank you.
You’re right, I have also used JHT several times before and everything was fine. I am also in touch with them now. No complaints about their site. The problem is that the car I bought has no plate and the engine number is illegible. I will probably accept the certificat without an engine number. I have chassis numbers 637076 and body number C1105. It must be enough.

Can you post a picture of it? A LHD Mark IV engine number should begin with the letters SL and usually 4 numerals.

See attached. JHT has got all the photos.

Here is a copy of the normal numbers

Well, poor factory stampings and mistakes are not unknown, as this Mark V engine shows, the last numeral is a 3 stamped over a 2.

Looking at cars near your chassis number, 637076,

if you believe that it is the original engine to the car, which would have the remote oil filter setup mounted on the left rear engine support arm,
and if we take the 019 as legitimate, the only thing that would make sense would be SL3019.
Does that number before the 0 look like the bottom half of a 3?

Not all that helpful without being EXACT, but based on other known DHC Chassis/Body Numbers your Engine Number as a guide will be approximately SL2850 > SL2900 assuming nothing untoward, as Engine Numbers were never in strict sequence normally, let alone with any Engine quality control issues…

@Rob_Reilly quote=“Rob_Reilly, post:11, topic:400584”]
f you believe that it is the original engine to the car
No, not anymore.
Based on current discussions with JHT, I believe this is engine number T9019.
Do you have charts like this for Mark V?

You can browse Mark Vs here.

Thanks. No results when I type T9019.


That would be a valid engine number for an early 1950 MKV.

Too bad you didn’t get this 12-18 months ago when my engine was in bits and pieces. I have a 3 1/2 Litre LHD MKIV engine from 1948 in my July 1950 MKV DHC that originally had engine Z2453.

We could have swapped engines then. Now I have invested hundreds if hours, €3000,- euros in machining and resleeving and thousands in parts and running in the engine. :slight_smile:


1 Like

I’m not sure of my facts regarding the change date but I think the MkIV has this type of crankshaft damper.


Whereas the MkV has this type.


So it may be easy to determine where your engine came from.


Thanks @Peter_Scott Peter I will investigate it.


Exactly, but the only part needed to change it is the pulley. I swapped the MKIV pulley (much rarer, although not complicated to make out of alloy if you have a lathe) to a MKV pulley with Ed Nantes. You just turn the damper 180 degrees. And the belt line is the reason they did it, thus the MKV has different brackets for the dynamo and a 1” casting between the water pump and engine block.

I still have the MKIV dynamo brackets, I just used longer bolts and normal Jaguar 1” spacers to align the dynamo / generator.


The reasonable conclusion is that it was in a car that has not been recorded on the site, either gone or not surfaced anyway.

Along with the pulley and damper reversal, the Mark IV to Mark V changes brought the generator more forward, and I think maybe a little upward, in order to clear the steering column on LHD cars. And all Mark Vs had the air cleaner on top. They also put the oil filter back on the side of the block, where LHD Mark IV needed the remote filter with hoses to clear its steering column. LHD clutch linkage was also much improved on Mark V.