Identification

[Jack]

I was discussing with Jack last night and we came to the conclusion that we should construct a history of pictures of these changes. We also need to explain any anomalies or uncertainties.

I think it needs a table of "Change, From Chassis no X, Date, Photo" which shows each change as it happens. It could be a huge file by the time we are done, but suggest it gets split into body and aesthetic changes like the headlamps, grille, rear light, and then a separate one covering mechanical changes such as the modifcations to the engine or suspension.

Luckily, the changes to the mechanicals are largely done for us here: http://jowett.net/Parts/TechNotes-Part2 ... alData.htm - see item 5, it has the major modifications. I will copy them here, so that we've got the data to hand - it took me a few minutes to find, I think one thing we need is to have a quick links section that has things like Javelin Identification, engine rebuild information, an index of rebuild project threads, and that sort of information thread to avoid duplicate threads trying to find the same topics - and also so everyone can find them.

Notes from Mike Allfrey, if we work from the engine numbers (which originally should have largely matched the chassis no) we can also work out the approx dates, and these can be refined by referring to the Tech Bulletins which had the month and year for each change:

"E = 5 Being the first digit of the decade. ‘A’ = 1, ‘B = 2, ‘C’ = 3 and ‘D’ = 4 (all Javelins will be either D or E)
1 = 1 Being the year in the decade.
P = Passenger car (i.e. Javelin)
C = Third build series. ‘A’ = First series, ‘B’ = Second series.
12778D = The individual vehicle number.

Summary Of Javelin Engineering Changes

Change Description Effective From

Flywheel and clutch assembly balanced as a unit. D8 PA 100
Exhaust manifold flanges increased in diameter. D8 PA 164
Redesigned air silencer. D8 PA 185
Hydraulic tappet fitted with end cover. D8 PA 781
Expansion chamber fitted to exhaust system. D8 PA 997
Carburettors Changed from 30VM4 to 30VM5 (Type ‘M’). D8 PA 1753
Flywheel bolts, diameter increased from 3/8“ to 7/16”. D9 PA 2200
Dynamo changed from C.45 to C.39. D9 PA 2259
Connecting rod bolts, diameter increased from 5/16” to 3/8“. D9 PA 2373
Spring arm trunnion bushes pressed on, retaining nuts deleted. D9 PA 2554
Steering box eccentric bush incorporated. D9 PA 2871
Exhaust system, single rear silencer. D9 PA 3138
12 volt single battery fitted. D9 PA 3696
Copper-lead connecting rod bearings fitted. D9 PA 3794
Fitting of starter solenoid and electrical harness alterations (RHD). D9 PA 4243
Copper-lead front and centre main bearings fitted. D9 PA 4322
Oil bath air filter fitted (export only). D9 PA 4431
Oil bath air filter fitted (all models). D9 PA 5374
Vacrom piston rings fitted (T/C 27). D9 PA 5756
Modified water pump (T/C 26). D9 PA 5857
Front suspension lubrication, revised method (T/C 27). D9PB 5979
Adjustable steering ball joints fitted (RHD). D9 PB 6572
Adjustable steering ball joints fitted (all models). E0 PB 6801
Exhaust system, introduction of detachable tail pipe. E0 PB 7509
Redesigned rear timing case cover. E0 PB 7676
Introduction of detachable exhaust tail pipe. E0 PB 8276
Trico type windshield wiper blades fitted. E0 PB 8276
New type steering link fitted (‘H’ section stamping). E0 PB 8313
Oil cup added to water pump housing. E0 PB 8472
Small end bearing changed from ‘Glacier’ to ‘Clevite’ metal. E0 PB 8737
Introduction of strengthened cylinder liners and ‘barrel ground’ pistons. E0 PB 8825
Hardened crankshaft fitted (RHD). E0 PB 8902
Hardened crankshaft fitted (LHD). E0 PB 8937
Change to screws in air filter assembly. E0 PB 8950
Horn relay fitted to horn wiring circuit. E0 PB 9293
Engine oil filter outer casing strengthened. E0 PB 9423
Main bearing dowel drilled. E0 PB 9540
Engine oil delivery pipe union wired for locking purposes. E0 PB 9860
New type lower fixing arrangement for front shock absorbers. E0 PB 9877
Steel sump tray assembly. E0 PB 9878
Reinforced front engine mountings (vertical stay deleted). E0 PB 10450
Introduction of serrated connecting rod assemblies. E0 PB 10506
Introduction of four wheel hydraulic braking system. E0 PB 10594
Redesigned steering rod ball joints. E0 PB 10789
Change to gear ratios. E0 PC 11270
1951 Javelin model commences from – E0 PC 11326
Solid type tappet fitted (RHD). E0 PC 11907
Solid type tappet fitted (LHD). E0 PC 11940
Adjustable type selector and gear change links (RHD). E0 PC 12340
New ‘clear view’ steering wheel and lengthened steering column. E0 PC 13111
New design oil pump relief valve and spring, pressure now 70 psi. E1 PC 15098
Redesigned front grille (die cast) and bonnet motif. E0 PC 15631
Rubber bonded exhaust system mountings. E0 PC 15432
Increased strength front shock absorbers. E1 PC 16500
Full flow engine oil filter (Tecalemit). E1 PC 16603
Lubrication groove, centre main crankshaft bearing. E1 PC 16744
Sludge release hole, big end bearings. E1 PC 17402
Cylinder head gasket support. E1 PC 17900
Water pump modifications. E1 PC 18140
Gearbox extension bearing washer. E1 PC 18141
Connecting rod bearings, drilled hole in connecting rod half shell deleted. E1 PC 18646
Throttle rod assembly, redesigned clamp bolts (RHD & LHD). E1PC 18550
Engine oil return from release valve into suction pipe (adjustable valve). E1 PC 18985
Camshaft and chainwheel with vernier adjustment. E1 PD 19295
Improved waterproof plug lead covers. E1 PD 19760
Introduction of adjustable gear change stay (RHD & LHD). E1 PD 20135
Revised taper at water pump shaft and fan hub introduced. E2 PD 20379
Deletion of oil sludge drilling in connecting rod cap. E2 PD 20977
Introduction of Lucas DM2 model distributor. E2 PD 21016
Introduction of petrol filter in feed pipe. E2 PD 21147
Rubber bushed front suspension introduced. E2 PD 21868
Updated crankshaft introduced. E3 PE 22873
Engine lubricating oil pump with extended body introduced. E3 PE 23122
‘O’ Ring type cylinder liner seal introduced. E3 PE 23184
Adjustable camshaft end-float introduced. E3 PE 23643"

These go up to E3, so 1953 production, so hopefully is comprehensive. It is certainly a very good start on what we are trying to achieve and easily read and understood.

Jack.

[Forumadmin]

The paper compiled by Bob Jones is here http://jowett.org/jowettnet/dt/tech/jti/jav.pdf or if you want the index it is here http://jowett.org/jowettnet/dt/tech/hb/j2-jti.htm

The Index for the Mike Allrey technical notes is here http://jowett.net/Parts/TechNotes-Part01-Index.htm. Links send you off to the various chapters.

[Robin Fairservice]

Hi Robert,

Well spotted! You are absolutely right that the Jowett Factory engineering change notices refer to ENGINE numbers as defining when changes were introduced, even when those changes refer to bodywork, brakes etc. I hadn't spotted the difference and made the assumption that they were refering to chassis numbers.

I have the original buff log book for NKJ 352 and the numbers quoted there (on 12th October 1950!) state that the chassis number is EO/PB/10866/D and it shows the same number for the engine. I wonder if the engine and chassis were stamped on the production line?

Of course, over time I guess the majority of Javelins will be showing different numbers for the chassis and engine, as us Jowetteers have a habit of swapping engines almost on a yearly basis? I know that DCB 246 has a chassis number of E2/PD/20893 but an engine number of E3/PE/35xxx ( cannot recall the exact number without rushing out to the garage this morning! )

All the best,

David

Where is a Javelin engine number? Certainly not on the identification plate which only shows the body number. My engine nas a block number 10742, but the chassis number is 10010 D, and I have no reason to suspect that this is not the original engine. According to the club's records my car was shipped from England on August 21, 1950 and is a PB. We don't have log books in British Columbia, as in England, but my Registration document just quotes the Model and Chassis numbers.

[Jack]

Where is a Javelin engine number? Certainly not on the identification plate which only shows the body number. My engine nas a block number 10742, but the chassis number is 10010 D, and I have no reason to suspect that this is not the original engine. According to the club's records my car was shipped from England on August 21, 1950 and is a PB. We don't have log books in British Columbia, as in England, but my Registration document just quotes the Model and Chassis numbers.

Hi Robin,

I think we are all looking at the number stamped on the raised plinth on the right hand side of the engine (viewed from the front) which certainly seems to match the chassis number on many very original cars.

Of course this number could be different on those cars where the engine has been swapped for another, and I suppose might give a clue to where the engine came from. But none of the numbers referred to in the documents are in the right format to be anything other than the matching number from the chassis, so perhaps should really say chassis number - I suspect as the technical notes are quite focused on the changes to the engine and gearbox it makes sense to identify them by this number, but of course if we are looking at cars (and what they should be or were as they left the factory) it is easier to work from the chassis number as engines are easily swapped.

Jack.

[Forumadmin]

I have just looked at the original Jowett issued bulletin. It makes no mention of engine or chassis number. It is also definitive in saying 'effective from' rather than 'approximate introduction' that Bob Jones headed the column. I would suggest that the chassis number is the definitive number on the car but if you have an engine and are looking for its modification level then look where Jack says, but also check that there is no plate on the clutch housing indicating a reconditioned engine.

The relevant bulletins were issued in March 1950, November 1950 as Item 1 and Item 1A respectively.

The Bob Jones and Mike Alfrey documents refer to these. There was a third source compiled mainly by Harry Brierley in the 1970s onto wax Gestetner pages. These formed the JCC Technical Handbook. Bob took on the task of bringing this into the 21st century in 2001. Many of the JCC Technical Handbook pages were scanned onto Jowett.org many years ago prior to Bob doing that. I received a copy of the original but have not scanned it in. Something for the Legacy Project perhaps.....

The Jowett Technical Information bulletins were issued between July 1946 and October 1951 in three sections. 1=Javelin then Jupiter, 2= Bradford and 3=General Spares Information. The latter covered models from 1930 right up to the Jupiter and even lists price changes to spares!

This is a bit like retranslating the bible from the tablets and scrolls!

[Forumadmin]

Robin,
Does your Chassis number not have a prefix such as E0/PA/ before the number?

The engine will also usually have crankcase numbers on each half. These also require some cataloguing and explanation.
The gearbox is the only other part with a 'serial' number and thus is important.

[Alf Heseltine]

Yes the Chassis No. is the all important item, everything else can change over time, engine or documents etc.

The Chassis No. can often be found on the 'support bar' for the bonnet catch bolt, the Ch.No is to the left of the catch bolt on the flat surface.
It may be hard to find under the paint, mine was.

Alf.

[Robin Fairservice]

Where is a Javelin engine number? Certainly not on the identification plate which only shows the body number. My engine nas a block number 10742, but the chassis number is 10010 D, and I have no reason to suspect that this is not the original engine. According to the club's records my car was shipped from England on August 21, 1950 and is a PB. We don't have log books in British Columbia, as in England, but my Registration document just quotes the Model and Chassis numbers.

Hi Robin,

I think we are all looking at the number stamped on the raised plinth on the right hand side of the engine (viewed from the front) which certainly seems to match the chassis number on many very original cars.

Of course this number could be different on those cars where the engine has been swapped for another, and I suppose might give a clue to where the engine came from. But none of the numbers referred to in the documents are in the right format to be anything other than the matching number from the chassis, so perhaps should really say chassis number - I suspect as the technical notes are quite focused on the changes to the engine and gearbox it makes sense to identify them by this number, but of course if we are looking at cars (and what they should be or were as they left the factory) it is easier to work from the chassis number as engines are easily swapped.

Jack.

Thanks Jack for reminding where it is. My engine number is the same as the chassis number.

[Chris Spencer]

My engine number is the same as the chassis number.

Robin - In that case you have a very rare car, very few Javelins that have survived through to today will be a matching numbers vehicle - i.e. - still retain the original engine with the original chassis / bodyshell

[Robin Fairservice]

The car was off the road from 1958 until I acquired it in 1995. It had about 42,800 miles on the Odometer. By the way there are casting dates on the cylinder heads, which, on mine, tie in well with its shipping date.