Cadillac WW2 Flathead 5G Serial Prefix info

[Joey]

Hello everyone, I appreciate the site and it's info and thought I would log on and throw some more out there in regards to Cad war motors. There are old discussions on here discussing motors with serials that start with 1G, 3G, and 4G, and no info on the mysterious 5G. Info states that 1G was stuart tank, etc. but what was the 5G? I just picked up a crate motor and trans. It starts with 5G. It's pulley set up is not like any other tank configuration as it does not allow the generator off of the front hanging forward like the Chaffee. and does not match the Stuart either. It has the shaft for a fan behind the block, and interestingly has a governor on the distributor. The block has casting for side mounts (Stuart style) but instead uses timing cover and rear tailshaft mounts. I think some tanks mounted like this too (Chaffee?) I have been emailing with back and forth with some great people (thanks Skip of Ropkey Armor Museum!!) to get to the bottom of this.  I also have the benefit of having the original shipping docs, and the Req. number has a UK prefix, spare parts in a box in the crate are labeled as British Eng. Kit, and at the top of the engine parts list it says CT-20 Production Engine. The CT-20 is the "Oxford Carrier." I have not found a pic online yet of the engine bay to confirm but a lot of into points to it being for the british... so maybe the 5G is a british designation?? Here is a link to a bunch of pics....

http://s226.photobucket.com/user/joeyrocketshoes/library/Cadillac%20tank%20motor?sort=3&page=1

[Doug Houston]

I'm retired from the ArmyTank  Automotive command in Warren,Mich.  We never identified a vehicle by those names you cite.It was always by the "M" (model) number. Writers love to call EVERY WW II tank: Sherman!

To my knowedge, there were only two icles tanks that used the Cadillac engine; the M5 and the M24. The TM's for these vehickes tell a lot. There were landing crafts (I believe)  that also had Cadillac engines.

The only usable parts of those ebgines would have been the short block, with appropriate pipe plugs. Whatever other applications there were for the engines is anyones guess.

I could speculate on the letter code in the vin,  but I'm not sure of that.

[Steve Passmore]

What a super find that is. Didn't think there were many crate examples left these days.   These engines had a variety of uses here.   One I have was intended for a 'Motorized Gun Carriage' maybe 'Anti Aircraft'  The short block needed no modifications to fit a car. Also have one from an M24 thats completely different and Doug is correct they were used extensively in landing craft here.  This marineized type needs much more work to fit a car. 
The upside down starter is a weird feature, non of mine has that. If it has a governor it was obviously intended for a situation where no one was in control of the throttle?  I have seen large American engines powering our air raid sirens so who knows?    Cant help with that 5G though. John Tozer may know more.

[Joey]

CT-20 being a tracked vehicle but does this look marinized?

[tozerco]

I was just about to flick this one to you Passmore. I feel a new research project coming on. I think, without ever having seen either a G4 or G5 engine over here, but having seen 3F, 1G and 3G engines in all sorts of stuff from Cruier Tanks to searchlight carriers, it is safe only to say that, during war, Cadillac would probably have made just about anything that one of the allies asked for. That is one great looking original engine and maybe the Cad Museum should grab some examples of this extremely important period in the company's history before they are all gone. I'm off to the filing cabinet and the computer for some more digging. A full set of photos from that crate engine to start with....

[tozerco]

Hey Passmore, I read somewhere that the Poms had a plan towards the end of the War to put Cadillac engines into the old Matilda tanks.... Don't know where I read it but I'll see if I can find it. I think I read that the impending end to the War put an end to it but it would be pretty well right for time if the 5G was part of that plan.

[Joey]

I intended to hang onto this crate motor a while but I have some other financial obligations I hope to take car of by selling this motor to someone to display or restore a WW2 vehicle. It is on ebay. We will see if it goes or not. It is an expensive opening bid ($10K) but to the right person... not so much. I restore vehicles for customers and have done some $100k plus restos and $10k for a rare drivetrain that is impossible to find that is needed to complete the restoration would be a non issue. Time is money, and tracking down all the little stuff takes time if it can be found at all, then restoring each piece, etc. Here it is in a complete bundle, zero miles and all the little tags and accessories. And some tanks (Stuarts) are commanding $300K restored. Though there would be some changes to this motor to install in a Stuart but again, at it's core it is usable in many applications.

[tozerco]

This site has a lot of information up to G4:

www.m24chaffee.com/Vehicle Standard (Australian Design Rule 61/02 â€" Vehicle Markings) 2005-flathead-v8-engine-data.html

[tozerco]

.....and this:

http://www.m24chaffee.com/cadillac-engine-photos.html

[tozerco]

Don't know why that first link didn't work. I'll try again. Meanwhile here's something to really delight the flathead fans!

http://g503.com/forums/viewtopic.php?f=82&t=232831&hilit=stuart+engine+rebuild

[tozerco]

Let's try that link again....

http://www.m24chaffee.com/cadillac-flathead-v8-engine-data.html

[Steve Passmore]

The main questions on my mind Joey is where did you manage to find it? but more fascinating is how has it survived in such good condition for the last 70 years?  The last one I saw had the crate rotted away and although new had years of crud rust and grime. This one looks like it was made last year!

[gary griffin]

Jory,

   You have me fascinated here. I am not an expert but have made a few observations after viewing your 59 pictures. Some are observations and some are guesses.
   I would guess the 5G was Cadillac number for a small series of engines or a Special Order designation. My observations are in the same sequence as the pictures but not necessarily an observation for each picture.
    Starter appears to be unusual.
    Markings Cap warning light, Socket warning signal, interior light set, relay starting motor, shaft fan drive-long. All are indicators of ? More than I would expect from that era.
    Receptacle, engine conduit cap warning light socket warning signal. Remote panel??
    Rock Island Ordnance institute? Shipping point for New Jersey to Europe?
    Belle Meade New Jersey Charge to Detroit ordnance division. Ordnance usually means weapons in military speak.
    Existence of forward exhaust crossover.
    Unusual transmission?
    Label British engine kit?
    Governor, This would limit the top speed of the engine to protect it from abuse
    Label heat signal gauge?
    Heat signal gauge
    Cooling fins on coil. Could mean it was going to be installed in a hotter than normal environment.
    Transmission fluid extension. Could mean engine would be in a deeper than normal pit?
    Threaded rod exhaust hanger. The way this is used makes me think of stationary engines, not vehicular engines.
    Unusual hoses at distributor and transmission?
    Welded sump extension? For more oil capacity for cooling or extended periods of no oil changes?
    Unusual transmission?
    3 groove fan belt. Could be to take off power for secondary use such as a fan or pump not necessarily for primary use of the engine.
    Desiccant. Standard shipping moisture absorbent.
    Unusual hydromatic?
    Rear coolant.  Means probably cooled with a remote radiator or a heat exchanger such as would be found in a marine application.
    Hand crank or take off for power?
    Box in crate in front of engine? I would love to know what all is in this small box?
    Cap warning light?
    Socket warning signal? More gauges and warning lights than would have been normal in that era I think.
    Gauge thermal panel. Probably remote control panel.

All of this means very little except it was probably used

It is pretty obvious to me that it was produced for Britain's special needs.

My first guess would be for landing craft or other marine usage? Second would be mobile artillery? Third would be sirens and lights mounted on a powered mobile platform as Britain was being demolished by bombing raids.

The fact that it still exists in new condition indicates it was probably produced near to the end of the war and contract was cancelled.

Great find, I would suggest you contact British military history techno-buffs for more information.

   

[Joey]

It was bought as surplus many years ago by a company and put in a warehouse in a dry arid region of California where it just sat. A gentleman who worked for that company for many years retired and the company also closed its doors. they let him have it. He uncrated the top portion and pulled back the cosmoline wrap. Discarded the rest of the crate unfortunately. They it sat under a blanket for a few years until I discovered it stored in my friends shop. I bothered them about it for a year and a half until he sold it to me. Just before I got it a couple curious guys cut open the cardboard box in front of the motor to see what was in it. All the parts listed on the shipping sheet are packed in there. The box was dipped in a rubbery solution than wrapped in paper. Very well sealed.

[Steve Passmore]

You could only find that in the US of A

[tozerco]

For what it's worth I notice a lot of the packages are stamped "CT20" and this info makes for an interesting possibility....

"The Oxford Tracked Carrier ((Carrier, Tracked, CT20)) was an early post world war two British armoured personnel carrier (APC) and artillery tractor.The Oxford was substantially larger - at 6 tons - than the 3 ton Universal carrier it was designed to replace. It saw service in the Korean war both as a tractor for the 17 pdr and as an APC. Several versions of the carrier (CT21-35R, CT23-26) are listed in Chamberlain and Ellis (1973)".

[tozerco]

I also read that the CT20 had Stuart Light Tank (Chaffee M24 to the Yanks) running gear which would mean 2 x Cadillac V8's if that extended to the engines. The plot thickens.....

[Steve Passmore]

That is very interesting John bearing in mind that these engines as 'Spares' would still have been produced beyond the introduction of the overhead valve if they were required as replacements for vehicles being used in subsequent wars. We tend to think war stopped, so all production changed to cars, but with the Korean war leading into the 50s and the need of spares after that date means this engine could well be newer than we think. 
Guess theres no way of knowing when Cadillac would have actually stopped production of certain spares especially if they were needed be the military of Allied countries?   Our military had 50s style Bedford's for decades after they were no longer available it civilian markets.

[Joey]

Good point but this motor is dated on the motor tags as well as the shipping slip 1944. Here is some great info I found about the CT-20 Oxford Carrier. It states that the RA in britain was expecting 6 prototypes for trials in 1944  but by december of 1944 delays with the Cadillac Engines held up production. The packing slip is dated 11/25/44! Were they waiting on this? Here is all the info I found...


-------The carrier saw use after the Second World War, primarily as a gun tractor. The British Army developed the CT20 Carrier immediately after the war to be able to carry out the various duties still related with carriers, namely carrying medium machine guns and mortars, towing anti-tank guns, Observation Post and reconnaissance duties.

The Oxford Carrier, as it became known, was larger than the earlier Universal Carriers, weighing 6 tons and powered by 110 horsepower Cadillace 5 litre V8 engine with 4 speed Hydramatic transmission. The suspension was similar to the Windsor or T-16, with four road wheels (with steel centres rather than the spoked design) and a front sprocket drive. The British Army used some of these vehicles in the Korean War.2

In the late 1950s, Carrier design was transitioning to the use of fully tracked, fully enclosed Armoured Personnel Carriers; in England the FV432 was developed while Canada worked on the XC1 Bobcat and the US developed the M113.

------Also check out this article. Tim Royall published this in the Royal Artillery Journal as part of an article on the history of the Armoured OP vehicle and also formed part of an article he did for Tracklink (Bovington Magazine) on the Oxford and Cambridge carriers. It was based on material gathered from the library at the School of Artillery in the UK.

"Some time ago I did some research on the Oxford and Cambridge carriers and also visited the private ones. The Oxford definitely didn't see service in WW2.

The RA expected six prototypes for trials in late 1944 but by December supply problems with the Cadillac engines had delayed production and the RA were told to look on the CT20 as a long term project with the Windsor Carrier taking over the role as an Armd.OP for Infantry Divisions until the mid 1950's. Trials carried out between then and July 1945 also showed up defects in the suspension that further delayed production and user trials. At this stage a production run of over 400 vehicles with the Cadillac engine was envisaged with further long term production planned using a British engine of around 180 bhp and the possibility of incorporating overhead cover.

However the end of the War brought about a harsh review of all vehicle projects. Production was severely curtailed but CT20 continued to take place in several trials. In July 1946 it was demonstrated at the high profile "Exhibition of German and other vehicles and equipment" at Chertsey where it was seen as the future. It was described as "the latest type of British Carrier; its welded hull is much more spacious than that of the Universal Carrier. It employs "Cletrac" steering and a four speed hydromatic gearbox in conjunction with a 2-speed and reverse auxiliary box. The engine is a Cadilac V8 developing 110 bhp". It also took part in a suspension demonstration against a Coventry armoured car and a German 8 wheeled armoured car with unrecorded results.

Change continued at an alarming rate due to the conflicting demands of post-war reductions and the development of the Cold War. Between August and November 1946 CT20 was used by the RA as a trials vehicle for a further development, the CT25. This was a later version of the CT20 with a Rolls-Royce engine and improved suspension to take the weight of overhead cover which was not possible on CT20. A mock up of the fighting compartment was also built on an Alecto chassis for design approval before FVDD Chobham produced a mock up on the new CT25 chassis. However by 1946 Vickers were developing a new family of light vehicles called CT26. The RA felt that this was too bulky to be an OP vehicle and too small to be a GPO vehicle but in February 1946 the War Office decided that all future field and medium SP guns were to be mounted on this chassis and therefore their associated vehicles. By September the RAC had changed their mind in favour of what was to become the FV300 series and so the RA also agreed to this series. Little else is known about the CT20/25 series from the RA point of view although the Oxford Carrier served on with the Infantry in various roles including that of a A/T gun tower and even saw service in Korea."

[Steve Passmore]

All fascinating stuff.