Engine Colour

[casper171072]

I was having idle thoughts the other day about something that is now bugging me to the point I need to find out what is right.  Why are some of our engines Morris green and some MG red?  My engine is red, all be it completely the wrong shade.  My brother has two One Point Fives, one engine is red the other is green.  A look on google images shows both. Was it a random thing or was it a change in year, if so why the change?  Its a pointless matter I know but there you go :-) 

[Mabel]

Casper. Interesting question. Could it be a recon engine perhaps?

My 1960 1.5s engine is red but then again I think the owner before me may have painted it during the restoration work he undertook.

[canuck]

Jun 12, 2018 13:33:01 GMT casper171072 said:

I was having idle thoughts the other day.Why are some of our engines Morris green and some MG red?  My engine is red, all be it completely the wrong shade.  My brother has two One Point Fives, one engine is red the other is green.  Was it a random thing or was it a change in year, if so why the change?  Its a pointless matter I know but there you go :-) 

An idle thought you say? ummm! I have so many I could keep this and many other forums very populated!   

I think Roger is a good guy to pipe in on this. He seems to have a very solid handle on the history of this little orphan of ours.  The engine ID number pre fix is either 15R or 15RB for sure. 

My thoughts are model changes? MK1 being MG Maroon?, MK2 & 3 being Austin/Morris Green? 

So; 

My car is a MK1 like Grahams hence the engine is MG Maroon in colour.  I have only encountered MK1 cars as they were the only model imported, in any great number, over here. All engines are MG Maroon.

And yours Casper? MK1, 2 or 3? and your Brothers cars?  I wonder what the poor cousin Wolseley had for the  engine colour?

Just to add confusion the factory brochure doesn't help much with this, and presents an identity crisis of colours.

Back to you lot

Bruce

[casper171072]

Yes I also had looked at the brochures which is confusing. My car is a Mk1 which supports your theory as to the Mk1's being red. My brother Mk1 is red and his Mk3 is green so looking good for that theory :-)

[canuck]

So where is Roger? He must have some Riley history to share?

B

[noddy]

Hi Bruce,
Sorry - been away - its Le Mans weekend! - so have been at a friends camping, drinking and having a good time 

Anyway  back to the query ....
Basically the early engines were painted MG Maroon red - especially as the first 150 pre-production cars were built in the MG Abingdon factory. The paint then seems to have stayed red into the full standard production run of Mk1s.

However it is not clear when they changed from red to the more common Morris green. There is no written evidence, that I have seen, noting the change over of colour. My best guess is that the engine colour changed when the engine numbers changed from 15R to 15RB - approximately at chassis number HSR1-10701. This would seem the logical point for the change.

I can say that I have never seen a Mk2 or 3 with an orginally red painted engine - and I doubt if there are any Mk1s after ch.#10701. Despite saying this I am sure someone will come forward with a later Mk1 car saying they have a red engine - and blow my theory out of the water 

My old car, #12422, has a green engine and my current car, #3902, has a red engine - so they fit in with my theory - but Im ready to be proved wrong!

Hope this helps,
Roger

[tjt77]

Originally the 1.5 engines were painted 'MG maroon"..this was changed to 'austin green' with introduction of the Mk2 models (1960 year model) .
Speculative reasons and more info :- It may be that this was due to the first batch of cars being produced at Ablindgon (MG factory) and the engines were probably built at same plant as those of the MGA which is almost identical ( the 1.5 has a different camshaft and distributor advance curve to match the cam.( same distributor and cam grind as the 1.5 was used on the ZB Magnette) otherwise the engine is internally and externally identical that of the late MGA 1500.. the 1.5 uses the same type of carbs and same inlet manifold ,but with smaller (Mk1 sprite size) float bowls which are located on inside between the carbs, rather then outside at the ends on the MGA.. this was to avoid issues with hitting the clutch master cylinder on LHD cars .. the Riley 1.5 has the same quoted power output as the first MGA ( 68 BHP) @ 5400 rpms but post 56 the MGA output is listed as 72 bhp @ 5,500 rams... likely the camshaft is the reason for extra bhp on the A engine.. .although the riley cam was recommended as a tuning option to produce 'more mid range horsepower" which is bunk... the riley cam produces more mid range torque at the expense of less brake horse power at top end.. there is some literature stating the riley cam was 'modified' on later cars ( believe to facilitate less noise) and in my experience the Mk1 cars have a performance edge and are more lively compare to the the later ones.. an early modification to prevent cold running issue due to sticky hat tubes , is to replace the carbs with .later design set from an MGB.. the old H style SUs were deemed 'obsolete' and the 1.5 is the ONLY production car to use this type of SU after 1962.

[tjt77]

Whilst at it, and of subject :- another note on the carbs ..(I'm no fan of the std H type SU..too many shortcomings with them) the Farina BMC cars with twin carbs ( riley 4/68 and 4/72..Mg magnette only) came with a unique carb and maniifold set up ..they used an alloy inlet manifold bolted to the cast iron exhaust manifold.. which is same style in terms of its flow and outlet as the 1.5 and Z magnette .and also uses an 'oil bath' filter . the carbs used on these cars are SU 'HD' ( same as Jaguar and other more costly cars) which do NOT have the cork seals that cause annoying and potentially dangerous leaks and sticking choke ..this set up can be bolted on to a 1.5 with no modifications.. as mentioned above.. for UK market cars one can use the MGB carbs and inlet manifold set up.. on LHD cars the only viable option for later carbs is to use the whole set up from a farina twin carb car.

[canuck]

Jun 18, 2018 23:06:25 GMT tjt77 said:

on LHD cars the only viable option for later carbs is to use the whole set up from a farina twin carb car.

Totally off topic so apologies to Casper for the segue.

That HD4 carburetor is like the love child of a Zenith and an SU. Ughh!

Option is one can use/fit the HIF4 type  from intermediate year MGB (USA) cars and late UK MGB cars.

Many H type carburetor owners complain of these sometimes troublesome cork gland seals on the main jet.  What is overlooked by a great many owners is to renew the spring.

These springs are static load at install and do compress over the decades. Replacement goes a long way to seating these new cork glands of the main jet for years to come.

FWIW I have experienced more float chamber holding up bolt grommet drips than jet gland seal leaks.  In any event an afternoon and only a few dollars or £'s for glands, grommets and springs will see these H type carbs up to snuff.

B

[tjt77]

whilst off topic ( apologies Casper.. am laid up for a few days due to injury, whilst I have 2 x 1.5s in the workshop at this time, and another due in next month, Im unable to work, so have time to engage on this suite again...there is always knowledge to share.. )
I'll respond to Bruce on the carb opinion above :-

SU HD carbs have zero relationship to the excreble zenith stromberg carb, which has well known shortcomings, and was first produced as a 'economical alternative' to the SU, in mid 1960s ..well after the SU HD, which had been introduced a decade or so earlier .. there is a very good reason why the HD type carbs were used on cars such as Jaguar, Rolls Royce, Alvis and Rover.. they are better built, more reliable and hold their settings well, and were more expensive originally.. the whole throttle shaft arrangement is better ( wider bushings and double lipped neoprene seals to keep the dirt out) and were built to last longer than the other SUs ..they were fitted to the farina twin carb cars in order to gain reliability. and avoid the well known shortcomings related to H style carbs ( farina magnette and Riley 4/.68 were introduced in '59.. HS type SUs had not been produced at that time.. likely why the more costly HDs were utilized for the job). They dont leak ( unless the diaphragm gets cracked with age.. average 'normal' life of diaphragm is minimally 25 yrs and its a +/-$30 part) the chokes are easy to operate and unlikely to ever stick up..'set up and rebuilding time' is considerably less than with the H type carbs....its an altogether better designed and built carb..with superior arrangement for choke operation, that is why its my recommendation as an upgrade to improve the standard 1.5 set up and have one less potential 'problem' to deal with ..( again RHD cars can upgrade to the far more common MGB set up.. 2x HS4 .. manifold bolts right in and the complete MGB linkage can be used)

The H type SU was deemed 'obsolete' by '61 and replaced with the HS in most applications.. MGA continued with H type till end of production in early '62..Riley 1.5 had them till end of production run in '65.. Wolseley 1500 went over to a single HS for the '61 model year I believe ..along with other B series powered cars that used the same manifold set up .. I first used an HD carb conversion in '69 on my 1.5 (my second ever car) .. the complete farina set up including manifold..had to resolve that sticking choke and the accompanying 'flat spots' when cold..along with that drip drip drip of highly flammable petrol. .

The original H type carbs can be improved by replacing the compressed cork seals (an unstable material that shrinks when dry and expands when wet) with high grade O rings.. Moss Motors keep em in the correct size and meterial..their part # is 365-420.
(careful inspection of every component,espcillay wear on the outer surface of jet tube and for any other 'issues' along with very careful assembly is essential to help them to operate as they were designed to do..but dont expect them to be trouble free..there are a lot of 'critical' parts which have to be assembled in correct sequence, and the original cork is a lousy meterial to use as seal for gasoline..period.) there is an added 'bonus' for originality enthusisasts :- you can retain the oil bath oil filter air filter provided the farina casting that attached filter to carbs is retained.
I personally I ditch this and use the Vokes filters from the MGA ..same design and meterials used as modern K&N filters.. induction noise has never been an issue Ive noticed..