803 engine. How fragile?

[Edward1949]

The bottom end seems to have gained a bit of a reputation. When they were just cheap old bangers they were a popular buy, I owned a couple as did various friends over the years. I don't remember the engines being particularly noted for bearing failure. I also remember them as smooth-running, but certainly underpowered even by the standards of 50 years ago.
Any comments from 803 owners? Are you constantly replacing bearings?

[ManyMinors]

The bottom end seems to have gained a bit of a reputation.
Any comments from 803 owners? Are you constantly replacing bearings?

No. Not since we threw the dreadful 803 engine away and fitted a Minor 1000 engine instead

[myoldjalopy]

Oh, this old chestnut again! Yes, bottom end failures were reported but, if driven modestly (you shouldn't really try to cane an 803cc engine - and there's no point anyway!) they will go on OK. I have driven 803's in the past for years without issue but, like 'ManyMinors' swapped in a 1000cc engine to mine about 10 years ago, but more for better speed and acceleration than fear of the bottom end giving out. I kept the pudding-stirrer gearstick though, by mating a 1000 with an 803 gearbox, to avoid chopping the floor

[JOWETTJAVELIN]

The bearing metallurgy was not as good as what came later (948), also they had by-pass oil filtration which is a very well documented weak point when used with modern oil filters. Carburettion is also restrictive. Once I rebuilt mine it was fine but painfully slow, I sold it soon afterwards and would not go back to anything pre-1955 unless it had a large engine and tall gearing. They are best left as historical curios and I would encourage the few survivors with correct running gear to be left alone to show just how awful BMC was in its early days.

[jagnut66]

I kept the pudding-stirrer gearstick though, by mating a 1000 with an 803 gearbox, to avoid chopping the floor

I can understand that from an asthetic point of view but I thought the 803 gearbox had a reputation for being weak and wouldn't cope with a larger engine long term?

They are best left as historical curios and I would encourage the few survivors with correct running gear to be left alone to show just how awful BMC was in its early days.

Too late, I've swapped mine out for a 948 unit attached to a 1098 gearbox and rear axle. I love the looks of split screens, I just want to be able to drive it up hills, on a regular basis, in somwthing less destructive than 1st......
Best wishes,
Mike.

[liammonty]

How fragile? Ridiculously...

In my experience, the poor reputation is justified. the bottom end gave up without warning on my 803, which had excellent oil pressure at the time of failure. As JowettJavelin says (and I recall him suffering failure of his 803 around the time I did!!) there are many design weak points compared to the later 1000 engines - small crank journals is yet another contributing to the weakness. David Vizard describes the 803 crank as a 'bent piece of wire'. Compounding all this is the fact hat due to the woefully low power, they have to be driven relatively hard, and they just don't cope. The earlier sidevalve is gutless, but robust.

Regarding the comments on the strength of the 803 box, I've never understood their reputation for weakness, given that having had my 803 box and a 948 box in bits alongside each other, I'm not aware of significant differences beyond the remote control and gear ratios. It's the ratios that are the issue, with a ludicrous gap between 3rd and 4th. The 1000 box ratios are far better (as is the case in my Series MM box!). I put a 948 engine, box and diff in my early SII when the engine died, and it transformed the car.

[myoldjalopy]

"I can understand that from an asthetic point of view but I thought the 803 gearbox had a reputation for being weak and wouldn't cope with a larger engine long term?"
Hello Mike - no, what I meant was I created a hybrid gearbox by 'marrying' a 948 box with an 803 box i.e. join the 803 rear casing to the 948 box bellhousing, so the remote shift is removed from the equation. You need to fit the 803 speedo gear onto the 948 main shaft, and also swap the 803 reverse selector into the 948 box, to retain the lifting of the gear lever to select reverse - otherwise you could accidentally shove the box into reverse whilst trying to select 4th!
Anyway, what you effectively get is the 948 gearbox internals in an 803 casing, retaining the 803 gear lever and not chopping the floor

[liammonty]

myoldjalopy - that’s exactly what I did to mine. I discovered about the speedo drive difference the hard way so had to remove the box again to rectify that as the Speedo read 50% high

[jagnut66]

Hello Mike - no, what I meant was I created a hybrid gearbox by 'marrying' a 948 box with an 803 box i.e. join the 803 rear casing to the 948 box bellhousing, so the remote shift is removed from the equation. You need to fit the 803 speedo gear onto the 948 main shaft, and also swap the 803 reverse selector into the 948 box, to retain the lifting of the gear lever to select reverse - otherwise you could accidentally shove the box into reverse whilst trying to select 4th!
Anyway, what you effectively get is the 948 gearbox internals in an 803 casing, retaining the 803 gear lever and not chopping the floor

Ahhhh, I see....
Interesting but how do the gear ratios compair, using a 948 box (internals at any rate) on a 1098 engine?
Best wishes,
Mike.

[myoldjalopy]

Well, I'll leave that to someone else, as my 'hybrid' box is matched to a 948cc engine.......but it is a marked improvement on the poor old 803, without doubt.

[jagnut66]

Sorry, when you said '1000cc engine' I thought you meant 1098.
Best wishes,
Mike.

[myoldjalopy]

Hi Mike, yes I should have been more specific. I always think of the 948cc engine as being a 1000 and the 1098cc version as an 1100. The introduction of the 948 in late 1956 was accompanied by the change of bonnet badge from 'Morris Minor' to 'Minor 1000'. But they didn't change the badge again for the introduction of the 1098cc engine..... Come to think of it, the bonnet badge on the Minor Million might have suggested a very large engine in that particular model!

[jagnut66]

But they didn't change the badge again for the introduction of the 1098cc engine

Possibly because they already had a Morris 1100 in the planning stage by then?
I believe the Morris 1100 was actually introduced in 1963 but back then cars could have a long development period. By this I mean that it might have already been in development when the 1098 engine was introduced into the Minor in 1962.
Best wishes,
Mike.

[SteveClem]

My 1955 A30 is still running fine on its original 803 and gearbox. But ,yes, it is ridiculously slow and really little more than an attractive curiosity. Certainly not a car for everyday use in the 21st century

[liammonty]

My 1955 A30 is still running fine on its original 803 and gearbox. But ,yes, it is ridiculously slow and really little more than an attractive curiosity. Certainly not a car for everyday use in the 21st century

I always understood that as the A30 is a little lighter than the Minor, the 803 managed a little better in the Austin. Does it have an SU on it, or has it got a Zenith like the 948s in the later A40 Farinas, which robbed the 948 of 3 bhp versus the SU carbed version in the Minor? Just wondering if the version in your A30 is even less powerful than the version in the SII Minor!

[ManyMinors]

But they didn't change the badge again for the introduction of the 1098cc engine

Possibly because they already had a Morris 1100 in the planning stage by then?
I believe the Morris 1100 was actually introduced in 1963 but back then cars could have a long development period. By this I mean that it might have already been in development when the 1098 engine was introduced into the Minor in 1962.
Best wishes,
Mike.

Actually, it was the other way around. The launch of the Morris 1100 was in August 1962. So pre-dated the Minor 1000 engine upgrade to 1098cc by a month or so

[jagnut66]

Fair enough, however that also confirms why they could never use the 1100 moniker on the Minor after it acquired the 1098 engine, imagine the confusion....
Best wishes,
Mike.

[ampwhu]

My 1955 A30 is still running fine on its original 803 and gearbox. But ,yes, it is ridiculously slow and really little more than an attractive curiosity. Certainly not a car for everyday use in the 21st century

I always understood that as the A30 is a little lighter than the Minor, the 803 managed a little better in the Austin. Does it have an SU on it, or has it got a Zenith like the 948s in the later A40 Farinas, which robbed the 948 of 3 bhp versus the SU carbed version in the Minor? Just wondering if the version in your A30 is even less powerful than the version in the SII Minor!

yes the A30 is lighter and the 803 does last that little longer. I too have an A30 still and changed the 803 around 10 years ago when i was going flat out down the M4 at around 45mph. That was enough for me. The A30 these days has a morris 1098 in it with a modified gearbox with 1098 internals. It drives lovely.

My split screen lost its 803 before i bought it 30 odd years ago so don't know the story behind that.

[SteveClem]

My 1955 A30 is still running fine on its original 803 and gearbox. But ,yes, it is ridiculously slow and really little more than an attractive curiosity. Certainly not a car for everyday use in the 21st century

I always understood that as the A30 is a little lighter than the Minor, the 803 managed a little better in the Austin. Does it have an SU on it, or has it got a Zenith like the 948s in the later A40 Farinas, which robbed the 948 of 3 bhp versus the SU carbed version in the Minor? Just wondering if the version in your A30 is even less powerful than the version in the SII Minor!

I did put a SU on, the Zenith was a pain in the neck! It helped a bit...

[Edward1949]

The earlier sidevalve is gutless, but robust.

Interesting comments.
Perceptions of gutlessness change over the years. 50 years ago I toured France in my heavily-laden 1950 side valve, basically the pre-war Morris Eight engine. I never felt aware of being particularly slow, there were plenty of vehicles cruising at under 50 mph even on Motorways. In those days there were still plenty of early Citroen 2CVs on French roads which the Morris easily left trailing behind on long climbs with its stonking 27 bhp versus the Citroen's 12 bhp !