oily plugs

[myoldjalopy]

Sorry to hear about your engine
I agree with Palacebear. A 948 engine and gearbox, together with a 4.55 diff will give you much improved performance compared to the very modest 803.
To avoid chopping the floor of your car and having to fit a 948 gearbox tunnel, which would be required to get the standard 948 gearbox and its remote gear shift mechanism in place (and you would probably need a 948 carpet to cover the different gearbox tunnel), you can 'marry' the 803 box rear casing with the 948 bellhousing, thus dispensing with the remote shift and retaining the long 803 gearstick.
If you do this, it is best to retain the 803 reverse gear selection mechanism (which allows lifting the gearstick to engage reverse, as with a standard 803) by swapping the reverse selector rod out of your 803 box to the 948 box. Otherwise, due to having removed the 948 remote selector mechanism, there is the potential to accidentally shift into reverse gear when trying to select fourth on acceleration.......the resulting ‘crunch’ would not be good!

[pde2000]

Thanks for the advice on upgrading. I have a spare box, so could fiddle around with a 948 box in advance of the change. I might try for replacing the bearing shells with 10thou unders, and even get the local mechanic to have a go for me. There's a little bit of welding needed anyway. There seems to be a few old sets of bearings on ebay for a fair price.

If the engine was changed would the DVLA have to get involved?

[myoldjalopy]

Only, I think, if you change the size of the engine.....when I went from an 803 to a 948 I had to inform DVLA.

[pde2000]

Only, I think, if you change the size of the engine.....when I went from an 803 to a 948 I had to inform DVLA.

Thanks thats what i meant. I wonder if the MOT requirement would come back into force then. I do fancy struggling on with the old engine anyway, if it can be done relatively pain free.

It's funny as I have been steadily getting the car working better, with the brakes even provoking a skid now, and then it does a last hurrah. I dont suppose i can just replace the big end bearings, or will the main ones need doing too?

[philthehill]

Only if you know what the size of the bearings that is both main & big end should you purchase new bearings.
If you fit the wrong size the engine may not turn over or rattle and have low or no oil pressure.
When the engine is stripped you may find that the crankshaft needs regrinding so you should be in no rush for bearings.

[palacebear]

I wonder if the MOT requirement would come back into force then. I do fancy struggling on with the old engine anyway, if it can be done relatively pain free

You will definitely need to inform the DVLA of an engine change (change of capacity and change of engine number.

If by MOT requirement, you are asking if you'll lose MOT exemption status, the answer is 'no'. MOT exemption is based on first registration date of the car, which won't change.

My Series 2 (1956) had a 948cc engine, dating from 1961 and is still MOT exempt, although I have it tested anyway.

[myoldjalopy]

You will definitely need to inform the DVLA of an engine change (change of capacity and change of engine number.

That is true, although, when swapping like for like, its a safe bet many don't bother about the engine number. DVLA would also want to know about changes to the vehicle's colour - and other stuff recorded on the registration document.

[greendefender123]

That's if the dvla will believe you. We had to get a garage to write a letter on headed paper as proof on my father's landy. I know someone with a Rickman Ranger (escort based kitcar) who changed the engine from a 1300 to 1600. They wouldn't except it even with photographic evidence and the receipt for the engine. So he just insured it as a 1600 and saved £50 on tax every year. He had all the proof that he had told them incase of any problems.

[myoldjalopy]

Just another thought about engine and gearbox swaps, 803 to 948. I have a feeling that if you chop the floor and fit a later transmission tunnel (plus the carpet change!) to allow the 948 remote shift mechanism to fit, you will then find the gearlever is fouled by the SII handbrake lever, requiring fitting a later handbrake lever. So the hybrid 803/948 box seems a much better solution all round and does preserve the originality of the SII interior, allowing an easy change back to the 803 set-up, if any future owner ever wanted to return to, shall we say, more sedate motoring......

[pde2000]

Oh the irony, I just had a nice chap walk up to me and offer to buy the car, and had to tell him about the new developments. I promised to inquire about the cost of a rebuild, and a local garage has quoted £800 to £1000, depending on what needs doing. They can regrind the crank themselves, or ESM can supply a recon with the full set of bearings. A friend who drives an a30 has suggested dropping the sump and fitting a set of new conrod std bearings, and just go from there. At least it might be a goer. For sure the steel that the crank is made from is a lot harder than the white metal of the bearings. Spending a thousand on a car that is worth marginally more than that is not an economic proposal.

[liammonty]

Oh the irony, I just had a nice chap walk up to me and offer to buy the car, and had to tell him about the new developments. I promised to inquire about the cost of a rebuild, and a local garage has quoted £800 to £1000, depending on what needs doing. They can regrind the crank themselves, or ESM can supply a recon with the full set of bearings. A friend who drives an a30 has suggested dropping the sump and fitting a set of new conrod std bearings, and just go from there. At least it might be a goer. For sure the steel that the crank is made from is a lot harder than the white metal of the bearings. Spending a thousand on a car that is worth marginally more than that is not an economic proposal.

Just replacing the big ends is, I'm afraid, likely going to be a waste of time. the metal form the damage is likely to have 'taken out' the mains as well, and to be honest, you need to strip the whole thing to assess the damage. It would be folly not to.

If you plan on driving the car hard (as it seems you have done ), I personally would pick up a second-hand 948 engine for one or two hundred, and drop that in. they are FAR more robust, and FAR more powerful. If funds permit, mate it to a 948 box (you can fit the 803 gear lever as detailed numerous times in previous threads), and also the 948 4.55:1 diff. Those changes will transform the car. For what it's worth, I don't believe the 803 box is weaker than the 948 box (having stripped both kinds myself) - they are however both weaker than the ribbed case 1098 box. The issue with the 803 box is the gearing - as you will know, the ratios are poorly spaced (very low 1st, 2nd and 3rd, with a huge jump to 4th) - the 948 has far better chosen ratios. It's around 10 years ago now, but I sourced an engine, gearbox and diff for the grand total of £175 - considerably cheaper than the quoted price of rebuilding your inherently weak engine, even if you had to pay for a garage to do the swap.

Finally, my comment about driving the car hard isn't meant as a dig - I drive my Minor hard - it's just that if you do, your replacement 803 will likely die once more fairly quickly. You are not the first to experience this with an 803 engine... They were poor, and had a reputation for being so even back when they were being produced, I believe.

[palacebear]

To concur with liammonty's post above. The 803 engine could have a very short life if driven hard. The history with my 1956 car shows a visit to the garage in July 1961 (29,900 miles) to diagnose an 'engine noise' followed by another visit two months later to 'supply and fit factory reconditioned (Gold Seal 948cc) engine.' Over the following 56 years and 57,000 miles, the engine still performs pretty well, but the gearbox, (still the original 803 box) although there's no jumping out of gear and no worn synchros, is really, really, REALLY noisy, due to worn mainshaft bearings!

[pde2000]

Fair enough. I will look out for a good 948 engine and get the garage to help me fit it. Kind of seems a shame to ditch the old engine, but they are a bit crap. For now the car is under cover and wont be going anywhere for a while. Over and out.

[ampwhu]

Best options are rebuild your current engine or give it a 948 transplant. You'll be very lucky to find another 803 that doesn't need some sort of rebuild. If you go down the 948cc route, change the gearbox as well. The 803 box won't last long behind a bigger engine. Throw in a 4.55 diff as well. There's a few threads on here covering the pro's and cons of it and giving guidance regarding things like swapping the gearbox tails/keeping the long gearlever etc.

i'd disagree about the 803 box with a 948 engine. I had this set up for years until I fitted 948 internals into the 803 box. (nothing wrong with the box, wanted to improve gearing). it depends on how you drive it. I did around 30K miles without any problem. I friend has a 1275 with an 803 box and he drives it daily.

[palacebear]

Its perhaps fair to say that others will almost certainly have different experiences. I can only draw on my experiences with my own Minor. Its largely complete service history indicates a lack of maintenance over the first two decades if its life, followed by many years of disuse. Doubtless this has impacted on the level of deterioration, and wear and tear now evident.

[pde2000]

Little update; replaced the big end shells with std size, and only one was damaged (3). The crank has worn at 3 too, so that piston still knocks under load. Disconnecting that plug silences the knock, but that's not a solution. When the weather gets better I am going to drop the sump again and measure the worn bearing diameter before ordering a new set of undersize shells (but will only replace the one). I reckon the low oil pressure that's been a problem for many years was that no.3 bearing and oily plugs had been protecting it. No.3 has always got oily first - probably didn't get an o ring last time I did the head. Also have to pull no.3 spark lead off to lift out the dipstick and it sometimes gets forgotten and left off. The 803 needs all 4 cylinders really.

I know the crank really needs to come out and either be swapped or machined, but my intention is to just keep limping on if i can.

[oliver90owner]

You will do as you please, and not heed advice. Likely the limping will not be for an extended period, even if it will turn over with undersize bearing shells. Utterly uneconomic, in my opinion.

[liammonty]

It really does need rebuilding. Limp on it may briefly, but it won’t last for long - particularly if it’s already knocking! Replacing bearing shells without having the crank ground is in this case folly. I’d put money on cylinder 3 having shot rings too, given the state of the rest of the engine - the problems aren’t going to be down to an o ring! You said previously you didn’t want to spend too much on a rebuild as it wouldn’t be worth it given the value of the car, but the problem with thie approach you’ve taken is that whatever you’ve spent on this work is a total waste. Why not just buy a second hand 948 for £150 and be done with it?!

[pde2000]

I have been looking for a good 948 for that sort of money for a few months now, and nothing has come up. The shells cost about £50, and undersize ones can be had for less. The rings are good (compression is ok). Only done a couple of thousand miles since the engine was rebuilt with new rings.

To be honest, i dont feel competent or strong enough to swap engines myself anyway. But thanks for all the kind words.

[ampwhu]

once I removed the 803 from mine, I made a coffee table out of it! nice bit of square smoked glass bolted on top, it looked the business.

unfortunately, it had to go when 'her indoors' kept complaining she couldn't move it to hoover!