1HD-FT bearings

[Yawood]

...it's cheap and a better alternative to a hole in the crankcase.

Actually there is virtually no chance of a bearing failure causing a rod to go through the crankcase - now a bolt failure is a different matter.

If the bearing wears past the sacrificial material, and the noise is still ignored, then the harder bearing surface starts to wear the crank journal. This means that the crankshaft will need to be replaced or re-ground which requires removing the engine in order to remove the crankshaft -- so, do the bearings before that happens or the job becomes substantially bigger. At the extreme, if even that noise was ignored, the crankshaft may wear sufficiently to break or at least start to wobble in the main bearings thus wearing them etc etc. So, as you said, doing this fairly simple job early is very good insurance against a much bigger job later on (and once it starts to go, the bigger job is not much later).

I did my first BEBs on my sister's Morris Minor when I was 19. She had lent me the car when I was working in a country town in NSW (Oz) and boarding at a house near work. With only a basic roll of tools and a workshop manual, I replaced the BEBs only to find that it didn't fix the problem because I hadn't measured the journals and they were worn. So I removed the engine and sat it on a box in the backyard, stripped it down, removed the crankshaft, hitch-hiked to Sydney to get an exchange crankshaft, hitch-hiked back, installed it with new mains and BEBs and got the car up and running again.

 

[frank rabbets]

I started out on Morris Minors. The 803 cc engine got through big ends at an alarming rate. I bought a 950 cc engine and rebuilt it but the crankshaft broke. I did the 40 mile journey home OK with no worsening of the rumbling noise and a constant 7 psi. I had a 4 inch diameter oil pressure gauge in there I was so paranoid. It had broken across the front web which meant it span as if in one piece. Big ends were perfect !! I had to buy a short engine which the main dealer drove out to my home just with a phone call. I paid cash and he drove off. How times have changed.

 

[flint]

Ah, simpler times indeed, head gasket job on a Moggy a couple of hours at most on a slow day. Going back even further, I can remember my dad overhauling the engine from his Standard Flying 8 on the kitchen table (didn't go down too well), took him an evening.

 

[Yawood]

My first car was a 1948 Hillman (the one with the suicide front doors). One day on the way to work in 1963 there was an almighty crash and bang so I stopped it on the side of the road and hitched to work. When I got it home that night and removed the head, three pistons were up but one went down when I pushed on it. It turns out that the piston had let go at the gudgeon pin. It left the top of the piston at the top of the bore and the rest in a million pieces in the sump! Sorry, off topic.

 

[clivehorridge]

Actually there is virtually no chance of a bearing failure causing a rod to go through the crankcase - now a bolt failure is a different matter.

If the bearing wears past the sacrificial material, and the noise is still ignored, then the harder bearing surface starts to wear the crank journal. This means that the crankshaft will need to be replaced or re-ground which requires removing the engine in order to remove the crankshaft -- so, do the bearings before that happens or the job becomes substantially bigger. At the extreme, if even that noise was ignored, the crankshaft may wear sufficiently to break or at least start to wobble in the main bearings thus wearing them etc etc. So, as you said, doing this fairly simple job early is very good insurance against a much bigger job later on (and once it starts to go, the bigger job is not much later).

Not necessarily disputing this, but when the white metal has shredded, there's often enough free play for the hammer effect to crack and fracture a BE cap, especially on high compression engines such as the diesel 80.

A broken BE cap at running speed would throw the con rod straight through the side of the crankcase, no problem, I've seen it too many times.

But, we agreed on the cure, quick cheap and painless, even if you find your bearings are good, it's the peace of mind factor that counts.

I had a similar experience to Frank, on my A30 (A series 1071cc engine) when the crank broke on a diagonal on the centre main journal, it kicked up a hell of a racket, but it drove me home!

Yep, good old simple mechanics days they were.

 

[karl webster]

I'm afraid I have to agree with Clive and I've also seen it more than once on an 80 engine also on the 100 series.

 

[flint]

It used to be called “putting a leg out of bed” when it happened on lorry engines, I worked at the Walls (sausages and ice cream) maintenance place in Park Royal for a short while and it happened on one of their AECs, big hole in the block.

 

[Yawood]

Not necessarily disputing this, but when the white metal has shredded, there's often enough free play for the hammer effect to crack and fracture a BE cap, especially on high compression engines such as the diesel 80.

A broken BE cap at running speed would throw the con rod straight through the side of the crankcase, no problem, I've seen it too many times.

Absolutely Clive (and Karl), there is no doubt that this can be the consequence. I know it is semantics but it is not the worn bearing that causes that, it is the broken cap or bolt or whatever. So, I agree wholeheartedly that a worn BEB can lead to other catastrophic failures but the wear on the bearing itself won't throw a rod. Sorry, it is the pedantic engineer in me coming out.

It doesn't change the fact, as you said, that doing the bearings early rather than too late is great insurance, especially as it is not too expensive and fairly easy to do.

 

[frank rabbets]

Crankshaft journals are much harder today than years ago. If you have a ticking big end these days the crank is probably OK but years ago once you heard that noise it meant a crank regrind.

I had a 1989 2.2 audi coupe. I used to corner so hard that the oil would be almost horizontal and the low oil level alarm would scream. On leaving the corner the pressure would build up again. After driving like this for 12 months or so a friend told me the engine sounded rattly. I had got used to it. But yes on revving whilst under the bonnet I realised the big ends had gone. No damage to the crank though.

 

[Yawood]

We talk about mechanical woes in the earlier times.... If you haven't already read it I thoroughly recommend the book "Mailman of the Birdsville Track - The Story of Tom Kruse". Tom did the outback mail run from 1936 in a Leyland Badger. Some of the bush repairs were amazing, like using the top of an oil drum as a clutch plate. It was also a film made in the fifties and is available on DVD.