Bigends

[regtubby]

We've got that interesting noise that tells us that we have a bigend problem. As the car lives on the street and we can't get it off road for repair it's off to the garage.

Our very helpful (70+ year old) mechanic has tried his best to blind me with some jargon. He always leaves me the fun of getting the parts but I'm afraid I lost him soon after the mention of copper lead and heavy duty bearings! What's he on about and where do I get them?

[newagetraveller]

You should be able to get new big end shells from your local motor factor.

You need to know two things: Firstly the engine size, it is probably 1098cc.

Secondly, whether the crankshaft has been reground in the past. The only way to determine this is by looking at the old bearing shells when they have been taken out. Best to take one of them with you when you order the new ones.

[rayofleamington]

You should be able to get new big end shells from your local motor factor.

make sure you shop around and check prices before ordering! I got heavily stung for Minor engine parts from a local motor factor
Also look in yellow pages for a backstreet engine machinist / reconditioner (place that does rebores and crank regrinds). The engine recon places buy more engine parts than a motor factor and often can get the parts at a fraction of the price.

As mentioned already - you need to get the right size parts. This often involves getting the crank measured - this may have already been done by your first guy before he recommended new shells (rather than recommending a crank regrind because of crank wear...)

[Packedup]

If the crank's good and hasn't been ground before then you'll be fine... If you don't know if it's been ground before then yes, it's time to start measuring...

However, when it comes to buying bearings the local Partco counter (Brown Brothers, but same difference) charged a small fortune for set of big end shells (about 30 odd quid), whereas people like ESM do them for not much more than a tenner! That's for cheapo ones though, your mechanic is probably saying to buy a good quality lead/ copper, as opposed to aluminium/ tin, which are OK but nothing like as good.

Personally I try to pay the extra for the lead/ copper, but haven't had any real disasters with the ali/tin ones so far - I do use my right foot, this has not been in A series engines, and I don't do many miles a year, so make of that what you will

If you're doing the big ends, it's a false economy not to do the mains, and if it's engine out for this then do the pump as well - If one bit's worn to excess, the rest is unlikely to be far behind.

[regtubby]

Thanks folks. Much as I suspected. The supplier the garage use wanted £28 for copper lead. I'll get shopping around.

[brixtonmorris]

just had it done for someone last week.
to regrind crank, supply big end bearings and main bearings to fit.
£80.84 +vat. ae bearings.
inc rebore 30 thou, new pistons, full gaskes set.
timing chain and tensioners, new oil pump.
total for all £386.36 +£67 vat

so that makes a short block at £ 453. 96 in a central london machine shop.
(not sent away) and without removing the engine number for rebore.

[Onne]

Well, that is not expensive at all! My sidevalve has cost over £1000 to rebuild

[brixtonmorris]

did the rebuild the engine for you onne?

[Onne]

yes. crank grind, head and block skimmed, 8 new valves, bigends new, main bearings, new +0.060 pistons with rings. and a new timing chain

[bmcecosse]

No need for leaded-bronze bearings in a Minor engine - unless you are super-charging it ! I know - I used to make the things ! Al/Sn will be fine - but if the bearings have been rattling for a while you will need a crank regrind - and often the grinders insist on supplying the bearing shells. To put new shells in a worn crank is just a waste of time and cash. And as said above - a new oil pump is a MUST - they are only £15.
Main reason Minor bearings fail - is low oil level. Be sure to keep it up to the mark and regular changes. crankshaft and bearings can be good for 100,000 miles if looked after properly.

[Onne]

but you do agree that bronze-lead bearings are better? Are they worth the extra? But all bearings like there oil.

[bmcecosse]

Leaded-bronze bearings do have greater load bearing capacity - and are therefore used in very high performance engines. But Al/Sn bearings are now capable of very high loadings and are used in all modern production cars. The crank should always be running on a wedge of oil inside the bearing - there should never ever be metal to metal contact. Hence running low on oil is absolute death to the crankshaft! And when starting a new engine - or one that has not run for a long time - the oil pressure should always be brought up on the starter motor (with plugs out) before attempting to start it.

[brixtonmorris]

did they rebuild the engine onne, not just machine it?

[wanderinstar]

You could give Brian Gostling a ring. I got a set of bigends and mains for £15 a set.
Ian.

[Onne]

They (well he) have completely rebuilt it (we're still in the process, waiting for some parts) I did help to take it apart though!

[bigginger]

We've got that interesting noise that tells us that we have a bigend problem. As the car lives on the street and we can't get it off road for repair it's off to the garage.

Just out of interest, you can do the big ends without taking the engine out of the car - I just have. Not sure I'd want to do that on the street though...

[Onne]

I don't think your back liked the gravel Andrew! But yes, it could be done, but how do you do the flywheel bit?

[bigginger]

You'd only need to play with the fly wheel to do the mains, the big ends are at the ends of the pistons and the main bearings between the crank and block. Unless I've been wrong about that all these years

[Onne]

I sort of mixed those up. Am I glad I am not rebuilding my engine!

[bigginger]

You should be - you wouldn't mix them up again