Crank Case Compression

[mickeytwonames]

I seem to have a case of 'Crank Case Compression'. This seems to be the cause of my previous thread 'Texas Tea' about oil smoke coming from the breather tube on the rocker cover. It's been darkly hinted that it is 'yer piston rings.'
Dose anyone have experience or advice of this 'Gold Seal Syndrome'?

[bmcecosse]

Have you carried out the test - with hot engine, oil filler cap removed -and revved up? If there is a plume of smoke/fume - then yes indeed the rings/pistons/bores are worn or damaged.....

[mickeytwonames]

Yes - they're worn on number 4 cylinder. is there any big danger in short journeys till i can sort the problem out?

[mickeytwonames]

Is it an engine out job?

[bmcecosse]

How do you know it's #4 cylinder? No 'big danger' but oil consumption will be heavy.... You can pop out the pistons with the engine in place - take the head and sump off.

[mickeytwonames]

I replaced the head gasket thinking my problem lay there - it didn't but other issues were fixed and all gaskets changed etc.
I've got time on a ramp - I'm going to replace the shells and rings. Everything is OK above the sump - is there anything else I can usefully do with the crank case off?
Also - Best Practice - do you do one cylinder at a time or go for all four.
Lastly - Do you need to run piston rings in?
Again, many thanks for your support

[mickeytwonames]

And, Blimey
Bull motif sell:-
948cc Piston Ring Set(standard)
948cc Piston Ring Set(+20)
948cc Piston Ring Set(+30)
948cc Piston Ring Set(+40)

Which do i need?
When I had the head off (I think) I remember the letter 3 stamped on the block

[bmcecosse]

You need to see the tops of the pistons - they will be marked STD or 010 or 020 etc to indicate size.. same with big-end shells - you need to see the back of the old shells to see what marking they carry... You would do all 4 pistons at the same time... The bores should be 'glaze busted' - and yes you would take it easy on new rings first few miles... You should understand - new rings in old/worn bores are not going to make a huge difference - and any improvement won't last long. But if you only do a v limited mileage - that could be a few years, and may be what you are happy with.

[mickeytwonames]

Many thanks - what is glaze busted?
The pots look clean and are not scoured and there is no piston movement/wobble - it that just an illusion to their wear?

[JOWETTJAVELIN]

The bores need checking by a professional for ovality, amongst other things. If they are ok then indeed deglaze and a set of Cords if you can get hold of them.

Tbh, you're getting into full-blown rebuild territory here, or at least might as well do.