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Discussion Starter #1
Read an article recently, in a Motor magazine, where the subscriber asked if it was necessary to remove the wear ridge at the top of the cylinder before fitting new piston rings. Anyway the reply more or less indicated that with modern engines, fine tolerances, gasket precision and so forth, it was perhaps not advisable to deploy that ridge remover.

And there was myself being instructed years past, that the ridge was removed with that Tungsten bladed precision cutter, on the basis that the new rings could hit the ridge and fracture/crack. Top compression I'm referring to. Always cut that ridge away before fitting PEP replacement pistons, and /or oil control rings in the past.:rolleyes:

How ideas, methods change over time, I guess piston and ring replacement is so infrequent nowadays, and re-boring only done by a few? New short motor Sir? That'll be a second mortgage required :eek: !! :D :lol:
 

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We used to remove the ridge on motorbikes when we fitted new rings, otherwise they might break if they hit it. That coupled with a light hone to give the rings something to bed in against.

TBH I haven't seen much of a ridge on car engines they I have looked at recently, even on big mileage cars. Although you do sometimes get a ring of carbon deposit.

I think Modern oils just don't allow as much wear to take place on bores as in the old days.
 
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^ what symonh2000 said.

It's true that bores seem to last for longer and honing marks are often still visible long after you might have expected.

However I cannot see how a wear ridge can be other than somewhat rounded on the internal corner and wouldn't want to risk new rings running up against one.

Moreover, if the bores are worn enough to have a noticeable ridge, then honing marks are long gone. What's going to retain oil while the new rings bed in? How will the bore be honed in the vicinity of the ridge?

Time for at least ridge removal or rebore/new liners I'd say. Not done this for some years though - anybody have completely up-to-date experience of this?
 
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Bore wear definitely isn't the problem it used to be. 100000 miles used to be the limit for engines. By then the bores would be absolutely shot. There were quite a few quick remedies around though. Pep pistons that ZF mentioned, there were cords rings, multi piece rings to take up the groove wear. Some of the ring sets had a stepped top ring to miss the wear ridge, ridge dogers we called them.
Do you remember them ZF?
 

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Discussion Starter #5
Yep! the stepped top rings came with oilmasters and similar,iirc? Just wondered if something like this might be a deciding factor in the problem a number of AO'ers have had, with oil consumption? just a thought?

And possibly the lack of wear ridges may be down to various factors, better lubricants, materials in block/cylinder construction, plus...more piston/ring to bore tolerances? Twinny using oil, set of oilmasters Sir? if you can still get them? Or how's about a set of Chords?:D:lol:
 

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Alfa wouldn't bother with replacement rings to control oil consumption.

Instead they recommend a thick oil, that won't get past the rings as easily. :rolleyes:
 
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