998 copper lead main bearing shells

[814CWE]

1965 998 a series
replacement shells are white metal... but
these originals are a dark grey with copper showing through,,though crank is unmarked and the shells are not scored

same bl/bmc part number on 2 sets of shells
one set white metal..one lead bronze,,

are white metal mains ok on a 998 cooper bottom end??

[ivor badger]

1965 998 a series

these originals are a dark grey with copper showing through,

Then they are knackered.

[814CWE]

i assumed so,,but with a micrometer theres no wear present,,

dont worry im not reusing them

[66S]

originals are a dark grey with copper showing through,,though crank is unmarked and the shells are not scored ??

Copper is the wearing surface, the lead skin is thin and only used as a seating agent. Bearing shells that are showing copper are not stuffed at all and can be reused if it is determined bearing clearances are within acceptable tolerance. Many shells are thrown away for no good reason.

Al

[Vegard]

originals are a dark grey with copper showing through,,though crank is unmarked and the shells are not scored ??

Copper is the wearing surface, the lead skin is thin and only used as a seating agent. Bearing shells that are showing copper are not stuffed at all and can be reused if it is determined bearing clearances are within acceptable tolerance. Many shells are thrown away for no good reason.

Al

I do indeed agree. Measure them, and if they are not scored, why not reuse?

[andy1071]

I would have thought that the copper is there to bond the 'white metal' to the steel backing, as they both bond well to copper, but not to each other.

[ivor badger]

I would have thought that the copper is there to bond the 'white metal' to the steel backing, as they both bond well to copper, but not to each other.

That is exactly the point. Whatever thickness the lead indium, it means the shell has worn at least that amount to show the copper.

You never reuse shells, regardless of how good they look. They never reseat exactly and they are garunteed to score the crank.

[Vegard]

I would have thought that the copper is there to bond the 'white metal' to the steel backing, as they both bond well to copper, but not to each other.

That is exactly the point. Whatever thickness the lead indium, it means the shell has worn at least that amount to show the copper.

You never reuse shells, regardless of how good they look. They never reseat exactly and they are garunteed to score the crank.

I'm not cheap when it comes to engine parts, but I guess we have to agree on disagreeing on this..

[66S]

Me too Vegard.

Al

[814CWE]

well,after being in the motor trade many years,never heard of not re-using the original shells cos they will score and run incorrectly..
only way they will fail is incorrect assembly or dirty assembly
they are already mated to the crank pins,so shouldnt be an issue.

i fitted replacement shells ,but a double check with a micrometer showed the original vp shells (showing copper) to be actually slightly better on tolerance than the new replacements,,

pffft,,
so much for buying new stuff eh??

[ivor badger]

well,after being in the motor trade many years,never heard of not re-using the original shells cos they will score and run incorrectly..

Well after many years in the motor trade, I found out very early on.

Anyway, it's a 998, why would it need super expensive shells unless you are vgoing to race it.

[814CWE]

was only saying a point that the old vandervell shells are a much better tolerance than the newer stuff readily available

[ivor badger]

was only saying a point that the old vandervell shells are a much better tolerance than the newer stuff readily available

That's without doubt. Even the guys who worked in Glacier bearings Kilmarnock went and bought Vandervell shells when rebuilding their engines

[Ronnie]

Just to promote the argument - discussion! >>> http://www.waukbearing.com/Files/Knowle ... arings.pdf

Please continue.

[814CWE]

was only saying a point that the old vandervell shells are a much better tolerance than the newer stuff readily available

That's without doubt. Even the guys who worked in Glacier bearings Kilmarnock went and bought Vandervell shells when rebuilding their engines

i love it!!!!!!!!


vandervell shells or not,depends what brummy built your particular engine too at bmc
some die at 40k miles and some happily go round the clock,,,,regardless of service intervals..

as we say nowadays,,mass produced crap