Knackered shells - Advice please!

[driftin jo]

Would you have the same problem going from Fully synthetic to semi synthetic and vice versa or does this only occure when going from mineral to any synthetic?

I'm not and expert on this subject and only know what I was told a good few years ago and what I have googled today about it .
As far as I can work out the main scenario for concern is an engine that has done a lot of miles on mineral oil then is changed to running synthetic oil . There may well be other scenarios that would cause this sort of thing but I'm not sure.

[oilman]

Its not really an issue, it can be an issue if the engine has been poorly maintained, and very poor quality oil used and rarely changed, however if the oil is of any worth then it will break the old crud down and hold it in suspension. Filters, these days are essentially bolt stoppers and the crud held in suspension should flow straight through the filter and will be removed at next oil change. We advise you stay away from flushes, these CAN do more harm then good by "over cleaning" the engine, some deposits are better off left where they are and then what is left of the flush just mess with fresh oil.

For the OP, the Vaux/GM stuff is mineral base (despite being sold as a synthetic) so I very much doubt that the issue is synthetic vs mineral if you have been using semi synthetic previously (100% mineral base).

Cheers

Guy.

[madpugger]

Thanks oilman.

What the hell caused it then?!

[oilman]

Not sure, how much power are you producing?

[madpugger]

Not sure, how much power are you producing?

Around 280. It had fresh oil and filters after around 15 to 30 mins running after the rebuild. Number one shells totally gone. Number 2 scored a little but not checked the rest yet.

It didn't get much of a running in, but running in really only applies to bores after honing and ring which it didn't get. The big end effectively runs on the oil with no metal on metal contact

I'd forgotten it happened to Ross too.

[Error404]

did it spin a bearing? Did you clearance them with plastiguage or the like?