by irlmin » Sat Dec 15, 2012 1:07 pm
Hi ,
We have done lots of work on this problem and solved most of the issues , the 'blasting' method has been used in the US with years and will work however it will not cure the problem alone , nor will the other method employed by some main dealers by removing the head at vast expense and having the deposits removed by a machine shop ,the problem is caused because the MINI is 'direct' fuel injection and whereas in older engines the fuel/ air mix was sprayed directly on top of the valve face in the combustion chamber and therefore offered the valve face a cleaning method , this is not the case in the MINI R56 engine as the 'charge' is under the valve . this combined with a very restrictive closed circuit breather system designed to keep any carbon in the engine and not out the exhaust has led to major carbon build-up on the valve heads , in fact when we looked into the combustion chamber with a borescope for the 1st time some years ago we were shocked we could not see the valve stem or head .anyway there are several ways to solve this , we use a chemical treatment to remove the deposits and have a breather modification which ensures the problem is resolved , we have used this method on many cars and all report a huge improvement in oil consumption some even not having to top up between service intervals .yes an oil catch tank will help BUT you will need to empty it occasionally and we feel the method we have used with success is the best way forward both operationally and cost wise . hope this helps .
G