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MG MGF Technical - piston failure

My wife had just left home the other day and having done little more than 1 mile the engine made some noises and stopped.

The RAC thought the cam belt had failed and towed the car the local dealer.

The car is a 1997 VVC with approx 50k on the clock.

there had been no problems previously (other than the usual ignition lead replacements for poor starting) and there was no warning of the impending disaster.

The Local dealer has inspected the engine and told us that piston 1 had dissentegrated and damaged the bore and head.

They can find no obvious reason for the failure other than they believe the oil level was high (poss cooloing water in bottom of sump?) and that the head gasket may have failed and allowed coolant into the bore.

There seems to many threads in the BBS relating to head gasket problems, but there is no way the engine would have overheated after less than 1 mile at less than 30mph!

Any ideas ?
ken

I seem to recall that there have been cases where the liner has failed, and in those case MGR contributed to the repairs...

I don't remember hearing about pistons disintegrating, however.

Neil
(also 97VVC with 50+k miles)
Neil

Could it have been a cambelt failure leading to a smashed piston or a hydraulic lock caused by head gasket failure?

Not that knowing the problem would help at this stage.

Brian

Has it had the VVC cam bolt recall done?

- Andy
S6 AJG
Andy Gilhooley

Could be a cam bolt letting go(likley) and smashing a valve(s) into the piston/liner. Get some photos of the bits for a better analysis.Sounds £££'s :-( Any warranty?
Mike.
mike

Visited the dealer this morning to have a look at the engine.

Cam belt is intact and the cam bolt mod has been done.

Piston 1 is smashed and the top of both inlet valves are sitting on/in the piston. The cylinder liner is distorted and feels like it has a split or ridge in one side.

All of the other inlet valves are jammed down and there are slight imprints of these valves in the tops of the other pistons.

No sign of a fault in the head gasket.

There appears to be a piece of piston 1 missing (perhaps it failed from fatigue or metal defect?)

Rover have agreed to pay half of the bill because the engine has only had half of its expected life and it has been properly serviced by a rover dealer.

I think this is a fair solution and look forward to having the vehicle returned next week with a brand new engine.

Thanks to all who contributed advise.

Ken & Anne Jones
ken

This thread was discussed between 29/04/2002 and 03/05/2002

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