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Hi all

Recently I've had some over heating problems on my 56 plate 3.0SI Coupe. It's been diagnosed as a water pump problem which has now been replaced. They suggested that I have the thermostat replaced at the same time. However, they had difficulty finding a match. Apparently the one on the car, which I guess is the original, is metal whilst the replacement (they've tried two, including one from BMW) are plastic. Not a problem in itself but the lugs don't line up and it would mean possibly damaging the pipes to fit it.

Currently, the car seems to be running OK with just the pump replaced but it's a bit worrying if the thermostat does fail in the future.

Has anyone come across this? Is there a fix?

I wouldn't worry about it. I've never known a stat to fail on the N52 - looks to be a very high quality item.

I recently replaced a thermostat on a 3.0si and had this very issue... original was metal new one was plastic!

The pipes you'll be struggling with are the ones with spring clips I'm assuming, one large and one small! The lugs on the pipes lined up fine but couldn't get it to seat far enough in so refitting the retaining springs was a problem! The small pipe went on with a dab of washing up liquid and brut force... the larger one has an o-ring and a spacer in the pipe opening, by ditching the spacer but keeping the o-ring and the same washing up liquid and brut force approach it went in just fine!

I think the plastic ones a slightly different design to the metal and have the spacer incorporated!?

But as ph001 has pointed out I think you'll be fine as the thermostat hadn't failed, they are electrically operated so don't fail like the traditional type do!

Thanks for the answers. Reassuring to know that I wasn't the only one and also that I should be alright.

Cheers!!