"Enrico,

In reply to Anders' question re Merak engine durability:

I’ve owned my Merak SS all of 3 months now, but I’ve known the car since 1999 as it belonged to a good friend. It has covered 79,000 km and I very much hope will go to 100,000 and beyond. At the level of mileage I’m likely to do that’s about another 9 years. We’ll see which lasts longer - the car or me!

I’m not an engineer or mechanic, but these bits of information I’ve gathered from the experts along the way:

The Merak engine was a development from the SM engine, which was very much a Maserati engine rather than a Citroen engine. It in turn derived from an abandoned V6 racing engine project. Now, racing engines, as we know, are designed for maximum performance rather than longevity, so perhaps there is some inherent weakness in the design? Compare with the Biturbo engine (which contrary to what some say is not a derivative of the Merak engine); this is an extremely strong engine, designed to cope with the stresses imposed by two turbochargers, and after all, De Tomaso was going for the mass market approach when he introduced the Biturbo. Presumably, he didn't want anything with too volatile a characteristic. Indeed it seems that most Biturbos have faded away through rot, neglect, and other mechanical problems rather than basic engine failure.

Anyway back to Meraks.

Perhaps the main weakness in the SM engine is the potential for failure of the sodium filled valves. The valve stems are fairly thin, as well as being hollow, and particularly in a situation where there is internal engine corrosion, they can break with catastrophic results for the engine. It seems that all the SM engines had these hollow valves, so if you have an SM you know what the danger is. The early Meraks all (we think) had hollow valves, but by the time the SS arrived some were built with hollow valves, some with solid. As is often the case with Maserati there seems to be no record of which engines had which valves fitted, so the only way to find out is to open up and have a look, which of course is an expensive option on these cars unless you are able to do the work yourself.

Until recently it was thought that none of the SSs engines had failed due to hollow valve failure; however there have been two cases recently; I don’t know the full situation but in one of them I believe it was a very low mileage car where the engine had stood unused for long periods of time and had suffered internal engine corrosion.

For my own car I may well have the valves looked at and replaced if necessary when I next have mechanical work done on the car; in the meantime it’s a case of treating the engine with respect and not overstressing it – which is what we should all be doing with classic and older cars, although of course its all too tempting to go faster and rev harder in Italian exotica! It is prudent to allow the Merak engine plenty of time to warm up completely; it can take 10 miles or so for the oil temperature to come up to normal; try to keep the revs at 2500 to 3000 during this period, and below 4000 afterwards – that’s the regime I follow. Oil must of course be changed at the proper intervals and care taken to top up when needed – these engines do consume a moderate amount of oil (or leak it out!). And use the correct oil - the brand’s not too important, but it has to be a fully synthetic of the right grade. I’ve seen a semi-synthetic being sold for Meraks – does anyone have any views on that?

Interestingly there is a Merak that goes racing; I wonder what the situation is with that engine?

Of course any engine can be made to fail quite easily by ignorance, neglect or mistreatment. Jeremy Clarkson proved that in a deliberate way when he trashed the engine of a poorly maintained Merak on Top Gear; I’m sure he could have done likewise in a Mondeo if he had tried just a little harder!

Hope this helps and here’s to many happy miles or kilometres of trouble free motoring in our Meraks.

Best regards,

Roger."