My 805R wagon decided to toss a valve just recently. I have owned this car since new and have maintained it like a baby.(Changed the diapers and anytime it screamed-I fixed the problem)I do drive my vehicles pretty hard but since it is an auto-no overrevving or abuse. No aftermarket parts. Is this something that is typical for the 850R's? Or perhaps 850's in general? It has been maintained by a very reputable Volvo dealer but they will of course not admit to any general problem. I am not complaining about their service-it has been top notch-but this appears to be a manufacturing problem.

Cheers,

I had a problem with two burned exhaust valves at 51K miles (on the same cylinder). Dealer mechanic had no clue as to why it happened--there was a small chip on the rim of one of the valves. Non dealer mechanic said he had seen the problem now and then and thought it might be caused by breaking insulator on Bosch platinum plugs. I had put same plugs plugs in about 15K miles prior to this problem. Needless to say, I don't use platinum plugs any more....

A burned valve is not common but it's also not unheard of either.
It's more likely to occur on an engine that IS baby'd too much (low rpms) as it occurs because the valves don't turn enough (yes, valves spin) and consistant low RPMs with poor quality oil can cause a valve to burn, usually intake valve.
When you have it repaired (just the burned valve IMO), switch to a good synthetic oil (Mobil 1 or better) and don't be afraid to drive it with higher RPMs.
The early 960s would actually run rough due to a Valve related problem (before they'd burn) and Volvos cure was to change oil using Mobil 1 and give the car "an italian tune-up" which means a high spirited, high RPM test drive. That cured the problem.

Thanks for the reply.
I have used Mobil 1 since 16k miles and I do drive the car pretty hard when I drive it. What I meant with "babying" it was that I have done all the required maintenance and never skipped an oilchange or filter replacement. It is a bit disappointing that it would happen but ,like everything mechanical, you never really know when it will break. In this case it was the exhaust valve that went.
To Volvo's credit the car took us home on 4 cylinders for 150 miles. It ran a bit rough and with very little power but I could manage 65-70mph. I disconnected the injector for the affected cylinder so I wouldn't burn up the catalytic converter.

Cheers,

Valves get burned now and then on all engines out there, Volvo has no manufacturing problem with the white engine, in fact it's the most bullet proof part in the car. I'd recommend putting a rebuilt head on the car when you make the repair.
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Rich K. http://www.volvospeed.com/bay13.htm bay13@cox.net

Thanks for your reply.
That's exactly what I am doing and then the car will be for sale. Funny thing is I have a new R on order, it's almost as if the old car knew.....

Cheers,

I had this happen on my 96 855 turbo 120,000 miles ago at 49,000 miles. Fortunately, warranty took care of it. The Volvo Master Mechanic at my dealer explained that Volvo had a documented problem with burned valves occurring from a very small leak in the exhaust manifold gasket letting a small air leak hitting the exhaust valve and causing premature failure of the valve. Something to consider...

Larry U.

Also being a dealer master/expert tech for years, I've never seen any such documentation from Volvo that says "an exhaust air leak burns valves". I highly doubt that story nor does it make sense as air can't go backworks in a pressurized exhaust system (engine running), it's impossible.