I have recently purchased a 1993 Jaguar Sovereign 4.0 on ebay. Seems a rather nice car but I do get a puff of blue smoke from the exhausts when I start from cold after it has been standing for a while. Should I be concerned or not?

 

Hi Matthew,

Congratulations on your "new" Jaguar! I owned a '93 for 16 years and it was a great car.

No cause for concern. The puff of blue smoke is normal behavior on an XJ40. The rubber valve stem seals harden and allow oil to seep down the valve stems into the combustion chambers overnight, where it burns off when you start the engine, leading to the puff of smoke from the exhaust. Most of the seepage occurs down the exhaust valve stems due to the tilt of the engine (which allows our Jags to have lower-sloping hoods).

Replacing the valve stem seals requires removal of the camshafts, and ideally, the cylinder head, so it's a big job. But the seals only last for a few years at most, so most of us just live with the puff of blue smoke.

Cheers,

Don

 

Thanks Don, that's very reassuring.

 

If mine didn't smoke on startup I would have to assume I was out of oil.

 

Me too!