XK-8 oil consumption

(Dale Warrington) #1

Am I the only one to have oil consumption problems? My 2003, 4.2L, XK8 emits a huge oil smoke cloud after driving, then sitting (not running) for 30 minutes or so, and then re-starting. Not so much on cold starts in the AM. I thought it might be valve stem seals, but apparently no one else has this problem. Just purchased the car, so I don’t know anything about th engine except that is not the original. Any ideas?

(JLo) #2

Hi dale, mine emits smoke when starting it sat for more than 30 mins. It burns about 1 quart every 500 miles. But then, my 97 xk8 does have nearly 230k miles.

(Paul Wigton) #3

Likely bad valve stem seals: easy way to tell: smokes on hard acceleration= rings, smokes on overrun (foot off loud pedal, rolling down in speed) = valve seals.

(Dale Warrington) #4

That’s what I thought, but it doesn’t seem to be a common problem like it was on the old small block Chevys. No other references on the forum.

(Dale Warrington) #5

Removed the left cam cover, and the way the head is designed, valve stem seals seem to be less likely the culprit. Plugs do show signs of oil burning. Back hurts, so I will run a compression check Monday.

(Paul Wigton) #6

A leakdown test would be called for, too.

(Dale Warrington) #7

I have only had my XK* for about 6 weeks now, and it has been in my shop getting new paint, shocks, spring isolators, upholstry, and a few other small repairs. Consequently, I have only driven it about 60 miles. Thought I had a valve seal problem, but now have decided that I have a coolant leak problem. After running the car a few miles and getting pressure on the cooling system, I get smoke out of the tail pipes on re-start. Smells like anti-freeze more than oil. Today, I ran it for about 30 minutes, shut it off for a few hours, re-started it and got a huge smoke cloud. Shut it off again ,loosened the coolant cap, let it sit for about 30 minutes, an NO smoke. Being that there is no coolant flow through the intake manifold, I am asking for any suggestions as to where to go with this.

(Eric Capron) #8


Are you actually loosing coolant? If so, I would get the cooling system pressure tested because if you’re correct and coolant is getting into the exhaust I’m wondering if you have a head gasket problem.

Shropshire, UK

(David Julian Price) #9

It does sound like valve stem seals. If I were you I would change the oil for a slightly thicker type than you’re using, and add an additive like Forte Seal Conditioner. This has done the trick with several of my Jags over the years. The worst thing you can do is drive around on old oil, which may be harming the rubber seals.

(j limongelli) #10

Well its an 03?
They had issues with LEAK DOWN if the car was pulled out from the garage then pulled back in without a heat cycle.
They used to load up.
Could be a combo because of your PLASTIC thermostat housing as well, let me explain.
If your thermostat housing got stuck and cracked as they did, you could have overheated the car.
Hence the head gasket that you don’t know about yet…
Next if the car was always moved around but never driven the plugs would load up as the fuel cycle loop didn’t close fast enough or DRIBBLE in the cylinder.
These are two VERY common issues with THAT v8.
Look to see if the plastic thermostat housing was replaced.
That would mask the issue till you bought it.
Second check your dip stick, it will tell the whole story.
Good luck

(Dale Warrington) #11

Thanks, but actually turned out to be the CCVent valve.

(j limongelli) #12

Well that’s great to hear

Never heard of losing water and oil over it but hey…
Enjoy the ride!

(Dale Warrington) #13

Never lost any water. Thought it smelled like antifreeze burning, but must have been the synthetic oil.