The vehicle -- '89 Raider 3.0L, 225,000 miles on the odometer, bone stock, heads have never been done as far as I know. In the last 3 years the intake manifold gaskets, valve stem seals, HLAs, timing belt and water pump have all been replaced.

The Raider is starting to have an issue with smoke from the exhaust. At first, I noticed it only on cold start, but now I'm noticing it after warm start up as well.

I thought it might be a slightly breached head gasket because I am slowly losing coolant (as in the overflow tank goes down in about a 1 to 1.5 weeks), but no sign of coolant in the oil, or vice versa. I'm detecting some signs of the radiator cap leaking so this might explain the coolant loss.

Operating under the assumption that it might be a head gasket, I ran a compression test yesterday (plugs out, engine warm, cranked for 7 times each cylinder, but I did not hold the throttle open) with the following results:

1 -- ~180 psi
2 -- ~180 psi
3 -- ~175 psi
4 -- ~180 psi
5 -- ~180 psi
6 -- ~180 psi

The only value I can find for compression is the limit value of 119 psi. Are the above decent values, or are they on the high end (which apparently would mean the combustion chambers are carbon-caked and the heads need to be cleaned)? I didn't re-take compression readings "wet", because these seemed pretty decent to me.

What would y'all recommend I look at next? The plugs are relatively new and looked OK to my admittedly un-trained eye. I would have thought there would be a wider variation on the compression readings if there was an issue with a dropped valve guide or something. Is it possible the valve stem seals have failed in this time frame/mileage (2-3 years, maybe 20K miles, I don't have my records handy right now)?

Really not wanting to drive it much with the smoke screen it is laying down... <img src="/forums/images/graemlins/baby.gif" alt="" />

Any insights and suggestions would be appreciated!

Eric W.