Smoking Rover not the good kind

[eggman]

So here is my new problem. I have a 1971 series IIa that was given to me by my brother in law. It hadn't run in 34 years and I went over it and changed all rubber hoses/seals all fluids and turned it over with the hand crank to lubricate all parts and then started it. It ran rough but that was to be expected. Then I noticed that when it warmed up the rover smoked like a fiend (oil smoke). I took off the head thinking the valve guides might be bad and while out had the exhaust valve seats replaced with hardened seats (all of this was done by a business reccomended to me that has done rover work before aslo found out that it is a 8:1 as stamped on the head). I reinstalled the head and torqued the bolts as described. Started up the engine and initially had some black smoke and then took it for a ride around the neighborhood and by the time I got back the oil smoke was back and just as bad. Before dismantling the head for the rebuild the compression was 140's on all four cylinders (cold engine). I am stumped! Could the rings be bad and only showing problems when warmed up and should I test the compression after the engine has warmed up to see if they change? I pulled the oil pan and cleaned out the sludge in the pan and replaced the gasket and then used 20W-50 oil for high mileage vehicles. Believe me any and all advice is helpful. I have been working on this rover for a year and would like to get it in running and take my patient wife for a drive.

[Alk-3]

could it be running rich enough to blow smoke? how do the spark plugs look?
have you run it long enough to see if the oil level actually goes down?

[SafeAirOne]

Is it smoking all the time or just at certain times, like during engine braking?

Oh, and the compression checks shoud be done with engine at operating temperatures.

Is there a PCV system installed on this engine?

[LaneRover]

Is the smoke coming out the tail pipe or is it in the engine bay?

[eggman]

SafeAirOne, it is smoking all the time once the engine is warmed up, yes it has a PCV system and no I haven't changed the diaphragm, that is next on my list of things to buy, I have a weber carb coming to replace the zenith that was original to the vehicle, and I will post the compressions values later today. Lanerover, the smoke is coming out of the tail pipe. If I could upload the video from my iphone of the maiden drive I could give you the example of the smoking it is doing. I havent run it long enough to notice any oil loss I'm afraid the neighbors will run me out if i run it that long! Again thanks for all the help.

[eggman]

So here are the results and they are not good:
Compression cold - cylinder 1-120 2-125 3-120 4-95
Compression hot - cylinder 1-25 2-20 3-40 4-30

So obviously a problem but is it a head problem (just rebuilt) or a ring problem? If it is a head problem is there a way to check the head specificly? If there is then i can bring it back to the shop and get them to fix it. This sucks! Wondering if I just shouldn't pop for the RN head but I may need to still fix the rings! HELP!

[stomper]

wet compression test. add a teaspoon of oil into each cylinder and then recheck compression. if the numbers go up, it is the rings. if they stay the same, then it may be a valve issue.

My 1000 mile away guess? rings are toast. the oil has to be coming into the cylinder from somewhere, and it is most likely from the rings.

[Alk-3]

I agree with stomper. You can do a leak down test to figure out what the weak link is. I bet it's rings though, if you've just had the head rebuilt.

[LaneRover]

I agree on doing the leak down test - any chance the valves are too tight and need to be re-adjusted? Did you shave the head at all when you had the work done?

[Alk-3]

correct me if I'm wrong, but even if the valves were too tight and not closing all the way, that would create a low compression situation but it would not cause the smoking. the valve guides might, but they would have to be very bad indeed. If the head was rebuilt, I think it's very unlikely the guides are that bad.
I think the only real likely cause is bad rings, as lng as you trust your rebuilder that the guides were in fact replaced.

[Alk-3]

I had another thought.. can you start up the motor and then check the crank case breather pipe for blowby?
With compression that low, it should be significant, and shouldn't take too much to determine the rings are bad.

[eggman]

I will do the leak down test and let you know but I am heading out of town and won't be able to do it until I get back. Has anyone heard of checking the head by turning the removed head upside down then pouring a small amount of gas to see if it leaks past the valves or valve seals? Thoughts, smart or stupid? Lane I didnt shave the head and I don't know if the shop did but I can check the paperwork and talk to them. What would be the signs of a shaved head? Alk-3 I will check the breather then also because I will have to start it and get it up to operating temps to leak check the compression! Again thanks for all the help! What would we do without the internet? Oh yeah drink beers with friends and talk about rovers!

[Alk-3]

if you are going through the trouble of pulling the head again, I would just take it to a shop and have them check it out for you.
burning oil has not got a whole lot to do with a head though, generally, I don't think. it's possible the valve guides are leaking, but they would have to be leaking a lot to cause oil to be seen in the exhaust at the level you are describing. Also, with compression that low, I'd be willing to bet you are dealing with bad piston rings/wear on the bores etc.
if you pull the head, you can lap the vales to seat them, but again, I really doubt this is your problem.

[eggman]

so I finally got the time to do a leak test. here are the numbers:

compression cold 1/110 2/100 3/115 4/130
compression hot 1/50 2/72 3/50 4/45
compression hot with oil added 1/102 2/115 3/120 4/120

tell me if I did it wrong but I added the oil and then turned over the engine until the pressure gauge on the compression tester reached its maximum. This took maybe 20 rotations of the engine, basically ran the engine til the pressure no longer increased.

On a good note I replaced the Zenith carb with a new Weber and the rover runs great just some pesky black smoke when I goose the throttle. I plan on doing the ring job and I would like to change over to the electronic ignition but I am unsure of what I need. Any help with any aspect of the ring job or the ignition swap would be appreciated.

Thanks,
Dan

[eggman]

pulled the pistons after removing the ridge and here are the pictures, I need to know what everyone thinks, are they burnt out and require new pistons or are they normal and go with them. This is the first time I have done this so I dont know what a piston with
98K miles on it should look like.

Thanks