Need help from ford tech's please.

[fuzzypuppy]

I don't have a ford really but a mazda though from what I understand the ford 2.0 and the mazda 2.0 are one and the same which is why I'm posting here plus I tried posting in the mazda section but got zero answers.
Not being familure with either ford or mazda 4 cyl engine design, I have a question or 2 about the head design in particular, 2.0 head design to be exact.
With the valve cover off and just looking at things it looks like the way these are set up is that instead of running the valve's directly to the cam or useing a rocker these heads are set up with running a hydrolic type lifter off the cam directly then below these lifters is the valve, is this correct?
I ask this because I got this 93 626 basicly for free, the guy who owned it said it was smoking like crazy with valve train noise, though it still ran ok.
I'm pretty well versed in v8's and 6's of all make auto's and in my experience in these engines bad valves could not account for alot of exhaust smoke, the guide's and seals would have to be so bad for this that the engine simply would not run at all.
Now in looking at this ford/mazda head design it would seem that there must be some sort of seal around the lifters to prevent oil from passing around them down into the cylinders, is this the case? is it common for these seals to fail?
The engine has 175.000 on it which is kind of high but not that high.
The other thing that could account for alot of smoke would be rings but if it ran as well as the guy said it did I doubt this is the case.
Other than this if there is anything else you guys can tell me about these engines like common problems or tips I would really appreciate it.
Though very filthy the car is pretty nice and after being without a car for quite awhile now my wife can't wait to get it going.
I was also wondering what I can expect as far as mpg and performance with this engine.
Thank you ahead for any input.

[rhandwor]

Check compression if it is low squirt oil into the sparkplug hole if it comes up it is rings. The cost of the these lifters I would check on getting an engine imported from Japan. I've had good luck using these engines. Save your engine as these have different intakes. I installed new seals as it is much easier with the engine out. I've also taken them to a machine shop and rebuilt them. Price a rebuild and a good used engine. You might try a valve job. Also valve seals can be changed. I've replaced the lifters but it was over 10 years ago but I don't remember any problems leaking oil just not working. I checked compression and changed lifters on the bad cylinder.