93 SOHC smoking! Valves or Rings?? DOHC block the same?

GringoEJS · Post by **GringoEJS** » September 5th, 2005, 5:40 pm

I just picked up a 93 MX-3 with the 4 cylinder for cheap because of how badly it smokes. When you crank it up, it really doesn't appear noticeable, but once you start driving or revving it, it smokes like a b*tch. Whitish smoke that billow out and lingers. When I drive around the block, just keeps smoking, more smoke at higher RPMs. Tends to decrease a little when the engine is warm. I checked compression and its 150 in all 4 cylinders. The oil has no coolant and the coolant has no oil. I can see where the headgasket was replaced fairly recently which indicates it was probably overheated at some point. I bought a DOHC engine not realizing that the 93 and 94 had different engines. So, could I still use the DOHC block if my problem is rings? If my problem is valve seals I need to return the DOHC motor.
So, can someone tell me for sure what the problem most likely is? And if there are any more clues I should provide, please ask.
Thanks

95 rs · Post by **95 rs** » September 5th, 2005, 5:50 pm

im pretty sure that it isnt the rings because you would have like a dark bluish blackish smoke from the oil burning and i believe that the white smoke would be from coolant burning so it is possible that the person who did the headgasket didnt do it properly. and the blocks are not the same i believe but dont quote me on that. but im 75 % sure its not your rings.

Gro Harlem · Post by **Gro Harlem** » September 5th, 2005, 6:31 pm

block is different.....the dohc has a 2-peice block

Tunes67 · Post by **Tunes67** » September 6th, 2005, 12:37 pm

Having just had a very similar problem with the engine in my B2000 truck.. I can say that if its smoking continuously.. its probably your oil control rings. I had tons of white smoke with a slight bluish tint coming out from my engine.. I just did a ring job on the engine this past weekend and found that all 4 sets of oil control rings were badly worn and 1 set was actually seized to the piston. I am also replacing the valve seals on the head as well.. but while I did find a couple of valve seals that were hardened and not doing their job.. that amount of smoke would have had to have been coming from the rings.

Having said that.. Coolant will also show as white smoke or steam out the tail pipe.. so it could still be a blown head gasket or maybe someone used the wrong head gasket.. but this would be easy to tell because your coolant level would drop every time you ran the engine.

Hope this helps

Tunes67

GringoEJS · Post by **GringoEJS** » September 8th, 2005, 3:13 pm

Well, I am still a little unsure whether it is the HG or rings, but I am leaning towards rings. Coolant doesn't seem to be disappearing, and I did an oil change and used 20W-50, Lucas Oil Stabalizer, and Smoke Be Gone, and although it still smokes, it doesn't blanket the neighborhood anymore. I guess I need to go find another block...

Shades · Post by **Shades** » September 10th, 2005, 10:03 am

If you pull the head to do either the rings or seals, do them both while everything is apart... saves time and money pulling it apart twice.