blue smoke 75 280z

hi, i'm hoping i can get some good advice here. i recently picked up a 75 280z which had not been used since 92. i was told that the transmission had been rebuilt about 4 years ago. it also looks like some engine work has been done, the head gaskets look fairly new. the car was basically in pretty good shape. no rust or dents. i did relpace all the injectors, plugs, fuel pump, filters, master brake cylinder and some other misc. parts. the car started up and was running real nice for about 1 week then it started hesitating, stalling and i noticed blue smoke out of the exhaust. when i tried to start it, it sounded like it was flooded. i pulled all the plugs and noticed heavy black soot. sandblasted them, reinstalled and it started right up. runs lousy, quite a bit of blue smoke, heavy hesitation and does stall out after about 5 minutes of idling. please keep in mind...i am not a car mechanic, just a plumber. i enjoy working on my cars so i try and do it all myself. any help would be greatly appreciated, thanks in advance

hi, i'm hoping i can get some good advice here. i recently picked up a 75 280z which had not been used since 92. i was told that the transmission had been rebuilt about 4 years ago. it also looks like some engine work has been done, the head gaskets look fairly new. the car was basically in pretty good shape. no rust or dents. i did relpace all the injectors, plugs, fuel pump, filters, master brake cylinder and some other misc. parts. the car started up and was running real nice for about 1 week then it started hesitating, stalling and i noticed blue smoke out of the exhaust. when i tried to start it, it sounded like it was flooded. i pulled all the plugs and noticed heavy black soot. sandblasted them, reinstalled and it started right up. runs lousy, quite a bit of blue smoke, heavy hesitation and does stall out after about 5 minutes of idling. please keep in mind...i am not a car mechanic, just a plumber. i enjoy working on my cars so i try and do it all myself. any help would be greatly appreciated, thanks in advance

well your definitely burning oil and are you sure its a 280zx. im runnign short in time so i will finish my post later or someone else can get to it.

not a 280zx, a 280z, not being a smart ass just not sure it that'll make some kind of difference

hmm, have you ever heard of a product called seafoam? it's supposed to clean out all the carbon and crap that's compounded in the engine, which it's sounds like it has done.. if you take your intake plenum off, i'm sure you'll find that it's covered in all sorts of black crap caked onto the inside of it.. some throttle body cleaner/brakeleen should clean that right up.. i'm sure there's other products running around, but i think the official name of the stuff is 'combustion chamber cleaner' or something like that.. anyway, that's my input

not a 280zx, a 280z, not being a smart ass just not sure it that'll make some kind of difference

sorry im not too familiar with my older Past Z Cars...i was under the impression that the 280'swasnt offered until later years. sorry...i wasnt sure, thats why i asked you.

anyways, its sounds like maybe your piston rings are fried...something definitely isnt sealing the oil where it should be. the first thing that pops in my head is piston rings...

thank you very much for the advise. i will try some of the cleaners you suggested and if all fails...i'll get my datsun repair manual and try the rigs as you mentioned. one more quick ?. is it possible for a bad pcv valve or "a timing" issue to cause this?

thank you very much for the advise. i will try some of the cleaners you suggested and if all fails...i'll get my datsun repair manual and try the rigs as you mentioned. one more quick ?. is it possible for a bad pcv valve or "a timing" issue to cause this?

no you shouldnt be burning oil due to those reasons.

you have a more serious problem...you are leaking oil into your combustion chamber which means that your burning that oil causing the blue smoke that you see. this is a prime example of piston rings that arent sealing properly. of course it could be some other things...before you go tearing your engine apart i would get it to a mechanic and have him see for sure. piston rings are just something you open up your manual and put a wrench on...you literally have to tear the whole engine down.

thanks to all who relpied. i will definitely have a mechanic look at it before i try and tear into it