81280zx Posted January 4, 2007 Share Posted January 4, 2007 hey all i have a 81 280zx n/a and it smokes only when u hit the gas off idle and when floored and gives off a weird smell but at idle its ok and nothing and when cruzing nothing only when u need the power or its been sitting for a bit it will just when u take off but the rest of the time nothing. I was thinking maybe the valve stem seals are gone but wouldnt it smoke all the time then if they were shot? Let me know what u think thanks P.S. the smoke if white also Quote Link to comment Share on other sites More sharing options...
Careless Posted January 5, 2007 Share Posted January 5, 2007 hey all i have a 81 280zx n/a and it smokes only when u hit the gas off idle and when floored and gives off a weird smell but at idle its ok and nothing and when cruzing nothing only when u need the power or its been sitting for a bit it will just when u take off but the rest of the time nothing. I was thinking maybe the valve stem seals are gone but wouldnt it smoke all the time then if they were shot? Let me know what u think thanks P.S. the smoke if white also white smoke is most likely coolant. im going to assume that one of your coolant passages in your block has a small hairline crack in the headgasket. upon high revolution or extended periods of thrashing, it make weaken and twist enough to allow some of the compression that should be retained in the cylinder to divert itself into your coolant passage, and perhaps burn some coolant, as well as boil it to extreme temperatures due to excessive compression and heat entering the passages. have you checked the coolant in your rad? milky? rusty? chocolate swirl? be careful. your gasket could be on it's last leg. Quote Link to comment Share on other sites More sharing options...
81280zx Posted January 6, 2007 Author Share Posted January 6, 2007 the rad seems to be fine. It doesnt have coolent smell from the exhaust it smells like it is rich and its pushing out blk soot. If i drive it easy the car sees to be ok untill it gets to half thorttle and it starts its smelling and when its floored it smokes. The power seems to be decint for having 190k on it. but i have another z an 82 with 212k and it seems to have a better power band than this one to and its bone stock! Well i will consider changing the head gasket or just a total rebuild on it since i would be taking it mostly apart anyways. Thanks fo the comment keep them comming! Quote Link to comment Share on other sites More sharing options...
Guest TeamNissan Posted January 6, 2007 Share Posted January 6, 2007 white smoke is most likely coolant. im going to assume that one of your coolant passages in your block has a small hairline crack in the headgasket. upon high revolution or extended periods of thrashing, it make weaken and twist enough to allow some of the compression that should be retained in the cylinder to divert itself into your coolant passage, and perhaps burn some coolant, as well as boil it to extreme temperatures due to excessive compression and heat entering the passages. have you checked the coolant in your rad? milky? rusty? chocolate swirl? be careful. your gasket could be on it's last leg. You cant asume what it is until you know what color smoke it is...... Quote Link to comment Share on other sites More sharing options...
Xander Posted January 6, 2007 Share Posted January 6, 2007 hey all i have a 81 280zx n/a and it smokes only when u hit the gas off idle and when floored and gives off a weird smell but at idle its ok That's your tires dude. nothing wrong with your car Quote Link to comment Share on other sites More sharing options...
260pos Posted January 6, 2007 Share Posted January 6, 2007 Are you sure it’s white? White (steam), Blue (oil) Black (fuel). Personally my car does an impression of the country of Estonia’s flag, but he colors are what the colors are. You have to figure out what the source is. As it doesn’t do it at idle, get someone to follow you with a good nose. Most likely you are losing a head gasket. Do you get a lot of white smoke at start-up? Valve guides smoke generally at start-up too, rings smoke while decelerating, and an over-rich condition smokes when you have too much fuel. Quote Link to comment Share on other sites More sharing options...
Guest TeamNissan Posted January 6, 2007 Share Posted January 6, 2007 Are you sure it’s white? White (steam), Blue (oil) Black (fuel). Personally my car does an impression of the country of Estonia’s flag, but he colors are what the colors are. You have to figure out what the source is. As it doesn’t do it at idle, get someone to follow you with a good nose. Most likely you are losing a head gasket. Do you get a lot of white smoke at start-up? Valve guides smoke generally at start-up too, rings smoke while decelerating, and an over-rich condition smokes when you have too much fuel. I agree, oil can sometimes look white too but either way I vote head gasket. Quote Link to comment Share on other sites More sharing options...
81280zx Posted January 6, 2007 Author Share Posted January 6, 2007 i had a fellow z member follow me the other day and he said that it smells rich and it looks white but could be alittle blueish smoke no one that has followed me has said it smells like coolent i had a car that the gasket blew on it and it smelled like coolent and it had alot of smoke when it blew. when its cold it smells really bad and sometimes it will smoke just alittle at idle but goes away quickly. how do i check the valve seals to see if they are shot? Quote Link to comment Share on other sites More sharing options...
Guest TeamNissan Posted January 6, 2007 Share Posted January 6, 2007 A head gasket doesnt have to completely blow out for coolent/oil to leak in. Quote Link to comment Share on other sites More sharing options...
260pos Posted January 6, 2007 Share Posted January 6, 2007 How many miles are on it? it may be time to rebuild. to change the valve guides, you'll want to pull the head, "and while you're at it" steps in if you redo the head with a lot of miles on the bottom end, you will most likely begin to get excessive blow by at the rings. And more smoke! The year of the car means that you have one of the better block / head combos. Do what you can to save it, and good luck. Quote Link to comment Share on other sites More sharing options...
81280zx Posted January 6, 2007 Author Share Posted January 6, 2007 it has 190k on it now. i just took it for a drive and it is bluish for sure. but it has very good power on it. pulls hard from idle to redline but the smoke only comes on at about 2k rpms to like 3,500 rpms then goes away. unless im just going quick and cant see it. from what i see it happens only at high rpms if it is floored. i hope its not a head gasket cant afford to rebuild right now so i was hoping for just the valve seals. Quote Link to comment Share on other sites More sharing options...
81280zx Posted January 6, 2007 Author Share Posted January 6, 2007 i also wanted to put a turbo motor in but i cant find one here locally that is complete and has the ecu harness basically everything to make it run thats why i cant really afford to rebuild this one right now cause i want the turbo so im just trying to save it for now Quote Link to comment Share on other sites More sharing options...
260pos Posted January 6, 2007 Share Posted January 6, 2007 You may be able to change the stem seals if you pressurize the cylinders, but it would be a little spooky. Being if one of the valves dropped, you would most likely have to pull the head. I’m also not sure about compressing the valve springs from the top of the head. Maybe someone on the forum knows of a spring compressor designed for this application. Quote Link to comment Share on other sites More sharing options...
81280zx Posted January 6, 2007 Author Share Posted January 6, 2007 i have done the seals with a compressor to compress the cylinder so im not to worried cause i have the tools and valve spring compressor also. i was just woundering about what everyones opinion would be cause i need help trying to find it out but it could be the seals not the gasket. I guess i could get the seals from autozone for 22 bucks and try it out. Quote Link to comment Share on other sites More sharing options...
260pos Posted January 6, 2007 Share Posted January 6, 2007 Leaking stem seals generally only produce smoke at startup of after sitting at a light, it’s possible that you have more than one issue here. $22.00 and a valve cover gasket (+ liquid wrench; I prefer Beck’s myself) is pretty inexpensive. I’d give it a try as you have all of the tools at your disposal. Quote Link to comment Share on other sites More sharing options...
Guest TeamNissan Posted January 7, 2007 Share Posted January 7, 2007 If your saving for a swap anyway just relax and take it easy on the old girl. Quote Link to comment Share on other sites More sharing options...
81280zx Posted January 7, 2007 Author Share Posted January 7, 2007 yeah im going to take it easy untill my swap but i should just go ahead and change the valve seals soon just to see it doesnt hurt to try Quote Link to comment Share on other sites More sharing options...
Careless Posted January 7, 2007 Share Posted January 7, 2007 You cant asume what it is until you know what color smoke it is...... I guess you missed the big "P.S. the smoke is white also" in the first thread. LOL. I comment on the info i'm given, and nothing more. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.