justinr54321 Posted June 3, 2007 Share Posted June 3, 2007 Well, I just bought my 1972 240 Z about 3 weeks ago now, and I've been tuning the carbs and engine out to where it won't sputter (it was sputtering about 3500 rpm's). I got that to stop, however, I'm now getting a popping sound with white smoke from the exhaust. Any ideas of what it could be? Any help is appreciated, and I live in Lynnwood, WA if anyone is able to come over and help me finish tuning this thing out. Thank you. Quote Link to comment Share on other sites More sharing options...
MatMan Posted June 3, 2007 Share Posted June 3, 2007 Congratulations and WELCOME! Sounds to me like you are a bit too lean. Is the popping when you decelerate, or when you are standing still? Is the white smoke really bad, or just whispy? Do you have the Z Therapy Just SU video? It's a bit dry, but a TREASURETROVE Of SU carb knowledge. Good troubleshooting advice, as well. Quote Link to comment Share on other sites More sharing options...
justinr54321 Posted June 3, 2007 Author Share Posted June 3, 2007 Congratulations and WELCOME! Sounds to me like you are a bit too lean. Is the popping when you decelerate, or when you are standing still? Is the white smoke really bad, or just whispy? Do you have the Z Therapy Just SU video? It's a bit dry, but a TREASURETROVE Of SU carb knowledge. Good troubleshooting advice, as well. Thanks Mat. Well, the popping is while standing still and accelerating and decelerating, almost like my air pump might be bad, I don't have a pressure guage to see if it is or not. And the white smoke is really bad, all the way through all the rev's, after she warms up. And where do I find this video? Definately would be helpful in getting the engine tuned up while I get the body work done. Quote Link to comment Share on other sites More sharing options...
jdarkme Posted June 3, 2007 Share Posted June 3, 2007 They sell the video here: http://www.ztherapy.com/ Quote Link to comment Share on other sites More sharing options...
justinr54321 Posted June 3, 2007 Author Share Posted June 3, 2007 Also, does anyone know whereI can find a diagram for the vacuum lines? I just want to make sure they are connected right. Thanks. Quote Link to comment Share on other sites More sharing options...
justinr54321 Posted June 4, 2007 Author Share Posted June 4, 2007 Ok, question, for I do not know if this is true or not. Is it possible that my Z might not be burning all the octane which is causing the white smoke? For after I did the oil change, I put Lucas fuel system cleaner in the tank with a fill up of Chevron with Techron premium gas, (91 octane rating). When I first start it, there are little puffs of white smoke that is barely noticable, and gets worsst when it warms up. I tried using a lot of carb and choke cleaner today, and didn't do any difference on the smoke, however, I did have to re-tune the idle settings and the carb balance was off, so I fixed that today too. (Found this out after I took off the whole air filter assembly). Now, when it idles up, idles up fine, until about 5,000 rpm's, then bogs down to 4,000, until I take my foot off the gas a little, then idles back up just fine. Now, when decelerating, I am getting a machanical popping sound. Is my idle settings still off a little bit? I'm about to take it in to Z Sport on Tuesday and I might have them adjust the carbs for me, if they don't need rebuilt, then I will do that myself, and then take it in to them. I do wish there was someone who could came and give me a hand a little bit, but oh well, its all the more fun figuring most of this stuff out for myself. Thanks everyone. Also, I can't find the air/fuel adjustment screws on these carbs. Can someone please post a picture of where they are located? The car was made in 2/72 (according to the label on the door fram on the driver's side). Quote Link to comment Share on other sites More sharing options...
jdarkme Posted June 4, 2007 Share Posted June 4, 2007 It's number one in the diagram (the screw isn't exactly the same shape but it's in the same location). Quote Link to comment Share on other sites More sharing options...
MatMan Posted June 6, 2007 Share Posted June 6, 2007 You didn't mention the fuel treatment stuff before. I don't have personal experience with Lucas, but I have seen a video of the after effects of Seafoam. LOTS of white smoke as it burned!! I think it's linked somewhere on this site... To adjust the mixture to a good starting point, adjust the screw as seen in jdarkme's post all the way shut (up), then back off 2 1/2 turns (down) on both carbs. Then you can play with the vacuum sync tool to get the same volume through both carbs with screw #3 IIRC. Quote Link to comment Share on other sites More sharing options...
Austin240Z Posted June 6, 2007 Share Posted June 6, 2007 I have seen a video of the after effects of Seafoam. LOTS of white smoke as it burned!! That does not happen unless you pour seafoam DIRECTLY into the intake manifold via a vaccuum line, normally the brake booster line. I have done this in a dozen cars, including my own... adding seafoam or Lucas Fuel Injector cleaner(i sell both at an autoparts place) will not cause your car to smoke like that if poured into the gas tank. Atleast, I have never seen it happen. To the best of my knowledge, most of the time when you have white smoke, and I'm talking a pure white with no bluish tint, it is usually water/coolant burning. The majority of my car knowledge is limited to newer type cars, EFI. My carb knowledge is limited. The big question is, are you losing coolant? If not, then I'm not sure what's going on. Like i said, carbs arent my strong point yet. good luck to you Quote Link to comment Share on other sites More sharing options...
justinr54321 Posted June 6, 2007 Author Share Posted June 6, 2007 Well, I am not losing coolant, and it did start happening after I put in the cleaner. I've heard of it before, and I had someone take a look at it, and they told me I was running rich. However, my carbs do need to be rebuilt, for I've tried getting then tuned in, and nothing, for I don't get the full RPM range, unless its my crank/cam shaft that is limiting it. This car was with a 17 y/o kid who let it sit for almost a year, and he got it off of some guy who was starting to restore it. I don't know what he did to it, so I am more than likely going to end up doing a full engine rebuild myself later down the line, getting it set up for a turbo... Any-hoo, thanks guys. I will try adjusting the carbs again tomorrow, and if no luck, then I will end up rebuilding them. Then save up some money and start buying the parts I need piece by pice for the engine rebuild. Shoot, I wish one of my friends would put me up on overhauling, then most of my problems would be solved, lol. Quote Link to comment Share on other sites More sharing options...
justinr54321 Posted June 7, 2007 Author Share Posted June 7, 2007 Well, I took off my carbs this morning, and found a bad gasket on the front carb, so I was getting coolant into the intake manifold, go figure, but after this rebuild of the carbs, and new gaskets, everything should be running fine. Thanks for all the advice and help. Quote Link to comment Share on other sites More sharing options...
justinr54321 Posted June 11, 2007 Author Share Posted June 11, 2007 Current update: Took off my valve cover today, and found 4 rocker arms that were not on, so in essence, I was running on 2 cylinders. Put them back on, no smoke at all. Now, I just need to get my hands on a set of feeler guages and a carb sync tool so I can finish out the engine. I wish I could get my hands on the guy who did work on the car before me and give him a piece of my mind, for I was almost stranded the other night, whcih is not fun. Well, more updates to come. Quote Link to comment Share on other sites More sharing options...
justinr54321 Posted June 13, 2007 Author Share Posted June 13, 2007 Ok, been looking for a carb sync tool, and don't know which one to get. What would a good one be to purchase? Quote Link to comment Share on other sites More sharing options...
MatMan Posted June 13, 2007 Share Posted June 13, 2007 I think I have one by Matco, but I think as long as you don't drop it, any one would do. Quote Link to comment Share on other sites More sharing options...
jdarkme Posted June 13, 2007 Share Posted June 13, 2007 You should get one like this one because it doesn't block the airflow like the other model does: http://www.thezstore.com/page/TZS/PROD/TE/60-9976 Quote Link to comment Share on other sites More sharing options...
justinr54321 Posted June 14, 2007 Author Share Posted June 14, 2007 You should get one like this one because it doesn't block the airflow like the other model does: http://www.thezstore.com/page/TZS/PROD/TE/60-9976 I thought about that one, and also this one: http://www.jcwhitney.com/autoparts/Product/tf-Browse/s-10101/Pr-p_Product.CATENTRY_ID:2008076/p-2008076/N-111+10214+600017960/c-10114 Just don't know which would be the better pick. Probably the one you mentioned above. Thanks for the help. Quote Link to comment Share on other sites More sharing options...
jdarkme Posted June 15, 2007 Share Posted June 15, 2007 I thought about that one, and also this one:http://www.jcwhitney.com/autoparts/Product/tf-Browse/s-10101/Pr-p_Product.CATENTRY_ID:2008076/p-2008076/N-111+10214+600017960/c-10114 Just don't know which would be the better pick. Probably the one you mentioned above. Thanks for the help. Although I can't see a picture of the other one, by the description and the review someone gave it it seems to be pretty much the same thing and it's also cheaper, so I'm guessing it's not a bad choice either. Quote Link to comment Share on other sites More sharing options...
justinr54321 Posted June 15, 2007 Author Share Posted June 15, 2007 I bought the one you reccommended because I've read a lot of bad reviews about JC Whitney. Anyhow, I've been searching for a shop manual for my 240z. Does anyone have one they can email to me? Its driving me batty. I have the Haynes manual, but itssketchy at best when it comes to diagrams and stuff. Thanks. Quote Link to comment Share on other sites More sharing options...
justinr54321 Posted June 20, 2007 Author Share Posted June 20, 2007 Hey guys, thanks for all the help, got my carbs tuned out and mostly everything else. She is running pretty sweet now, with a few exceptions. I'm still looking for pics of the stock engine so I can get everything hooked up correctly for the vacuum system, unless there is someone in my area that could give me a hand with that. Also, my RPM's are redlining at 5500. I'm thinking that it might be a timing issue, but I'm not too sure. The last time I rebuilt a car was when I was 15-16 years old, helping my uncle rebuild an old 1979 cougar. Well, I'm off to bed, I've spent too much time up and about after work. Laters. Quote Link to comment Share on other sites More sharing options...
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