ciavola Posted September 6, 2010 Share Posted September 6, 2010 I am restoring a 71 240z. I just put the motor back in after the rebuild , basically everything is new or rebuilt, rebuilt SU's from Z therepy. new coil, rebuilt distributer, rebuilt fuel pump, the car started and ran badly for about 10 minutes. turned it off to address an oil leak, went to start it back up and it wouldnt start. I noticed the fuel filter was only half full, should it be full? I checked the lines from the tank , I thought maybe it was sucking in air from the rubber lines at the tank. also bypassed the tank and had the fuel filter draw gas from a gas can. still didnt start. I adjusted the distributer timing from full retarded to full advance. checked for spark, its there but doesnt seem that stong, it is only stock coil and distributer but the car ran for 10 minutes before so thats probably not an issue. there is 6 and a half volts on the coil's positive side. not sure where to go at this point. the engine acts as if its going to start but does not. fuel, spark, timing? Chris Quote Link to comment Share on other sites More sharing options...
Pharaohabq Posted September 8, 2010 Share Posted September 8, 2010 try a fresh battery. you should have about 8 volts at the coil. Check your plug order 153624. You might stop and check your timing. Put engine at TDC, put Dist at #1, Cam lobes should be pointing up at a V on cyl 1. All that should say you're okay.. Next check the AFM. it's got a flap inside, push it up and down a few times, and see if that makes a difference. Let us know what you find out. Phar Quote Link to comment Share on other sites More sharing options...
drive185mph Posted September 9, 2010 Share Posted September 9, 2010 (edited) honestly having rebuilt a few different cars and truck I find that you almost never have a new componant related isue it's always something stupid like a disconnected cable, a missing ground or something along those lines. I recomend combing through, assuming nothing and just follow everything to it's completion good luck Edited September 9, 2010 by drive185mph Quote Link to comment Share on other sites More sharing options...
ciavola Posted September 9, 2010 Author Share Posted September 9, 2010 Thanks for the replys, It is a new battery, new distributer, Points, cap , rotor, litterally new everything. Today I found compression in all cylinders is 120, ther is NO vaccume when I am turning the engine over. From what I have read there should be 5-10 of vaccume? when I could get it running for a couple seconds. using the throttle had no effect. also some of the plugs were blackish semi wet. Steve at Ztherepy told me to change the plugs. I did that today, didnt seem to have an effect. A massive vaccume leak? out of ideas. Quote Link to comment Share on other sites More sharing options...
cygnusx1 Posted September 9, 2010 Share Posted September 9, 2010 If the plugs are wet with fuel, vacuum must be pulling fuel into the chambers, no? Â Got spark? Â Cam timing? Ignition timing? Fuel pressure? Â Check the basics. Quote Link to comment Share on other sites More sharing options...
ciavola Posted September 9, 2010 Author Share Posted September 9, 2010 Fuel Pressure is 3-4 pounds, I have checked the timing at least 20 times, started at center, retard, advance. have spark, unless I am doing it wrong. when the crank is on TDC (this is the first big timing mark correct? ) the lighter chain links is on the 1 mark on the cam timing sprocket, distributer rotor is pointed at #1. when it initialy ran for those few minutes it was very uneven, but did respond to the throttle. shouldent there be some vaccume when cranking it over? Quote Link to comment Share on other sites More sharing options...
cygnusx1 Posted September 9, 2010 Share Posted September 9, 2010 (edited) Fuel Pressure is 3-4 pounds, I have checked the timing at least 20 times, started at center, retard, advance. have spark, unless I am doing it wrong. when the crank is on TDC (this is the first big timing mark correct? ) the lighter chain links is on the 1 mark on the cam timing sprocket, distributer rotor is pointed at #1. when it initialy ran for those few minutes it was very uneven, but did respond to the throttle. shouldent there be some vaccume when cranking it over? Yes there should be some vacuum.  Are the plug wires crossed?  Mixed firing order can produce those symptoms.  Sorry if my advice is basic, but it sounds like something basic is off. Edited September 9, 2010 by cygnusx1 Quote Link to comment Share on other sites More sharing options...
ciavola Posted September 9, 2010 Author Share Posted September 9, 2010 double, tripple , quadrupple checked all things timing. I reran the wires just to be sure. I am almost to the point of pulling the carbs an intake off just to check the gaskets. i am using a intake\exhaust gasket from MSA, stock intake, 3 into 2 headers. everything on the intake has been plugged off. I only know how to check for intake leaks if the engine were running. Used no sealer on the carb gaskets or intake. Quote Link to comment Share on other sites More sharing options...
ciavola Posted September 12, 2010 Author Share Posted September 12, 2010 found the issue, the condenser that came on the rebuilt distributer was defective. now i cant get the car to idle below 1200rpm... Quote Link to comment Share on other sites More sharing options...
drive185mph Posted September 13, 2010 Share Posted September 13, 2010 Dude way to fight it out, you have clear progress. take it for a drive despite the idle issue to make youself feel better and conquer the idle tomarrow good job Greg Quote Link to comment Share on other sites More sharing options...
ciavola Posted September 15, 2010 Author Share Posted September 15, 2010 would love to but no brakes yet, I put a zx master and still have to bend the lines. Quote Link to comment Share on other sites More sharing options...
ciavola Posted September 19, 2011 Author Share Posted September 19, 2011 Ok, The car has basically sat for a year while I moved. looking for any help I can get. The car will not idle consistently. I can play with the choke to get it to start. it will then run(sometimes) it will usually start climbing in rpm's. even if I play with it and can get it to idle at 1200 rpm, it will occasionally spit throuh the carbs and will still die eventually. very inconsistent. Again the carbs are from ztherepy, basically everything is new. if it was just a carb issue. you would think I would be able to get it to at least stay running. I cant seem to find any obvious vaccume leaks. Any Help is Greatly appreciated. Chris Quote Link to comment Share on other sites More sharing options...
beermanpete Posted September 19, 2011 Share Posted September 19, 2011 Ok, The car has basically sat for a year while I moved. looking for any help I can get. The car will not idle consistently. I can play with the choke to get it to start. it will then run(sometimes) it will usually start climbing in rpm's. even if I play with it and can get it to idle at 1200 rpm, it will occasionally spit throuh the carbs and will still die eventually. very inconsistent. Again the carbs are from ztherepy, basically everything is new. if it was just a carb issue. you would think I would be able to get it to at least stay running. I cant seem to find any obvious vaccume leaks. Any Help is Greatly appreciated. Chris It sounds like the idle mixture is too lean. Check for vacuum leaks. Use a spray cleaner or starting ether to locate vacuum leaks. Spray it at likely places such as the intake manifold gasket, carb base gaskets, and so on. Do this when the engine is cold if possible to minimize the risk of starting a fire on the exhaust. Check the PCV and the brake booster. Disconnect their hoses at the manifold and plug the ports. Other things to check: Throttle opener adjustment (if it is still installed). Ignition timing. Make sure the vacuum advance is connected to "ported" vacuum, not manifold vacuum. Choke cable adjustment. Throttle linkage adjustment. Quote Link to comment Share on other sites More sharing options...
ciavola Posted September 24, 2011 Author Share Posted September 24, 2011 I Checked all the above recomendations and nothing. Does the distributer drive look like it could be a tooth off? Quote Link to comment Share on other sites More sharing options...
beermanpete Posted September 25, 2011 Share Posted September 25, 2011 I Checked all the above recomendations and nothing. Does the distributer drive look like it could be a tooth off? It looks ok to me. How about the compression? Valve clearance adjustment? Quote Link to comment Share on other sites More sharing options...
ciavola Posted September 25, 2011 Author Share Posted September 25, 2011 OK, Not sure why this made a difference, I move the distributer shaft over a tooth and reset the distributer to center. it stopped sputtering and with the choke on it will run 2000 to 2500 rpm. it will stay running now but will not idle or run at all with the choke off. Quote Link to comment Share on other sites More sharing options...
ciavola Posted September 25, 2011 Author Share Posted September 25, 2011 It looks ok to me. How about the compression? Valve clearance adjustment? I checked the clearance again was ok. Compression also ok Quote Link to comment Share on other sites More sharing options...
curbsquirrel Posted September 25, 2011 Share Posted September 25, 2011 I Checked all the above recomendations and nothing. Does the distributer drive look like it could be a tooth off? this happened to me on my rebuild, it looked right just like in the pic, but i was a tooth off, after i moved it a tooth, no more problems...i went thru the exact same symptoms as you..try moving it a tooth, u can always move it back.. hope u get it figured out! Quote Link to comment Share on other sites More sharing options...
ciavola Posted September 25, 2011 Author Share Posted September 25, 2011 i moved it a tooth, it stopped suttering but will not run unless the choke is on. Quote Link to comment Share on other sites More sharing options...
beermanpete Posted September 25, 2011 Share Posted September 25, 2011 i moved it a tooth, it stopped suttering but will not run unless the choke is on. Will it run with the choke off if you hold the throttle open? How are you setting the ignition timing? A large vacuum leak would explain this. Are you sure there is no vacuum leak? Is the PCV installed? Correctly? How about the Master-Vac? Perhaps it is leaking. Try unhooking the vacuum hoses for these at the manifold and plugging the ports. Quote Link to comment Share on other sites More sharing options...
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