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5 Star Rising

240z Flat Top Carbs. Cant start car.

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First I know that I should throw these Flat Top carbs in the Garbage Can and get some Round tops but I only want to get this car started enough to move it around in my yard instead of pushing it.

 

1973 240z with auto trans all original. Hasn't ran in 20 years. Gas tank is cleaned out, new fuel filter, new fuel lines, put a new set of dual points on the distributor, new cap and rotor, new spark plugs and wires. Both site windows of the flat tops show fuel inside 3/4s of the way up..

 

I CAN GET THE CAR TO RUN ON STARTING FLUID.

 

but it will die out once the fluid is out. Looks to have fuel pumping out of both lines at the carbs. Has factory electric fuel pump AND mechanical pump on this late 73. Blew out fuel lines with compressed air. 

 

I have not checked fuel pressure yet or timing. But car runs on starting fluid. Also thought maybe too many vacuum lines are unhooked and dont have vacuum in the carbs. 

 

Any advice to get this car to just idle and maybe drive around the yard using the factory components?

 

I should also mention I ADDED a throttle spring in a odd spot as once the gas pedal was pushed in it would not retract, it works well now.

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9 hours ago, 5 Star Rising said:

Also thought maybe too many vacuum lines are unhooked and dont have vacuum in the carbs

 

So you have some major vacuum leaks? This will make it difficult to run, and the carbs won't provide the correct mixture. This will be the case with flat or round tops.

 

These carbs don't take much to get running, I think I plugged just about every vacuum port on mine and poured fuel into the bowls and it idled just fine. I did do gasket kits on mine before I ever tried to run them, so ymmv.

 

IMG_20190708_203432.jpg

Edited by ZHoob2004

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On 12/10/2019 at 7:09 PM, bunkhouse said:

 Don't throw them away yet. A few of the folks over at Classic Zcar Club (classiczcars.com) are very knowledgeable about flat tops and state they are actually superior to round tops in many ways. The best thread on the subject is "We're bringin' back the Flat Tops".

Thanks, I found that post, but it doesnt seem to go into detail about the carbs that much. More about restoring a 73 back to stock.

 

I'm going to try to plug any vacuum leaks I have.  The car also has a loud exhaust leak at the manifold, wonder if I have a bad leak on the intake as well possibly causing a big vacuum leak. Wish I could get this thing running long enough to diagnose what the heck is going on without pulling the motor apart first.

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Update: so I got the car running on its own for the first time in 20 years!!  At first I plugged all the vacuum hoses which I'm sure helped a little but the car would still not start, it would do the same thing... try to start but never catch. 

 

I had adjusted the choke cable before and the choke levers would move a little when pulling the choke cable as far back as possible but the car would still not start.  So I got a crazy idea to choke them myself. I put autobody masking tape over both carbs completely and when trying to start, it acted different but still would not start...Then I poked a small hole in each piece of tape on each carb and low and behold she started, it ran rough but it was enough to warm up the car. Then I was able to adjust and balance the carbs with my Air Flow meter.

 

Now it starts every time, but then again I haven't tried to start it when it's cold again yet. But some huge progress was made....There was fiery embers flying out of the engine from all the tree leafs, pine needles and spider webs that had some how got in the motor from sitting 20 years.. I let it burn out the best I could with a garden hose near by just incase.. Tomorrow I will pressure wash the motor again to hopefully get all that debri out. It definitely has a exhaust leak at the manifold and also a coolant leak under the intake somewhere. But SHE RUNS!! , Revs up then idles. Thanks for the input

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