240Z wont start anymore (plz help)

[logan1]

Ok so when I bought my 240Z the car would not start.

So i replaced the spark plugs and wires and removed the SU carbs cleaned them real nice and put them back on the car. The car started nicely and i drove it around the block once or twice. The car was running really really RICH. The following day the car started up again no problem but then the 3rd day and now the engine cranks good and it smells like it is getting plenty of fuel but it wont start.

I replaced the ignition coil and took out one of the spark plugs and placed it on bare metal and got a healthy blue spark. I cranked the car for a while and the engine started for a second or two and then died again.

I lifted up the cylinder inside the SU's and sprayed some started fluid into the throat and tried to crank and car but it would still not start.

What should my nest step in trouble shooting be?

[DatsunZGuy]

1. Check your point gap and dwell if you are still running an original distributor.

2. Check your timing.

Good luck!

[1 Bravo 6]

You say that it "SMELLS" like it's getting plenty of fuel. Is that REALLY what you mean??

If so, my guess is that she's flooding badly. You shouldn't be able to smell the fuel unless there's a bad leak somewhere.

Rick.

[stevef1972z]

I would second the flooding. Something is stuck open most likely after the cleaning. I would recheck the carbs, check the floats to make sure they are not stuck.

[biddljj]

Check the floats for proper setting as well.

A 1/2 inch drill should serve as a good gauge for float level.

No just a Z - zdisease

As of yesterday the 240Z is in primer.

[logan1]

I was trying to tune my carbs and cranked the engine a few times and the rubber plug on the balance tube flew off with a lotta force.

[Weasel73240Z]

That rubber plug was covering the PCV valve. Thats no good, and it may be part of your problem. That should be routed to the tube below the distributor that comes out of the side of the block.

[logan1]

Do you have a photo or diagram with desription of the balance bar that i could look at?

[Zedyone_kenobi]

That balance tube should be seeing a vacuum not pressure. It connects to the tube Arne was talking about and it sucks the excess vapors out of the crank case to ensure pressure does not build up. If your getting pressure back through your intake, that means that during the compression stroke, there is a leak path back to the manifold, through an intake valve.

[logan1]

That balance tube should be seeing a vacuum not pressure. It connects to the tube Arne was talking about and it sucks the excess vapors out of the crank case to ensure pressure does not build up. If your getting pressure back through your intake, that means that during the compression stroke, there is a leak path back to the manifold, through an intake valve.

Could it be something simple like having the plug wires connected wrong. Which causes the plug to spark before the inlet valve is closed which in turn causes pressure buildup in the intake manifold and balance tube?

And if so do you count the cylinder closest to the front bumper of the car as cylinder No. 1 or is it cylinder No. 6 :tapemouth

[Weasel73240Z]

Could it be something simple like having the plug wires connected wrong. Which causes the plug to spark before the inlet valve is closed which in turn causes pressure buildup in the intake manifold and balance tube?

And if so do you count the cylinder closest to the front bumper of the car as cylinder No. 1 or is it cylinder No. 6 :tapemouth

Front is 1, back is 6.

Might be time to grab a Chilton's or Haynes manual while your at it. These cars are pretty simple to work on, but if you need that answered, you probably should read up a bit and learn the basics of the L-series motor. It'll make the process much easier. No disrespect, just honesty. Good luck.

[Weasel73240Z]

Here's a pic of my balance tube. The cloth braided hose from the PCV valve goes to the tube under the dizzy.