Carb and Starting questions

[KenshinX]

Well Today since I wasn't working or busy I decided to do a little maintenance and fire up the Z. But first I went to Autozone to pick up a fuel filter because my father let me know I needed one. luckily they had (one) in stock well I got back home and attempted to at least start her up and no luck. I sprayed a bit of starting fluid to help and all I got was a flicker no full run. So I kept trying for the past 1hr and no luck The battery is hooked up the plugs are in the right position because its been started before so whats the problem?

While trying to figure out why she wont start I was looking at the carbs and the pictures from the Haynes manual of the engine and something doesn't seem right. There are two hoses that do not hook to anything. In the picture the hoses hook to the filter box, but since the car did start up at once I'm not sure if this is set up right or not maybe someone could fill me in.

BTW: The hoses did leak fuel once before in an attempt to start a while back, but did not today.

And I never got a chance to install the Fuel filter.

[Walter Moore]

The first picture is the hose from the float bowl vent on the front carb. It goes to the fitting where the left end of the hose in the second picture is incorrectly attached. The left end of the incorrectly attached hose in the second picture goes to the float bowl vent in on the rear carb.

Neither of them has anything to do with why it won't start, unless they are plugged.

[Zs-ondabrain]

so in other words.... The hose in your hand in pic #1 should'nt be plugged and should go to the left nipple in pic #2. The right float bowl should also have a hose going from the outlet to the right nipple in pic #2.

If the hoses are plugged or blocked off, the fuel cannot flow into the carbs.

Change the fuel filter and the oil while you're at it. ONLY use NGK plugs and wires and renew the cap and rotor every once in a while with NISSAN parts. (Nippendenso) works just as good.

Fuel and spark are the number one priorities in troubleshooting a "won't Start" Z.

Good luck,

Dave

[KenshinX]

Thanks so much so far guys, seriously.

The only problem is I cant find the fuel filter on my Z its been moved I believe because looking at other Zs its not on the wall near the engine bay lamp. Also I have 2 oil filters which I find very strange one is the original filter (85A) the other is a huge after market with a gauge attached .

Heres a fairly old picture, but the filters are the same right now I have blue NGK plugs and Wires.

[xray]

Check in this order:

1) Air--easiest one. Check your SU carb piston movement. remove the air cleaner (for now). Turn your idle speed screw in a turn or two to open the butterfly.

2) Fuel--change the filter, check your float bowls--replace the gas if it's old. Does your choke work? If you haven't changed the filter, why did you expect it to run?

3) Spark--plugs are good, normal gap. Check for low resistance in your spark plug wires and HT wire from the coil. Check your coil resistance. Place a metal punch in the end of each spark plug wire, hold the wire (by the insulated part with a rubber glove) near the valve cover while someone turns over the engine--do they all spark?

If you have all three your car should run, even if poorly. Compression and timing are two other important points, but should be dealt with once you get these first three under control.

Steve

[Zs-ondabrain]

Your first problem is in the picture you posted..... The breather hoses for the float bowls are connected to each other. I corrected it with white lines in the photo below... Your carbs CANNOT BREATHE with the float bowls connected to each other.

The second problem is "Where the hell is your fuel line?" Follow the fuel lines from the carbs. They are supposed to go to a fuel rail that wraps around the valve cover and over to the fuel filter where you pointed out "is missing"

Find the fuel lines and get a filter on there.

Take off those hoses on the carb and air cleaner box and put them from the float bowls into the airbox via the nipples.

get back to us when that's done and the fuel problem is corrected. Can't help any more till that's done.

[xray]

BTW: The hoses did leak fuel once before in an attempt to start a while back, but did not today.

I assume you mean "leaked from the end of the hose after I pulled it off to see if fuel was getting to the carbs," right? If it's really leaking then , obviously, new fuel lines are in order...

[KenshinX]

Yea the PO didnt know what the heck he was doin period.:tapemouth

Thanks guys.

[Zs-ondabrain]

OK. so the picture from the first post (#1) shows the fuel line going to the frame rail on the drivers side, follow that and see if you can find a filter and then change it.

If you can't find one. Install one filter per fuel line before they get to the carbs and you should be safe till the next problem arrises.

That's one hell of a set-up so you might wanna be patient with it.

Dave.

PS you can almost see how the float bowl tubes should be in the picture below....

[KenshinX]

Alright so I connected the hoses in the right places and when I attempted to start it. The rear float bowl hose that I attached to the rear nipple is leaking fuel and wont stop whenever I turn the car on dont want to start for the fear of a flash so should I just let it leak until it stops? or is there something terribly wrong?

I followed the lines and couldnt find the Filter so Imma have to put on on.

[Bruce Palmer]

I'm guessing the needle and seat are sticking open. Tap on the float bowl with a screw driver handle and see if that doesn't jar it closed. It's pretty easy for a piece of grit to hold the needle open.

When the flow is happening are you getting concurrent flow into the throat of the carb from the fuel nozzle in the bottom of the throat?

Once you start chasing spooks in your carb system, it's maybe time to take 'em off and go thru them.

[beandip]

Alright so I connected the hoses in the right places and when I attempted to start it. The rear float bowl hose that I attached to the rear nipple is leaking fuel and wont stop whenever I turn the car on dont want to start for the fear of a flash so should I just let it leak until it stops? or is there something terribly wrong?

I followed the lines and couldnt find the Filter so Imma have to put on on.

If you have fuel coming out of the float chamber vent, the shutoff has failed. Either the needle and seat is shot or the float could be full of gas and has sunk to the bottom thus holding the shut off wide open . As Bruce said tap on the float chamber cover with a screw driver handle . If this has no effect then the cover must come off and find out what is wrong. Be vary careful with leaking gas because it will be running onto the exhaust manifold. Have a fire extinguisher handy or a water hose charged and ready . I would have one person watching the carb while another is turning the key. Keep us posted. With a flooded float chamber , it will be difficult to start the engine because raw gas will be running into the intake. Gary