[K Simmons]

Has anyone ever done this? It looks like one could "T" off of the vent line on the top of the bowl and run a clear line to the drain plug and then know exactly what the level of fuel in the bowl is.

This seems too easy to have not been done before, unless I am missing something. If it has been done before, do you have any pictures of the results?

I think I have far too much time on my hands and not enough money in my pocket!!

 

[ZZZZZ]

You are close...

Scott, the former owner of ZTherapy had a kit running clear hose from the drain plug-he used a wire in the tube to help it retain shape. I had this setup on my car-it kind of turned a little brown at the bottom from the header, but it was cool to be able to check your float level at any time. I think they sell them at ZTherapy still...$30, kinda pricey, but if you're lazy like me....

 

[ZZZZZ]

Here's a pic...

 

[Al 260Z]

Re: Here's a pic...

Check out my post below re. SU float level.
http://zcar.com/forums/read.php?f=1&i=222531&t=222531
let me know what you think.

Ztherapy has custom fitting for getting a tube fitting out the drain plug.

I think ya really want to gauge the level in the jet. That's where it matters. Per Factory bulletin referenced below, and the business w/ different needle seats and floats for front/rear carbs, it's clear that Datsun/Hitachi worried about the rearward slant of the engine in relation to the float chamber level.

Later!
Al

 

[steve 260z/300zx]

Cheap and easy way...

I don't care for any of the solutions I have seen as permanent solutions. I wouldn't trust anything less than milling the bowls and permanently bonding some glass.

...but a highly effective and cheap way for tuning is...

Obtain some clear hose, 1/2 inch inside diameter (about a foot). Get a couple of clamps that fit the ouside diameter of the hose (i.e. will clamp to approx 1/2 inch).

Unscrew the drain plugs. Drain fuel. Cut hose in half. Fit over each drain plug opening. Clamp for safety. Tie it up with a bit of wire or something around either the vent pipe or fuel inlet (i.e. to keep the hose straight up against the fuel bowl). Pour some fuel in there to prime the carb.

Start car and check immediately for leaks. You should be able to observe the level of fuel easily in the bowls. As you adjust the floats, you can confirm the level is correct.

I agree with Al that the best way would be if you could peer down the nozzle but I have never had anything close to reliable results that way so it I suggest you approximate with a method like mine. To be honest, I really feel that you need to see the fuel level in the float bowls to do a good job of tuning.