Engine/fuel problem

[Tri-Star]

Well I got it to run decently for a while. Now something’s wrong though. The car sounds raspy, and there’s barley any acceleration. I put new SU carbs, wires, plugs, cap, and rotor on it. The carbs are tuned (as i said it was running fine). I thought it was the firing order, but I brought the first cylinder to TDC and rechecked the order and it was correct, there seems to be no vacuum leaks. So I figured I just got bad gas, because it happened soon after I filled up one day. I noticed there seems to be air bubbling up in the fuel line headed towards the mechanical fuel pump. I took off the fuel strainer, cleaned it out, put it back on, and still same thing. What should I do?

[kenz240z]

Check the fuel line for leaks. It could be that one of the fuel hoses back at the tank has split.

What year is your Z? The '73's have an electric fuel pump back by the tank. There is a filter in the electric pump that can cause fuel delivery problems if it gets clogged with sediment from the tank.

[Tri-Star]

early 74 260, theres no gas leaking

[1 Bravo 6]

G'Day Tristan,

Air bubbles in the fuel lines certainly sounds like a leak in the hose somewhere.

Have you checked around the clamps holding the rubber hoses where they join onto the metal pipes ?. I had a similar problem with my 8/74 260z.

Have you checked inside the distributer Cap for cracks, worn contacts etc. ?

Rick.

:devious: :devious:

[Tri-Star]

I droped the gas tank and blew air through all the lines and im about to take off the rest of the hoses fited on the metal lines. the distributer Cap is brand new. Its def a fuel problem because when i blew air though the fuel strainer i got tons of gunky mess out of it.After i make sure non of the rubber hoses have cracks ill replace the strainer and clean out the tank.

[Tri-Star]

I cleaned out the tank and took off all the hoses. I replaced a few hoses and wrapped some others in electrical tape just to be sure. I got the tank put back in but i don’t remember witch way the fuel gauge wires go on. Dose the yellow wire go on top or dose the back one? If some out could pop their head under the back right tire and check for me that be awesome. I need to replace the "fuel strainer" but the nearest parts store didn’t have one. I think its the same as an inline fuel filter but im not sure. Is it?

[beandip]

A couple of things, You installed new SUs ? Have the carbs been balance and adjusted properly ? You used tape on the fuel lines ? If there is ANY question on a fuel line REPLACE IT ! When you had the tank off did you find any crud in the tank ? Was it rusty inside ? The fuel filters , if they were full of crud as you said , replace them . You may need to do that several times if there is much crap in the tank . There may be screens in the SUs them selves where the fuel line connects to the carb. If they are clogged this could be a problem. Has this engine been setting long with out running ? Fuel gage sending unit , the connections are different sizes , just look closely , there is not a great difference .

[Tri-Star]

The SU's were put on a lil while ago they were adjusted properly and it ran great. No, i taped the lines that were still good, mostly just for astetics. The tank had a little bit of crud in it. Yes i know i need to clean or replace the screens in the carbs.

[1 Bravo 6]

Tristan,

I always check the simplest, most obvious first. Air bubbles in the fuel lines suggests a a faulty hose. However, with the engine sounding "raspy" and lacking acceleration, could also suggest an electrical problem.

Does the in line fuel filter maintain the level of fuel with the engine switched off???????????? If not, .... air leak.

Have you checked the carburettor pistons for smooth operation and damper oil level???.

You said that you've installed new plugs and leads. Have you checked to see if you have a fouled or faulty plug?? Wouldn't be the first time that's happened to a new plug.

The only other possibilities that come to mind would be a faulty condensor or intermittant breakdown of the coil.

Rick.

:devious: :devious:

[Tri-Star]

No more air in the lines!

But it still seems like somethings wrong it dosent rev as fast as it used to.

http://img358.imageshack.us/img358/2117/untitled17wu.jpg

The new fuel filter stays filled when the car is off but its seems low all the time. like the fuel is barly raching the filter. maybe its because its a big filter.

[Tri-Star]

Nevermind, It runs GREAT now! I took it for a little drive and Its back to full power (I love this car ) I guess the fuel in the filter is indeeed low just because its a big filter. Thanks for all the help guys! It woulda taken me x2 as long if i had done this on my own.

Only thing is the fuel gauge dosent work now. I hooked up the wires both ways and it still didnt work. Its bound to just be a louse connection. But just to make sure the yellow wire dose go on the larger connection that has a bit of rubber on it (to keep it from grounding) right?

[1 Bravo 6]

Good news mate,

Glad it's all come together and the car's running well again.

Rick.

:devious: :devious: