fuel(i think) help please

[rusty510]

i have a stock l16 with a weber dgv on it. it idles fine but it has been dying at high speeds and medium speeds uphill. kind seems like its running out of gas. but ill take it off load and just coast for a min then rev it a little and it will pick up but shortly die again. i have replaced the fuel pump and filter. i have set the mixture everywhere from lean to ritch. i tried raising the float level. i tried messing with the distributor advance but nothing helps. i am wondering if anybody has had a similar issue or if i am over looking something ect. any help is appreciated.

[AtomChurch]

try rebuilding it. mine did that but had more of a popping thing and I rebuilt it and it was fine. also if you tighten the air/fuel mixture screw too tight you can ruin it. does it still have a effect, the air fuel mixture?

[banzai510(hainz)]

ask your self does this do it in the main circut? or when the 2nd barrel is in?

 

I had a carb where it wouldnt run once I got in the main barrel circut. But if I hit the throttle hard it would run better. so I took it apart to rebuild and found a tiny rock in the main jet on the bottom of the float bowl.

 

How I got home was put the choke ON and enough vaccum was created to use the second barrel so the gas would use the 2nd barrel circut.

 

persoanlly I dont like taking carbs apart. You have to remove the choke linkage that goes to the top otherwise the top will not come off.

But its Ez

 

 

I would maybe ck the dizzy also just to make sure the weight didnt jam up and fell off the springs

[banzai510(hainz)]

Is there points on this car dual points?????

[racerx]

How old is that carb? Are you sure you set the float level correctly. There are 2 settings one for plastic float and brass float.

 

 

RacerX

[racerx]

oops I forgot! here is a diagram for float setting.

 

http://www.piercemanifolds.com/Float_Level_1.htm

[racerx]

Also check your coil...mine was doing that at one time and coil, I think primary was going out, replaced it hi-po and it ran good. The car was running okay then get on the freeway and hills and it would sputter and felt like it was running out of gas but actually not enough spark. Let us know what happened.

[hang_510]

i have replaced the fuel pump and filter.

be sure the tank & lines are free of debris.

[rusty510]

ok the fuel mixture has no effect

 

i think it has dual points (i think thats what came stock in 72?)

 

it does not get better if i push harder on the gas so i dont think it is a main circuit problem

 

as far as the float goes i am not sure about exact specs i just raised the bowl's fuel level because i thought it might be too low and causing it to run out of gas.

 

im going to go to the parts store and pick up a coil right now and try that.

 

thanks for all the suggestions ill post up after i try the coil. oh and hainz you brought up points, do you think they might be worn out?

[rusty510]

oh and ill check the dizzy too. and as for the clogged lines i checked the leads from the tank yesterday and they were fine not to say they couldnt be clogged elsewhere. i also messed around with the gas vent tank and recuirculation system. not sure about that but i dont think i have ever seen a datsun with that stuff hooked up :D. i also heard that there is a filter just after the fuel inlet on the carburetor ill check that as well.

 

ill post results tonight. thanks all!

[racerx]

ok the fuel mixture has no effect

 

i think it has dual points (i think thats what came stock in 72?)

 

it does not get better if i push harder on the gas so i dont think it is a main circuit problem

 

as far as the float goes i am not sure about exact specs i just raised the bowl's fuel level because i thought it might be too low and causing it to run out of gas.

 

im going to go to the parts store and pick up a coil right now and try that.

 

thanks for all the suggestions ill post up after i try the coil. oh and hainz you brought up points, do you think they might be worn out?

 

 

If it has these: http://cgi.ebay.com/Datsun-Nissan-180B-200B-76-80-Dual-Points-System-S218V_W0QQitemZ230257830648QQihZ013QQcategoryZ6763QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

 

then you have dual points. Not sure about your taste but I would get rid of that stuff and get pertronix pointless system..there's some guys who like dual points. I've always had a hard time adjusting them. It's okay with single but dual, can be challenging for some.

[datzenmike]

.....i also heard that there is a filter just after the fuel inlet on the carburetor ill check that as well.

 

ill post results tonight. thanks all!

 

Remove the hold down bolt and slide the banjo fitting up and off and you can get at the fine wire screen at the fuel inlet. Banjo fitting? take a good look at it and you'll see why it's called that.

 

Are there any kinks in any of the rubber fuel lines from the tank to the hard lines and from the hard lines to the fuel pump and the carb?

[]2eDeYe]

Why is the dueling banjos playin in my head now? :lol:

[rusty510]

ok the filter in the carb is clean. and the coil didnt help.

so i hooked up a fuel pressure guage just prior to the carb.

while it idles it builds up to about 6.5 psi then as i drive it drops until it hits zero then it dies. start it back up and it rises again. so i am loosing fuel pressure but i dont know why.....

[datzenmike]

Classic pump not getting enough fuel. Blockage or plug in the line. Check the hard line for kinks too. Did you check the rubber hoses for kinks??? Can you blow through the new filter??

 

Take the hoses off both ends and blow out the hard line with air. Use caution GAS and COMPRESSED AIR!!!

 

 

For you Redeye:

 

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[rusty510]

will do! ill post results afterwards. thanks again everyone.

[rusty510]

yep it was clogged lines. the tank had a bunch of junk in it. i took the tank to the radiator shop and had them cleane it out. then i reinstalled it and tried to clear the hard lines with compressed air but i couldnt get them clear.... so for now i just ran soft line under the car until i can get the hard line clear. :D ghetto i know but it should work temporarily. thanks for all your help!