No fuel Issue 71 455

Hi All,

I am literally ready to pull my already thinning hair out over this.

Last year in April, after a shamefully long slumber since the last attempted start (7 months?) I went out to fire up my 1971 GS 455 Stage 1 four speed. Motor is a TS block, non matching #'s. Iron heads to Stage 1 specs. Carb is a correct 7041242 Rochester.

Car wouldn't start. It had started and run just fine in the previous Fall.

Established pretty quickly that I had spark. Squirted gas in the fuel horn and she fired but died as soon as the gas was gone. I disconnected the fuel line and had my son crank the motor and gas came out.

I removed the carb (which was purchased in 2006 as a 100% rebuilt unit and installed when the car was restored in 2016 - less than 100 miles run time in it's life) and put it on my bench. I am not a carb expert and what little I do know is Holley. However, I didn't find anything obviously wrong. Float wasn't stuck, etc.

I put it back on and hit the online threads. Several good guys from the Facebook Buick GS thread said that the crappy ethanol gas may have ruined my fuel pump while sitting for so long. I puttered around with some other ideas then a few month back I got an OEM Stage 1 fuel pump from the GSCA.

Put it on last weekend and figured I'd be up and running today. NO LUCK.

Same exact condition. This time, to be sure about where my problem lies, I installed a cheapo Mr. Gasket clear fuel filter in line before the carb. I cranked the motor and very little fuel filled the filter. I once again squirted gas into the fuel bowl and she fired up, but shut down as soon as it was gone.

I'm at a loss. I visually inspected as much of the fuel lines as I could going back to the tank and I don't see (or feel) any obvious breaks or dry rot cracks (thinking maybe I'm sucking air somewhere).

Is there something in the Rochester that could be my problem?

Any other ideas? I'm literally losing my mind and I have a $30,000 garage ornament.

Thanks

Tom

 

Tom, go back and check all your fuel lines they may look fine by the naked eye if they feel real spongy they could be collapsing from the suction from the fuel pump I would replace all the rubber lines and try again if it still won't start try disconnecting the return line on the fuel pump that will raise the fuel pressure see if it starts if it doesn't it could be the sock in the fuel tank disconnect the fuel line from the tank make it long enough so you can put it in a gallon container full of gas see if you now have your pressure going to the carburetor if so you know it's the sock in the fuel tank. Now if you still don't have fuel it your new fuel pump. Tom The gas they sell today does nothing but Ruing old-style rubber fuel lines you could try fuel injection fuel lines they are more compatible with today's fuels. They won't be concourse correct but you won't have a problem when your car sits for a while It happened to me with my convertible when the car is idling you can see the fuel line from the fuel pump to the fuel line actually collapsing as the car sitting there idling . Did you check the fuel filter in the carburetor ?

 

The alcohol in fuel today wreaks havik on the fuek system, including hoses. I don't use anything but fuel injection hose on ANY hoses I replace. I had the same problem as you & it turned out to be the needle was stuck in the seat from alcohol corrosion. Took the needle out & cleaned off the debris & wala problem solved. You need to remove the top of the carb. OR, you could try tapping the fuel inlet with a small hammer while cranking. This may loosen the corrosion.


Tom T.

 

Thanks for the advice. I actually found a place about an hour from me where I can get ethanol free 91 octane gas. I filled the tank with it and some octane booster last summer. A couple of the rubber lines were for sure spongy. The one closest the fuel pump was particularly soft. Maybe I'll replace that one (also likely the easiest to get at) and see what happens. Thanks again!

 

If you have fuel flow to the carb but it will not start remove the airhorn, gasket, power piston/metering rods, splash guard and float. When the float is lifted out it should pull the needle out of the fuel inlet seat if the clip is being used at attached to it.
Not uncommon for the need to get stuck on the seat after long periods of sitting and drying up. When they get stuck it will not allow fuel to enter carburetor.

No need at all to avoid ethanol fuel far as the carburetor is concerned, but if it's been 10 years since it had new internals there is much better stuff out there now that will hold up fine in this new fuel......Cliff

 

Thanks to all for your input. This one really confused the daylights out of me. Ended up replacing fuel pump (with an OEM stage 1 piece from GSCA), rubber fuel lines and stainless pump to carb line. In the end I believe that Cliff R nailed the problem. I removed the top of the carb and sprayed some cleaner in there and made sure the inlet needle (which has a RUBBER tip) was not stuck. Put it back on and she fired up. Now I need it to stop raining and snowing here in PA so I can get some run time on her! Thanks again to all.