Hard starting 77 s

My 77 911s is sometimes hard to start when hot and cold too. I ussually have to pump the gas or floor the gas pedal when starting it ( I know this is wrong with fuel injection) but it works, Wha t could be causing this??????PLEASE HELP.
Shawn

I would suspect it to be either hydro-lock and/or a leaking fuel system. It sounds like the fuel pressure is able to back-feed through the fuel-pump. Something about a check-valve at the pump comes to mind. I think this check-valve got moved around for differing years.

Also, the CI$ head-unit could be leaking (hope not).

Good Luck
I suspect Warren will have better insight.

Nick

How can I check if it the CIS head unit? Is it possible to check the Check valve? Does anyone kno where it is on a 77 911s with 2.7 CIS?

Davis,
I've had lots and lots of trouble before trying to start my '76 911S 2.7. The check valve you're looking for would be in the fuel pump. How you check it I don't really know. What also could cause this problem is a defective fuel accumulator. It helps hold the pressure in the system for easier starting/restarting. You might want to check this also.

Jeff
1976 911S

I’ve got exactly the same problem with my ‘74! If I turn the key to the ON position and let the fuel pump run for about 15 seconds before I try to start it - it starts right up. No visible fuel leaks and I replaced the accumulator. It’s got to have something to do with the check valve. It sounds like this valve is “inside” the fuel pump – is this a serviceable item or am I looking at replacing the pump?

Mike