Hard to start after setting for several hours., Possible fuel problem, need help Options

[rick1062]

Hi Folks,

I am brand new to this forum and to Porsche in general. I am working on a 1975 914 1.8 engine in California. It is very hard to start after setting several hours, like overnight. It cranks well with the battery and starter but won't start. If I crank it over long enough and after several trys it will fire up. Then it seems to run pretty well. It will restart fine again until I turn it off for several hours again. From a general mechanical stand point it seems like it isn't getting fuel until I crank it over long enough, then it will start and restart. I replaced the fuel pump and filter near the tank up front, but that didn't seem to help.

I could really use some of your experience and help on this problem.

Thanks in advance,

Rick

[timothy_nd28]

(IMG:style_emoticons/default/welcome.png)
Does this car still have the factory fuel injection setup or does it have carburetors?

[rick1062]

(IMG:style_emoticons/default/welcome.png)
Does this car still have the factory fuel injection setup or does it have carburetors?

Thanks for your reply,

The car does still have the factory fuel injection setup.

Once it starts it will restart fine and run well. But something happens if it is parked for several hours or overnight. It is like there is no fuel available to the engine until I crank it for long time.

[TheCabinetmaker]

Sounds like it's flooding. Next time it happens hold the pedal to the floor while cranking. The fuel injection system can hold pressure for several hours. Leaky injectors and two or three partially open valves can put enough fuel in the
cylinders to cause flooding

[timothy_nd28]

Being that this car is new to you, I would start with the basics. Number one, I would check the valve lash. Here's a good instructional thread Krusty's valve adjustment on how to do that. After that is done, it would be good to do a compression test on each cylinder. This will tell you the integrity of the motor. Next, I would turn my attention to the ignition system, look at the cap and rotor and check the dwell angle. You could also consider buying this electronic points This module sets the dwell so that you never have to mess with it. I have found that installing this simple upgrade makes my 914 start up much easier.

After all that has been done, inspect all rubber hoses. The Ljet fuel injection system is extremely sensitive to vacuum leaks. The big rubber S boot that connects to the air flow meter has been known to have cracks, which are hard to see. The fuel injector O rings would be another thing to check.
When your car does fire up, what color is the exhaust?

[ericoneal]

My car had EXACTLY this same problem. I'm going to finish installed my rebuilt engine this weekend, so it will be interesting to see if that fixes it. Never did figure out the cause.