[urq] Warning about Fuel Pressure Accum.

[Ben Swann]

As you mention, when operating correctly, the accumulator should help maintain the fuel pressure to around 35 PSI after shutoff if there are no leaks in the system.

The FP accumulator also act as a damper to smooth out pulses/spikes in the pressure.  Analogous to the vertical tube a plumber would install to prevent water hammer when a faucett is closed rapidly in a plumbing system, but also similar to the water pressure accumulator used on well fed systems - a tank that holds water with a bladder full of air at the top.  The accumulator on the fuel injection system uses a spring instead of air to maintain this pressure.

As you allude to a faulty pressure accumulator can cause hard starting, long cranking.  I have found more often, a leakdown on the injector side of the system is the problem, and the accumulator is secondary.

Ben

[Please excuse my ignorance but what is the precise function of the fuel
accumulator?
It is supposed to maintain system pressure when the engine switched off? In
other words could this be my problem with cold starts? Hot starts are fine.
Mixture is not a problem during cold starts, once started. The warm up
regulator is working because the air fuel meter shows it is doing it's job.
The problem is that I have to crank it lots before it fires. Is this because
it has lost system pressure over night and I then have to crank for fuel
pump to restore pressure?

Look forward to receiving your thoughts

Keith

'87 WR]