1990GL 740 Regina. Replaced fuel pump. Now hard to start after sitting.Think low fuel pressure.What does the accumulator do to pressure. Did not replace could this be my problem.???

 

Why did you replace the pump? Did the car start OK before? "After sitting", how long?
What's accumulator? Do you mean regulator?

 

when it does start, does it run fine? with low fuel pressure, it wouldn't run at all.

the fuel pump has an anti-return valve in it, this is designed to maintain residual pressure when its off so it starts easier, but thats just the difference between the first crank, and a few seconds of cranking, as the instant the motor turns around, the fuel pump should be running and develop full fuel pressure nearly instantly.

 

Car would not start.Bad fuel pump,replaced.Must crank 40 seconds to start.Once started and running its o k.Car will crank and start o k until you let sit for 3 or 4 hrs. NOT sure if part is called a accumulator or fuel pump pulsator.Whatdoes it do????

 

not sure if what part? I'm not famliar with any part called any of those things... the very ancient CIS (K-Jetronic) fuel injection had a pressure accumulator

on regina, the fuel pump is inside the gas tank, that goes to the fuel filter under the back seat, then to the fuel rail on the engine, then to the fuel pressure regulator to the return line and back to the gas tank.

 

I believe you mean the Fuel Pressure Regulator... But I think you problem is the Coolant Temperature Sensor, at least based on the symptoms, that's what I'd look at.

 

I realize this is an old thread, but the part the OP is asking about is referred to as "The double dished stamping on the Regina pump covers a small accumulator to smooth pump pulses" and pictured here: https://www.volvoclub.org.uk/faq/Fue...eplacement.htm

I am in the process of replacing a pump in a Regina system 740 at the moment and can't help but notice it is not a very tight fit between the pump's fuel output fitting and the so-called "accumulator", which is more or less a sleeve that slips part way over that fitting. The metal line gets inserted into the top end of this "sleeve", but there remains a gap between the end of the pump fitting and the end of the metal fuel line. This seems to me less than likely to deliver fuel consistently, since this is a high pressure system; everything else has to be so tight, with crush washers at the filter, a fuel pressure regulator and other high-pressure fittings, and then there's this thing with a sleeve where two ends almost meet, one delivering fuel at high pressure, the other tasked with delivering that fuel on. But when the system is attempting to pressurize, it seems likely that this "connection" will present a weak link, allowing fuel to bypass its intended route and spray past the metal tube. My question is: is this "accumulator" or "pulse modulator" necessary? I'm thinking of ditching it and replacing it with another section of high pressure fuel line like the one elsewhere in the pump assembly. Any thoughts?