How much pressure would you expect from fuel pump?

[defecat0r]

Hey guys, so i'm trying to diagnose a problem with the old VN. It's running great(ish) on LPG, but barely running at all - missing and spluttering and carrying on when run on petrol. Doing a bit of troubleshooting has led me to look at the fuel system.
I pulled off the fuel filter today, and turned the ignition on to prime the pump, with the pipe directed into a milk bottle. I was EXPECTING a good solid jet, kind of like turning on a hose, but all i got was a bit more than a trickle.
What kind of pressure should you expect from one of these internal, high pressure pumps?

On a side note, my fuel pump died about 2 months ago, and i put a new one in that i picked up from repco (think it was fuelmeister brand?). The pump sounds fine when it primes.

Cheers!

 

[Tasmaniak]

upwards of 70psi usually into a sealed system.

 

[cor3yz]

You will find that if the vehicle always runs on lpg the injectors may need a good clean.
Also I've experienced a high number of faulty fuel miser pumps after a few months, and spoken to a fuel miser rep and he says they are aware of the problem but are unsure of the cause. They just accept a high warranty rate.
So if you have low pump pressure it's likely to be the pump

 

[defecat0r]

You're probably right about the injectors needing a bit of a clean, but i've had the rail out and they all squirt properly when i turn the engine over so i don't think they're the cause of THIS problem.
I guess what i'm asking is, can i diagnose the pump as being the cause of the problem by looking at the stream of petrol it's pumping out, or do i need to spend $40 on ebay for a fuel pressure gauge? Is it possible these things only have a slow flow rate, but still pressurize the rail to the 70PSI or so they're meant to be at? Do you guys rekon i should be seeing a JET of petrol when it primes, or is a bit faster than a dribble normal? I understand that probably not many people piss around with troubleshooting like i do

 

[Tasmaniak]

I would expect a pretty good jet...

 

[07GTS]

u should have a good stream coming out of the pump, sit the pump in a bottle of fuel and hook it up and have a hose on the outlet facing back into to bottle so it dosnt run dry and u should get a good stream, if its trickling out its either not getting fuel or blocked or stuffed, also when u run lpg the fuel pump is always pumping so if u run out it will still be going and burn itself out, some pumps will melt themselvs solid within 2 mins of running dry...

 

[defecat0r]

OK thanks for the replies lads, I guess it's pretty likely that the pump is munted.

I'll take the pump out and put it in a bucket and see how it goes, that's a good idea!

Cheers!

 

[07GTS]

ive got a big pump in my ve and just for a reference mine will empty a icecream container in bout 3-5sec but not sure on the flow of yours so could be like 10-15 sec