Fuel pump - Again

[SwanJack]

Hi all, my Chimaera'a fuel pump didn't last the winter lay up. So I bought the one below and fitted it today along with a new filter. Car on acceleration kangaroo's and dies, to recover once the clutch is engaged. To me this is a duff pump as iv'e had these symptoms before and a new pump has sorted it. Does this new pump sound duff( https://youtu.be/ObAvVJ9wOzs ), It sounds like a tin of nail and pulses. Admittedly it's a cheap £40 touch but was bought from what I thought was a decent source (Matt Lewis racing as linked in a previous post).

Thanks for any input

|https://thumbsnap.com/stq9MLcD[/url]

https://youtu.be/ObAvVJ9wOzs

Edited by SwanJack on Saturday 2nd March 18:09

[Belle427]

I'd always advise buying a genuine Bosch pump. Have you checked the voltage at the pump?

[SwanJack]

Yes, just over 11v with the car running. I also wired it directly to the battery and took it round the block. No difference.

[Sardonicus]

Have you checked the inlet supply is unobstructed/not blocked? the gravity feed needs to be unrestricted or noise and pressure problems will ensue if your sure this not an issue then the pump is junk around £70 for a genuine pump why go pattern/aftermarket?

Edited by Sardonicus on Saturday 2nd March 20:44

[KevtheRev]

These pumps are normally very reliable. Two things destroy them, dirt & running them dry.
The only filter protecting them in our cars is an in tank plastic filter.
You imply this is your second pump so I'd suggest one of the above root causes for failure if Indeed you have a pump problem.
Just over 11v across the pump is what you'd expect with standard wiring, engine running. I saw a 2.5v drop from battery on original wiring. After rewiring feed & earth in decent cable, I saw just over 12v at the pump & a 1.5v drop.

[SwanJack]

Sardonicus said:

Have you checked the inlet supply is unobstructed/not blocked? the gravity feed needs to be unrestricted or noise and pressure problems will ensue if your sure this not an issue then the pump is junk around £70 for a genuine pump why go pattern/aftermarket?

Edited by Sardonicus on Saturday 2nd March 20:44

Yes, good flow from the tank when I fitted. Have you got a recommendation for the source of a decent one. Ractech have them for about £120, is that about right these days?

Edited by SwanJack on Saturday 2nd March 21:48

[KevtheRev]

This is the pump you want, Bosch order number: 0 580 464 070
This number will also cross reference to other Bosch part numbers depending upon application.

https://www.bosch-automotive-catalog.com/en_GB/pro...

[Belle427]

I've not checked the other thread but is your filter new after the pump?

[SwanJack]

Belle427 said:

I've not checked the other thread but is your filter new after the pump?

Yes, new filter after the pump. It doesn't have a pre pump filter save for what's in the tank. (Not my thread the other one, didn't want to hijack it!).

[Belle427]

I would have thought that pump would be fit for purpose if a Motorsport specialist supplied it, may be worth giving them a call before lashing out £100 on a new one.
I have a cheaper spare in my boot if you wanted me to post it to you for test purposes.

[SwanJack]

Belle427 said:

I would have thought that pump would be fit for purpose if a Motorsport specialist supplied it, may be worth giving them a call before lashing out £100 on a new one.
I have a cheaper spare in my boot if you wanted me to post it to you for test purposes.

That's great, thanks for the offer, I might have to take you up on it. I'm going to bench test it today and see what kind of noise it makes.

[blitzracing]

Even the Bosch one will sound horrible if its not under full load- ie not holding an output pressure- don't forget the fuel line pressure is regulated by dumping excess fuel back to the tank, so the output pressure wont normally drop much below 20 PSI at any point, so the internal rotors will always have a back pressure to push against. The pumps get noisy if they cavitate, so Id not expect them to sound nice on the bench. TBH you really need to measure the fuel pressure at the fuel rail to see if the pump is fit for purpose.

[SwanJack]

I ran the pump independently with a pipe going from the outlet into a petrol can. The flow was strong and the pump less noisy (as expected by blitzracing). Don't have a fuel pressure gauge but have an old school tyre pressure gauge, the one that pushes out a slide rule. A bit Heath Robinson I know, but just wanted a rough reading (feel free castigate if this is dumbass). On priming it was 25psi and on running the pump constantly without the car running, it dropped to just below 20psi. Didn't fancy doing it with the car running just in case petrol got on the manifold.

Started the car and let it run for a while. The pump got progressively noisier and the pitch increased to the extent that I thought I was in the middle of a swarm of African bees. The car then started to die and the fuel pump dropped off, only to pick up again and the car went back to idle. This happened again until the car shut down. Luckily I videod it, you can just about year the car over the pump!! Any ideas? Thanks

https://youtu.be/7hsf0_P85po

Edited by SwanJack on Sunday 3rd March 15:38

[wuckfitracing]

God that sounds awful. Have you ran the pump from another supply, ie put the feed to the pump into another tank/container of fuel.

[KevtheRev]

The regulator should hold the fuel rail at around 28psi at idle (high manfold vac) rising to 36psi as manifold vac decreases.
If your testing with the engine not running (e.g. switching with rovergauge) you should see 36psi at the rail.

Could your fault lie the other side of the pump, kinked/trapped fuel line? A kinked/trapped fuel line between pump & rail would fit in with low rail pressure & a struggling pump.

Edited by KevtheRev on Sunday 3rd March 16:35

[SwanJack]

wuckfitracing said:

God that sounds awful. Have you ran the pump from another supply, ie put the feed to the pump into another tank/container of fuel.

Not done that, and I did check the flow of the water from the tank. But if I had a poor supply, wouldn't just run standardly bad, not fluctuate in crapness as I seem to be getting.

[SwanJack]

KevtheRev said:

The regulator should hold the fuel rail at around 28psi at idle (high manfold vac) rising to 36psi as manifold vac decreases.
If your testing with the engine not running (e.g. switching with rovergauge) you should see 36psi at the rail.

Could your fault lie the other side of the pump, kinked/trapped fuel line? A kinked/trapped fuel line between pump & rail would fit in with low rail pressure & a struggling pump.

Edited by KevtheRev on Sunday 3rd March 16:35

When it went into my garage in November didn't have this issue. It hasn't been driven since so I can't see how I've trapped/kinked a fuel line.

[Belle427]

Maybe an old rubber hose collapsing when it was parked up?

[SwanJack]

So if I can't find any restriction, would my next port of call be to check the fuel rail pressure and if that is fine, diagnose the fuel pressure regulator for a fault. I'll need to buy a test gauge so would this one do?

https://rover.ebay.com/rover/0/0/0?mpre=https%3A%2...

[blitzracing]

Looks Viable although I cant pass comment on the threads. You do need a serp engine with the pressure take off point in the fuel rail.