engine and drivetrain Constant Buzzing of 5series Fuel Pump? Opinions Please.

[PaulTWinterton]

I'm worried about my new (535i) fuel pump that I retrofitted yesterday into the tii.

 

All went well and on initial start up the pump buzzed and then was quiet.  Very nice.

 

After diligent safety checks I went for a long freeway drive @ 70-85mph.  Ran great.

 

When I got home and sat with the engine idling I could hear the pump buzzing continuously with a varied sound, kind of like oscillating.

 

No leaks, no fuel delivery problems, not hot to touch and no interference with the body or half-shafts.  Just the sound (so far).

 

Please, anyone with one of  these pumps, let me know your experience good or bad.  I need to know if this is an issue or NOT.

 

Thanks for reading and replying.

[AustrianVespaGuy]

Pull the pump back out and make sure there's nothing clogging up the inlet and causing the pump to cavitate.

[ray_]

Yeah. Look for blocked screens, etc...

[PaulTWinterton]

Cavitation. I wouldn't have gone there. But it's probably the only variable left.

Surprisingly, I drove a lot today and didn't hear the pump at all. Still worth checking for intermittent blockage.

I'm on it. Thanks.

[Hans]

Which 5 is this? So it fits in the tii tank and has the right pressure?

[TobyB]

It might simply be the bypass valve- the tii at idle is a LOT less fuel- hungry than a 5er.

 

That would also explain why you don't hear it when you're running around.

 

Also, fuel temps- as fuel gets hotter, it's more prone to vaporization,  which makes

cavitation easier, too.  You do have a heat shield between the exhaust and the tank,

don't you?

 

(guessing)

 

t

[PaulTWinterton]

TobyB,

 

I was considering the bypass valve but hoped that it was functioning as it should...your statement verifies what I think.

 

Heat shield between exhaust and tank?  I don't think so.  Since when?  Not a stock part right?  I've never heard of that.

 

Yesterday, when it happened it was just after a spirited run on the freeway for an hour.  Usually enough time to get the engine to peak temperature.

 

Today, after another fast run it was completely quiet.   I'm still going to re-check fittings and filters for debris.  Shouldn't be any. I'm a clean freak.

Edited May 4, 2015 by PaulTWinterton

[PaulTWinterton]

Hans, The 535i pump retrofits for the tii fuel pump that is under the car.  With a bit of splicing of connectors and rerouting of the fuel lines this more modern pump replaces the NLA tii pump.

 

There's a good how-to at:

 

my2002tii.com

 

It shows the process and part needed.

[ray_]

My vote is the in-tank screen. Unless you've seen it very recently. And your tank is not rusting.

 

Cheers,

[PaulTWinterton]

I replaced the in-tank screen 3 years ago and no, I haven't looked at it recently.  Tank was not rusty the last time I looked.

 

We'll see!  I'm checking it this week.

[TobyB]

There is heat shield between the tank and the muffler.  Or there should be!

 

Honestly, I've only seen one or 2, but they looked factory.  Stamped sheetmetal with a flanged edge?

 

I made one for the race car, and I've seem them on other cars at the track that use a relatively stock exhaust configuration,

along with track cars- but they all looked custom.

 

And I'd recommend one to ANYONE who has a 2002!

 

t

who doesn't like boiling fuel

[PaulTWinterton]

I'll look under the car, but I'm pretty sure there is nothing there that looks like a heat shield.

 

Side note: Toby are you racing at the Portland Vintage July 9-12?

[rstclark]

Regarding the heat shield, If you check the fuel system parts diagram at Penske Parts you will see it as part number 161111114997 called a Protection Plate     and it is   NLA 

Really simple, It slips on the seam of the gas tank and is held in place by the gas tank mounting bolts

If your gas tank has ever been removed it would have slipped off the tank and possibly it wasn't re-installed

They must be available on the used market . Since it separates the tank from the muffler  I wouldn't be without it

 

Rob

[PaulTWinterton]

161111114997

 

So I looked at Penske and DID NOT FIND #161111114997 in the tii fuel supply microfiche.

 

I DID find it in the stock 2002 fuel supply diagram.

 

Was does that mean?  Not required for tii?  A mistake?

 

Learning something new today.

Edited May 4, 2015 by PaulTWinterton

[peterschop]

http://www.realoem.com/bmw/enUS/showparts?id=2558-USA-05_1969_114_BMW_2002&diagId=16_0382#16111114997

 

Looks easy enough to make one up.