Tii Fuel Pump filter?

[Andy74tii]

Hi folks, I am forging ahead with the 5 series fuel pump conversion path for my tii, but I did notice a number of folks have recommended an inline fuel filter - I believe between the gas tank and the inlet on the fuel pump. Is that the correct location and can anyone offer their experience on this - what did you use and where did you locate it?  Many thanks!

 

Andy74tii

[BarrettN]

The stock configuration for a tii has four filters - a screen on the fuel pickup inside the tank, a wire mesh cone screen filter in the inlet of the stock fuel pump, a metal can filter mounted near the battery on the front of the engine compartment (this is the larger style filter that I suspect that you are asking about) and then there's a wire mesh filter inside the banjo bolt of the fuel input to the kugelfischer (and a cone mesh on the cold start valve inlet iirc). If you have fuel system issues (rust) , best to correct them as much as possible as your #1 priority in my opinion. I'd want all the filters as BMW had them from the factory, adding one between the tank and the fuel pump inlet would be about the only thing to do differently. In theory the screen filter on the fuel pickup should keep any junk out of the pump. I don't think that the 5 series pump has an inlet filter screen. 

[Andy74tii]

Yes, you are correct; the 5 series pump does not have a filter on the inlet. I will put an inline filter between the fuel tank and the inlet on the new pump. Thanks !

[NYNick]

It is located at the bottom of the radiator. Typical metal Mahle type filter.

 

After removing the stock tii pump and seeing its condition, it didn't take a lot of convincing for me to see the logic of an "in tank' replacement. My memory isn't what it used to be, but I think it's a 328i pump? Not sure. Steve at Blunt would remember.

 

Of course there's a pickup screen, but then no filter until the one before the K-pump at the bottom of the radiator. This mind you, after CONSIDERABLE time and trouble removing, cleaning and sealing the gas tank.

 

GL

 

Nick

Edited July 18, 2020 by NYNick

[Conserv]

4 hours ago, Andy74tii said:

Yes, you are correct; the 5 series pump does not have a filter on the inlet. I will put an inline filter between the fuel tank and the inlet on the new pump. Thanks !

Yes, but... there may have been other reasons — relating to pressure and flow — why the factory chose to place the primary filter just before the Kugelfischer. Stated differently, why didn’t BMW place the primary filter before the fuel pump? If you’re particularly concerned because your fuel tank is filthy or rusty, I’d, regardless: (1.) address that problem directly and completely, and (2.) wait to hear others’ actual experience. The 5-series fuel pump is a widespread modification. It works. Someone will have actually tried an additional filter and either succeeded — “no problems in 32,000 miles!” — or failed... I’m just trying to distinguish the people who say “yeah, that sounds like a good idea” from owners or techs who have actual experience with an additional filter.

 

If you look at RealOEM.com, did the 5-series pump have any filtering devices anywhere on the feed line from the fuel tank, e.g., a separate filter, or did it rely solely on a screen in the fuel tank?

(As an aside, many of the screens both on the original fuel pump and in the banjo bolt at the Kugelfischer are missing today.)

 

Regards,

 

Steve

 

[Glen Karr]

When I changed out the pump I was concerned that there would not be a screen/filter between the tank and the pump as per the original design.  I installed a metal canister filter between the tank and the pump (NAPA 3299). It has a 1/2" inlet and outlet.  

Best,

Glen

[jimk]

Putting an honest EFI filter between the pump and the tank will cause cavitation in the pump.  You will know it when it happens and your car will hardly get you home because the cavitation will not stop until you clear the blockage.

EFI pumps flow at pump capacity all the time as opposed to carbureted engines where the flow is only what the engine uses.

Any particle size that passes the in tank pickup screen will pass the pump and is the common practice for EFI systems today.  If there is a tank rusting issue, fix the tank.

[OriginalOwner]

When I installed a -5 series fuel pump 11 years ago, I installed an in-line nothing-fancy fuel filter between the tank and the fuel pump inlet.  No problems noted since then, and I haven't touched it.

    And now that you mention it, I reckon it's time to change it.

 

Cheers,

 

Carl

 

[Mike A]

What jimk posted is correct and should be heeded. Although they perform the same function, A filter (usually paper element) is different than a metal mesh screen. Screens protect the pump on its suction side, and will allow particles to pass that won’t harm the pump but these particles over time will clog a paper filter, which is designed to protect the equipment receiving the fluid . I’d Go with the factory parts in their original location. 

[Andy74tii]

Thanks all for the advice, still moving forward with the 5 series pump.... for those of you who have performed this operation, could you look at these pics to let me know if I have the fuel line routed correctly from the outlet of the pump to the canister? This is how it looked in some other pics but once the install has occurred it is hard to see. the other outlet port from the canister will go to the kugelfischer. Before I bolt it back up and connect the big line from the fuel tank to the front of the pump, I want to make sure I have it right. Thanks,

[OriginalOwner]

Looks OK to me.   As for "correct" ....... it's just a matter of making sure the two are connected and the hose isn't rubbing on anything once installed, you don't want vibration to abrade the fuel hose.

 

AND, don't forget:  on the OUTLET of the fuel pump:  use high-pressure fuel hose everywhere downstream of the fuel pump.

 

And just to "say" it ..... here's reading on the topic ....

   http://www.my2002tii.com/tii-fuel-pump_how-to.htm 

 

Cheers,

 

Carl

 

Edited July 18, 2020 by OriginalOwner

[Andy74tii]

You mean like this? Ha, I remember reading Keith's article when he first wrote it, so pretty familiar with it. Funny, I found something I posted here in 2002, 18 years ago, asking about the availability of the inlet filter, since mine was missing. Who knows how long, but at least 20 years, as long as I have owned this tii. I should have bought the pump then, I suppose, I think they were around $150, which seemed high to me at the time!

[JMMcR75]

I'm in the middle of the same fuel pump replacement that Andy describes. (I had convinced myself that I couldn't start until my QuickJacks arrived.) I'm using the E24/E28 pump 16141179232, Bosch 0580-464-048 shown in Keith Kreeger's exceptional article, and my pump/canister assembly looks like Andy's above.  I plan on replacing the original pump wiring harness back to its connection point in the trunk by the tank, making it easier to include an inertia switch in the wiring to turn off fuel supply in case of accident.  The original pump and harness will be archived for the next owner.  Thank you for the discussion about screens and filters!

 

 

[BarrettN]

[Son of Marty]

Yeah, I'd go a head and clean that tank.