1971 2800 fuel filter location?

[YoAdrian]

Hi all,

Hopefully this is an easy question... I've been hunting around the engine bay, under the car and in the trunk and just can't seem to find the fuel filter. I've got a replacement in-line one but can't seem to find the original. Also, is there another filter for the return line as well? Thank you!

Adrian

 

[HB Chris]

Do you have a CSi or a carb 74? (Add your coupe to your signature line). The CSi was mounted on battery tray, I don’t think the carb coupes had a filter as the pump had a fine screen in it. Just put one on the firewall between pipe at bottom of fender and the carbs if that is what you have.

 

[YoAdrian]

Sorry -she's a dual zenith 2800 bavaria, I am aware of the screen that looks like a thimble inside the mechanical fuel pump located on the valve cover -is that all she's got to filter fuel?

 

[HB Chris]

Yes, but you can add a metal CSi style filter before the carbs. I would never trust the plastic style as they can crack.

 

[Dick Steinkamp]

Here is an example of what Chris mentions...

 

[YoAdrian]

@HB Chris Thanks a million! Now I can stop hunting for an in-line filter... I'm honestly surprised there isn't any in-line filter similar to the one in this e9 thread, I appreciate the tip on using the metal filter!

 

[YoAdrian]

Thank you @Dick Steinkamp I was peeling back the firewall foam trying to look for a filter back there in that position. I'm just so surprised there isn't an in-line filter, I was following the fuel line all over the place and just knew there had to be one somewhere -I guess not!

 

[deQuincey]

Sorry -she's a dual zenith 2800 bavaria, I am aware of the screen that looks like a thimble inside the mechanical fuel pump located on the valve cover -is that all she's got to filter fuel?

if you have a mechanical pump, it depends on the type,
original old mech pumps had a mesh filter inside, you access the filter through an hexagonal nut
it is advisable to add a filter in the line as well as an anti-return valve
but if you still run your mech pump do not use a metal filter intended for csi versions
you mech pump for carbs gives you 0,20 to 0,25 bar pressure, a metal filter is too big and it opposes highly to your fuel pressure, it is inadequate
csi cars operate at 10 times that pressure so the aluminium or other metal case filters are ok for them, but they are not for carbed cars

OME plastic filters (automotive grade plastic) are homologated and do not crack or melt

plus you see through the plastic and you can see actually the fuel there helping you with diagnosis

buy in reputable shops to reputable brands and you will have no problems

knecht, Mann filters, purolator, …are OEM reputable brands from wich you can buy correct plastic filters

 

[HB Chris]

The m10 motor with mechanical pump in my NK with a Weber carb uses the Tii metal filter mounted next to the battery. It works just fine and looks correct.

 

[Christoph]

buy in reputable shops to reputable brands and you will have no problems

knecht, Mann filters, purolator, …are OEM reputable brands from wich you can buy correct plastic filters

So true, not only here.

BMW did not think it necessary to add an extra filter apart from the mesh one on the Zenith cars. On the other hand these cars are now quite old so it might be a good idea. I searched for the filter on my E3 once, too, with no result. We then decided there wasn't any trouble and left it like that. As long as the tank is not too muddy and you don't use the last ten litres regularly, it will hardly cause any issues.

Most people I know, however, use plastic filters, either on the firewall or a few inches further on. It may do good or at least not cause any harm. Some guys also, speaking of Germany, still put Lead Surrogate in the fuel. All is good that makes the owner feel good.

 

[DerSchwede]

Most people I know, however, use plastic filters, either on the firewall or a few inches further on. It may do good or at least not cause any harm. Some guys also, speaking of Germany, still put Lead Surrogate in the fuel. All is good that makes the owner feel good.

There are even long time E3-drivers that add 100-250cc of two-stroke oil (instead of lead surrogate) per fill-up to compensate for the lacking of lublicating abilities in modern petrol, helping lifetime expectancy of injector valves, carb axles and preventing residue build up within the carb…