Fuel filter direction

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milescook
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Post Tue Jun 11, 2013 4:19 pm

A few months back I replaced the fuel filter. I ensured the arrow pointed in the same direction. Fuel pump gave in - after 100,000 miles so fair one.

However, sometimes on startup after stalling (because the revs are too low and the ecu has been woken up - I use a battery isolater), it sounds like it's not getting enough fuel.

After looking hard at the fuel filter, the arrow goes in the opposite direction to fuel lines to the engine, and points towards a pipe that goes up through the car *somewhere* - to me that sounds like the thing was never on the right way round. I know there is fuel return from the engine - does it go through the filter?

So I'm thinking of turning it around. Better still, should I use a new filter? I wonder because the new one I replaced, if the wrong way round, will have all sorts of crap in where it shouldn't and would be a bad idea?

If so, I have this filter, which has no arrow at all!

Image

If you can help me with this dillema, much appreciated! Don;t want to knacker a new fuel pump... cheers!
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Motorhole
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Post Tue Jun 11, 2013 4:31 pm

On my car, the return pipe goes straight to the tank, not through the filter.
milescook
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Post Tue Jun 11, 2013 4:34 pm

I should add, it's an 88 320SE 2 door.

Cheers MH.
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milescook
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Post Wed Jun 12, 2013 8:27 am

Should I use the new filter instead of the one that was the "wrong way" round? Also can anyone help with the direction of the one pictured?

Cheers!
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Motorhole
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Post Wed Jun 12, 2013 8:29 am

If you don't get a response, I'll check mine out when I'm down the garage tonight as I can't remember off the top of my head.
milescook
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Post Wed Jun 12, 2013 9:15 am

:D Ta.
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rix313
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Post Wed Jun 12, 2013 12:40 pm

For the cost of them fit a new filter. It needs to go on the high pressure side with the arrow going the same direction as the flow of fuel.
milescook
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Post Wed Jun 12, 2013 12:48 pm

Have a new filter ready to go, but it has no arrow or indication which way to go (pictured).
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milescook
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Post Wed Jun 12, 2013 4:22 pm

According to an image search for the below:

https://www.google.co.uk/search?q=fuel+ ... 836#imgrc=_

All the filters appear to flow with the filter lip towards the engine. I guess that's all I have to go on :mad:
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daimlerman
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Post Wed Jun 12, 2013 4:37 pm

I'm guessing here,but I would work on the basis that the 'top' of the filter allows you to read the writing....or top as in direction of flow....
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Motorhole
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Post Wed Jun 12, 2013 10:36 pm

Had a look trying to feel through the pipes to see which end goes where. It FEELS like the longer nozzle is tank side and shorter nozzle is engine side. Not 100% on that but it agrees with what Daimlerman and your pictures suggest.

Edit: in fact that appears correct as my fuel flows in the direction of the arrow, which is shown in this pic along with the nozzles :) Image
milescook
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Post Wed Jun 12, 2013 11:07 pm

Ok cheers will install the new filter in this direction
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milescook
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Post Sat Jun 21, 2014 10:46 am

Just got round to sorting this... will see if it's any quicker :D
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