Fuel pre filter help

JKIDD

JKIDD

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I'm posting here since most of the Z forums are full of scammers. I have a 75 280Z & looking to use a fuel filter, pre pump. I just changed the fuel filter I purchased it with (in the engine bay) & cut it open to see what's inside. It was full of greyish brown mud. I have no idea how long it was in there, but the PO had it for 10 yeas & only put 1000 miles on it so I'm guessing a while. 2 issues I'm having. First issue is trying to find a new line. The pump is mounted 90 degrees to the tank outlet, & only about 3 inches away (pic attached). I had to replace this line due to a leak (when I bought it) & couldn't get the new hose to make the bend without kinking. I had to go straight past the pump & make a complete circle back. This required about 18" of line to keep it from kinking. I knew this was a temp option as it went into the axle/suspension area & would eventually chafe thru. I found a universal section (shown below) of hose with an array of bends in it & ordered it yesterday. Hopefully I can make it work. I know & can make this using 3 brass 90's & 4 sections of hose (I saw this on 1 of the Z forums), but that's a lot of clamps (which I consider potential failure points) and it's just plain ugly. Second, the hose is 7/16 & I can't find a clear filter with that nipple size. Anyone know of a clear filter with a 7/16 inlet/outlet? I'm ok with not adding a pre filter as it made it this far. The pump looks pretty old & I'm sure a replacement is in my future.

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Got a temp (or permanent depending on how it goes) fix for now... At least I can move it now...
 

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That style Bosch pump includes an internal filter (screen). But it is not serviceable. And as it gets contaminated it significantly reduces the flow, and causes premature pump wear. So adding a prefilter is a good idea.

Use a filter that is rugged enough for the environment it is mounted in. Personally I would not use a clear plastic one. I prefer a metal canister that is serviceable. That way I can open it to see what has accumulated inside. There's several designs that will work for this.

The hose arrangement to add a prefilter might utilize some prebent hoses made for other vehicles. It appears the hoses you used were normal straight sections, which do not bend well. Be sure whatever hose(s) you use are specifically designed for use with fuel - especially if you have ethanol fuels there.
 
JKIDD said:
I'm posting here since most of the Z forums are full of scammers. I have a 75 280Z & looking to use a fuel filter, pre pump. I just changed the fuel filter I purchased it with (in the engine bay) & cut it open to see what's inside. It was full of greyish brown mud. I have no idea how long it was in there, but the PO had it for 10 yeas & only put 1000 miles on it so I'm guessing a while. 2 issues I'm having. First issue is trying to find a new line. The pump is mounted 90 degrees to the tank outlet, & only about 3 inches away (pic attached). I had to replace this line due to a leak (when I bought it) & couldn't get the new hose to make the bend without kinking. I had to go straight past the pump & make a complete circle back. This required about 18" of line to keep it from kinking. I knew this was a temp option as it went into the axle/suspension area & would eventually chafe thru. I found a universal section (shown below) of hose with an array of bends in it & ordered it yesterday. Hopefully I can make it work. I know & can make this using 3 brass 90's & 4 sections of hose (I saw this on 1 of the Z forums), but that's a lot of clamps (which I consider potential failure points) and it's just plain ugly. Second, the hose is 7/16 & I can't find a clear filter with that nipple size. Anyone know of a clear filter with a 7/16 inlet/outlet? I'm ok with not adding a pre filter as it made it this far. The pump looks pretty old & I'm sure a replacement is in my future.

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I would go with a metal filter for under the car due to impact damage. I am sure NAPA or a tractor supply place would have what you want.

I would be very tempted to use an annealed copper tube to make all the bent part with rubber at the transitions, much as you have shown. If you use copper you can use Hussein’s trick of soldering a compression ring to the tubing to ensure the rubber hose cannot come off once it has a clamp on it. Using FI or Oetiker clamps on the tank and copper would work well. Using Cunifer as the metal tubing would be another material alternative for the metal line.

I would never use those type of common clamps on fuel line. They don’t apply even pressure and extrude they hose material through the slots. Using the backed fuel injection type clamps is a much better option and only nominally more expensive (if at all).
 
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kmead said:
I would go with a metal filter for under the car due to impact damage. I am sure NAPA or a tractor supply place would have what you want.

I would be very tempted to use an annealed copper tube to make all the bent part with rubber at the transitions, much as you have shown. If you use copper you can use Hussein’s trick of soldering a compression ring to the tubing to ensure the rubber hose cannot come off once it has a clamp on it. Using FI or Oetiker clamps on the tank and copper would work well. Using Cunifer as the metal tubing would be another material alternative for the metal line.

I would never use those type of common clamps on fuel line. They don’t apply even pressure and extrude they hose material through the slots. Using the backed fuel injection type clamps is a much better option and only nominally more expensive (if at all).
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I have FI clamps coming with the new hose. Diameter & length of the filter is a factor given the space I have to work with. I hit the copper tube with the flair tool to put a small bump on the ends to keep it from sliding off. The trouble I'm having is finding a filter with 7/16 nipples.
 
JKIDD said:
I have FI clamps coming with the new hose. Diameter & length of the filter is a factor given the space I have to work with. I hit the copper tube with the flair tool to put a small bump on the ends to keep it from sliding off. The trouble I'm having is finding a filter with 7/16 nipples.
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Are you sure it is 7/16ths hose? The X uses 12mm hose between the tank and the pump. If so the same prefilter we use on an X would work.

7/16th is not even a millimeter smaller in diameter than 12.

A 12mm inlet/outlet low pressure filter WIX 33299 or similar.
 
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