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Pre pump fuel filters


24OZ

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Guys,

 

I have just bought a new fuel pump and I would like to purchase a decent filter before the pump. My pump is located at the rear behind the fuel tank and I would like to fit a largish cannister type filter before the pump in order to help with fuel starvation, I have a 240Z tank.

 

Reading up the archives people have recommended the FRAM one P/N FRM-HPG1 . Is this a pre fuel filter pump and does it use barbed connectors?

 

What are peoples thoughts if I just used a 280ZX or 300ZX TT filter as a pre pump filter instead, will they work as a pre pump filter? I read that there is a difference between filters designed to be fitted before the pump and filters after the pump

 

Thanks for any advice, words of wisdom etc..

 

BTW- I do not want to fit a surge tank just yet, but may be one of my options in the future.

 

240Z Turbo (L28ET)

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I am not sure what the difference between a pre pump and post pump filter would be. I thought they were all suppose to be prepump.

 

All you really want in the prepump filter is a high flow capacity. That means a paper or metal screen type (and not the sintered bronze or what ever it is).

 

I just went through this on my 240 last night. I had bought a large canister type filter but similar to the pic below but couldn't figure out a clean way to mount it. (By the way, how did you get a fuel pump BEHIND a 240 tank?)

 

sum-g1501.jpg

 

I ended up just getting an in line unit at WalMart. It is a fram, I think FG3 with 3/8" barb inlet and outlet. Less than $4. The Fram unit for the LS Camaro's looked like it would work also. Only $10.

 

Your other option is to just thumb through one the many fuel filters on Summit's site and

 

http://store.summitracing.com/egnsearch.asp?N=700+4294925239+115+4294839051&NeXID=5

 

I don't think the filter on the pump inlet side will do anything to help with fuel starvation. If you uncover the in tank inlet you are still going to suck a slug of air into the filter. The only way to get the air out of filter is to run it through the pump.

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Thanks for your input. I did some more investigating on the Fram i posted above and the Summit site lists it for carburated vehicles so i am now thinking of not using it.

 

By behind the fuel tank, I meant in front of. I have it bolted on the diff cross member.

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Thanks for your input. I did some more investigating on the Fram i posted above and the Summit site lists it for carburated vehicles so i am now thinking of not using it.

 

By behind the fuel tank, I meant in front of. I have it bolted on the diff cross member.

 

That is pretty much where I bolted my fuel pump. Got the bottom nice and low, but above the control arm inner pivot. I wanted to put in that big canister type filter, but keeping that low also would have required running some type of mount down from the back deck. Decided to go in line just to make some progress.

 

BTW, I don't know that there is any real difference between a FI and carb'd filter. Especially on the inlet side of the pump. Maybe someone will correct me if I am wrong.

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Guys,

 

I have just bought a new fuel pump and I would like to purchase a decent filter before the pump. My pump is located at the rear behind the fuel tank and I would like to fit a largish cannister type filter before the pump in order to help with fuel starvation, I have a 240Z tank.

 

Reading up the archives people have recommended the FRAM one P/N FRM-HPG1 . Is this a pre fuel filter pump and does it use barbed connectors?

 

What are peoples thoughts if I just used a 280ZX or 300ZX TT filter as a pre pump filter instead, will they work as a pre pump filter? I read that there is a difference between filters designed to be fitted before the pump and filters after the pump

 

Thanks for any advice, words of wisdom etc..

 

BTW- I do not want to fit a surge tank just yet, but may be one of my options in the future.

 

240Z Turbo (L28ET)

 

Most OE filters are post pump, though the OE Datsun/Hitachi EFI pump does have an inlet “screen” to catch large particulate and old rusty tanks can and do regularly clog those inlet screens… I “sort of” like the idea of a pre pump filter for protecting the pump against the occasional debris, but the inlet side of the pump is sensitive to restriction and needs a steady consistent flow of fuel to operate at peak efficiency, so maybe it isn’t such a good idea. Also, keep in mind that many OE pumps last 100,000, 200,000+ miles without a pre pump filter, only an inlet “screen” and personally, by 100,000 miles, I feel the pump becomes a “consumable part” and probably should be replaced anyhow. …

 

I am not sure what the difference between a pre pump and post pump filter would be. I thought they were all suppose to be prepump....

 

I just went through this on my 240 last night. I had bought a large canister type filter but similar to the pic below but couldn't figure out a clean way to mount it. (By the way, how did you get a fuel pump BEHIND a 240 tank?)

 

sum-g1501.jpg

 

I ended up just getting an in line unit at WalMart. It is a fram, I think FG3 with 3/8" barb inlet and outlet. Less than $4. The Fram unit for the LS Camaro's looked like it would work also. Only $10.

 

Your other option is to just thumb through one the many fuel filters on Summit's site and

 

http://store.summitracing.com/egnsearch.asp?N=700+4294925239+115+4294839051&NeXID=5

 

I don't think the filter on the pump inlet side will do anything to help with fuel starvation. If you uncover the in tank inlet you are still going to suck a slug of air into the filter. The only way to get the air out of filter is to run it through the pump.

 

 

As for that chrome red topped filter, throw it away. I tried one on the race car, (I bought the same one through Summit Racing), and it leaked terribly as the chrome canister would not seal properly to the square rubber O-ring in the lid. I tried another O-ring, even tried to “clean up” the roughness at the sealing edge of the chrome canister, but could not get the “roughness” out and it still puked gas. After wasting more time on it that it was worth originally, I eventually threw it away and spent the money on a Mallory Billet Aluminum version and haven’t looked back.

 

http://store.summitracing.com/partdetail.asp?autofilter=1&part=MAA%2D3160&N=700+115&autoview=sku

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I don't think the filter on the pump inlet side will do anything to help with fuel starvation. If you uncover the in tank inlet you are still going to suck a slug of air into the filter. The only way to get the air out of filter is to run it through the pump.

 

Actually, if the filter is oriented correctly, with a tube to the bottom of the filter element for the pickup, and the inlet side just dumping fuel to the area circumfrentially around the filter...any 'sucked air' would remain at the top of the filter housing...

 

With slight modifications such as running the return line into the top of the filter, and then back out to the tank, any sucked air would be bled back to the tank... it's basically a switl pot/surge tank at that point, but modification of the Fram filter to that configuration is VERY easy with some barbed fittings, a drill and a tap...

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Thank you all for the very helpful comments.

 

I would be interested to hear what you guys think of this integrated filter and surge tank, could it be the answer to my problems? http://cgi.ebay.co.uk/FUEL-SWIRL-POT-FILTER-ESCORT-MK1-MK2-RS-TURBO-COSWORTH_W0QQitemZ150025311376QQihZ005QQcategoryZ21654QQrdZ1QQssPageNameZWD1VQQcmdZViewItem

 

Thanks.

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The pre-pump filter is just to protect the pump. If you have a tank with some crud left in it, it is very important as you can damage your pump without a pre-pump filter. I use one of those 3/8" clear plastic ones. I think they are 10 micron, which is fine on the inlet of the pump. I like them because they are cheap, and they are clear, so you can see how much crud has accumulated in them. If you are on a trip, and need a replacement, you can get a new one at any parts store. Don't use a clear glass one under the car for obvious reasons.

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Everything I read says the filter is suppose to be on the inlet side of the pump. Mallory says you must use a minimum of 40 micron filter before their pumps, althought they do say it is to prevent crud from jamming the georotor they use. Even Grumpyvette says inlet. I often thought the outlet would be better because you would suffer less headloss on the positive pressure side than the suction side. But all the manufactures have them on the inlet.

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I got ya Tony thanks!

 

Just for interest.

 

I went to my local motor factors today looking for a large pre filter and i didnt find what i was after but found these interesting after pump filters, at least they must be.

 

They are big mamas, the one on the left is for a BMW Z3 3.2 and the other is for an AUDI TT.

 

www.xiotis.com/filter.JPG

 

www.xiotis.com/filter1.JPG

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