Pictures of your twin filter installation please

[Tillsbury]

Ok, so now I have one wall of the engine room clear for putting my new pair of racor filters into the fuel system. Does anyone have any suggestions as to layouts, schematics, thoughts about electric priming pumps, that sort of thing? I would like to get the plan fixed in my head before starting work, so it ends up as neat an installation as possible.

Advice about mistakes made also welcome, and how you would ideally like it.

Primary objective is to have the ability to clean/change filters on the go, of course. Any other things I should be considering?

[Q Xopa]

Originally Posted by Tillsbury

Ok, so now I have one wall of the engine room clear for putting my new pair of racor filters into the fuel system. Does anyone have any suggestions as to layouts, schematics, thoughts about electric priming pumps, that sort of thing? I would like to get the plan fixed in my head before starting work, so it ends up as neat an installation as possible.

Advice about mistakes made also welcome, and how you would ideally like it.

Primary objective is to have the ability to clean/change filters on the go, of course. Any other things I should be considering?

Schematic, sorry cant help you.You're right though I should do one.
A few thoughts if I may.
I am just going through this process myself.
I assume you are talking about the Racor 500 Dual Turbine Filter assembly with the selector valve and optional vacuum gauge?

Not cheap at around $1,000. But I sprung for one. I havent fitted it yet as my refit is not quite upto that point yet.

No doubt they are very good and will do what we want. But having given the matter some thought since, I probably wouldn't have shelled out and simply made my own.

The gist is, with the 3 way selector, run one at a time. When one clogs, or vacuum gauge if fitted is high, select the other unused clean filter. Then clean or replace the other whilst still running.

So this can easily done with with 2 single filters (Racors or whatever), with a 'Y' or 'T' and on/off valves on both the the inlet and outlet.

Admittedly the off the shelf ready made Racor Twin is done nicely. But I reckon I could do some nice plumbing for substantially less.

The single Racor 500 is around $200. A lot less for a ebay knock off. So for 2 at $400 I still have a bit to play with.

Circling back to your comment about having a pump to bleed the system. The above filters are meant to work on 'vacuum' from the motor pump sucking.

So really you cant use a pump downstream of the above filter setup.

So really this is a 3 filter fuel system.

Most people who have a pump for priming, and more commonly polishing have it set up on a seperate filter. All best done using a seprate, ideally lower tank pick up. So any sludge is sent through the polish filter.

Ideally a good pressure pump flow to turn over the tank volume and with the tank return so it can wash off and stir up sludge, possibly the lowest tank points.

I have seen people power the pump with the motor 'ignition' switch. So when the motor runs and the Alternator is providing plenty of power.

Maybe you want more control and have a seperate switch. Always the chance of forgetting to switch it on, or off. Sounds like something I would do.

Fuel bleed loop from pressure pump via 'pressure' filter, 'T'ing into the engine fuel supply line upstream of the filter with a valve.

Header tanks, if applicable, obvoiusly need some consideration how they fit into the system too.

Good luck.

[Tillsbury]

Thanks for that. No, I don’t have a kit, I have two individual ones. So I’m open to all options of valves and pumps. I’m guessing that a centrifugal pump mounted low enough would just be free-running when off, so it just needs a switch to have it running when priming is necessary (for the filters or the engine itself). But I’m not 100% sure, hence this question.

[Madehn]

i did exactly what you are doing by putting together a manifold with 3 way valves - made an aluminum housing for it etc-- looked ok -- worked ok -- couple of lessons- i put an electric pump that id could use as a source for fuel or i could just run the normal straight line to the tank- plumbed it that way so that under normal conditions i was not having to pull fuel through the pump. i can tell you that the thing was a real PITA to build and then make absolutely leak free-- i used a lot of short lenghts of hose between the three way valves of which there were three - so figure 14 or more hose connections-- like i said when it was done it worked but i also found out that even though i used the best hose i could find and the best hose clamps money could buy that i later had issues with air leaking in as the hoses aged etc. Eventually i found a brand new twin racor unit at a WM that was remodeling and clearing out all their old stock- got it for $300 and i took my unit off. if i was going to do it again, i would use pipe fittings and as few hoses as possible. my home made usit cast me around $500 bucks including the two racor units, valves, clamps, vacumn gauge etc and that didnt include the time.

[Madehn]

you can get an inexpensive pump that can handle diesel at almost any auto parts store- i have mine set up with an on / off / momentary on switch. Normally it is off-- if i ever have problems with the engine driven fuel pump i can switch the aux to "on" the momentary on switch is down by my filters so that i can fill the filter bowls when changing them and avoid the mess of bleeding the injectors-- works well so far, One caveat- when some engine driven pumps fail, there is a failure mode where diesel starts being leaked into the crankcase which is all bad-- would not want to keep running with your Aux pump in that type of condition.

[a64pilot]

I bought the factory one, have never had a use for it yet.
You don’t have to, if I were to do it again, I’d simply plumb in two individual filters, you don’t need a three way valve. You only need two shut off valves, you can either put them before or after the filters. Doesn’t matter, just turn on the one you want to draw fuel through, or both if you wanted to.

Every normal electric fuel pump I know fuel can be drawn through the pump without it running, just plumb it in before the T that splits to the two filters, so that it can fill either empty filter.
I keep meaning to install one, just haven’t done it yet myself.
I’d connect it electrically to the ignition switch so that it can’t be left on or knocked on by mistake without the engine running or at least the “ignition” being on.

[Madehn]

i like A64's solution a whole lot better than what i did-- simpler cheaper and gets the same job done- wish i had thought of it-- too soon old too late wise-- you can put the vacumn gauge if you decide to use one after the filters - tee d into the common supply line-- Darn why didnt i think my way through this- making the other one with all of the valves and everything took hours.

[Tillsbury]

Well that’s kind of exactly why I asked the question before buying loads of fittings

With two shut offs before the filters, though, you can’t replace one with the engine running surely? Wouldn’t I need shut offs after the filters too? In which case wouldn’t just two Y-valves be better (one before, one after)

[Q Xopa]

Originally Posted by Tillsbury

Well that’s kind of exactly why I asked the question before buying loads of fittings

With two shut offs before the filters, though, you can’t replace one with the engine running surely? Wouldn’t I need shut offs after the filters too? In which case wouldn’t just two Y-valves be better (one before, one after)

Yes true to all of what you said.

You can have 2 x single valves, or a 3 way valve.

Single on/ off valves are much easier and chesper to find.

You can have one before and one after on each but it is uneccessary. One in either has shut that parallel path.

Actually the Racor one is a 4 way selector-
Open #1
Open #2
Both Open and
Both Closed

This makes it a bit special, ie hard to get replacement parts and pricey.

Yes good comment about hoses. If you want to improve on barbs and hose clamps you could go to the trouble of getting your local hose guy and get proper hoses with fittings. Even better if you can get solid pipes made like the Racor units have.

Re a pump before the filters. If Im not mistaken those filters are meant to operate as vacuum filters. Hence the vacuum gauge clogging indicator. But they can probably operate ok under pressure.

Re the vacuum gauges I like the ones with the maximum indicator that gets pushed to its highest reading by the normal instant needle.

[Tillsbury]

If you only have a valve before and not after, you can’t remove a filter while the engine is running, surely?

[Q Xopa]

Originally Posted by Tillsbury

If you only have a valve before and not after, you can’t remove a filter while the engine is running, surely?

It should be ok. I havent actually tried it, but there should be no flow through that path.

It's just like an electral circuit switch. You only need one switch to open and close the flow, not one either side of the load.

I would give it a little test run first. If it didnt work move to plan B and put another couple of valves in. Or you could just do it from the outset.

However unless you can fill the filter assy up with fuel again after replacing or cleaning the element you would introduce a 'slug' of air when you opened that tap again. Depending on the amount of air if the engine was running it might just 'hickup' or it might stop.

I guess if it was a pressure filter arrangement you could open the inlet valve slowly with the filter outlet loose until the air was all pushed out. Then open the filter outlet valve.

But normally those filters are meant to be vacuum, not pressure.

If you are going to this trouble I would also include another seperate filter or seperatable with Ts and valves as a Polishing circuit.

So ideally-
twin parallel individually isloatable Vacuum filters, and
An additional pressure filter for polishing and bleeding.

[Q Xopa]

Originally Posted by Q Xopa

It should be ok. I havent actually tried it, but there should be no flow through that path.

It's just like an electral circuit switch. You only need one switch to open and close the flow, not one either side of the load.

I would give it a little test run first. If it didnt work move to plan B and put another couple of valves in. Or you could just do it from the outset.

However unless you can fill the filter assy up with fuel again after replacing or cleaning the element you would introduce a 'slug' of air when you opened that tap again. Depending on the amount of air if the engine was running it might just 'hickup' or it might stop.

I guess if it was a pressure filter arrangement you could open the inlet valve slowly with the filter outlet loose until the air was all pushed out. Then open the filter outlet valve.

But normally those filters are meant to be vacuum, not pressure.

If you are going to this trouble I would also include another seperate filter or seperatable with Ts and valves as a Polishing circuit.

So ideally-
twin parallel individually isloatable Vacuum filters, and
An additional pressure filter for polishing and bleeding.

This guy talks about his system he made up-
https://youtu.be/EaI4ndtzvC4

[Jansen2]

Since I took this picture I have added an electric fuel pump and a meter measuring the pressure drop over the active filter.

[mickand]

Found a pair of 1000's with a vacuum gauge on Ebay for $315

[a64pilot]

Originally Posted by Tillsbury

Well that’s kind of exactly why I asked the question before buying loads of fittings

With two shut offs before the filters, though, you can’t replace one with the engine running surely? Wouldn’t I need shut offs after the filters too? In which case wouldn’t just two Y-valves be better (one before, one after)

That is correct to actually replace one with the engine running you will need two valves on each filter, one before and one after so that the filter can be isolated.
However I don’t know why you would want to replace one with the engine running, I don’t think you can even do that with the factory dual filter set up.

If I were to clog a filter coming into a channel etc., I think I would just open the other one, so the engine would draw through both, if one were completely clogged no issue, it’s just going to draw through the other one.
The factory dual set up allows either filter or both, or all off, you can duplicate that with just two valves and two T’s if you desire.