Does it makes sense to add a diesel fuel prefilter or second filter/water separator for South America?

[luthj]

Indeed, start small. The nice thing about aluminum angle, is that it can be easily cut with any wood saw that has a carbide blade. So most chop/miter saws. While I did a bit of welding to make my bracket, aluminum with a few 1/4-20 bolts would have been totally, fine. Just use nylock nuts and spring washers where appropriate. The filter base I linked above has a few threaded holes that make mounting to a bracket fairly painless.

 

[FreedomTraveler]

OutwestBound,

If you have the time and money all of the previous advise is good.

Other options I would point out;
-Buy where you see the trucks and buses buying fuel. ( Stations that turn over there fuel offen. )
-Try to keep your tank half full or better. ( less issues with settement pulled into pump / injectors. )
-Watch out for areas where it has been raining alot. ( Higher chance of getting water if the station is not well maintained. )
-Use a portable filter at each fill up. ( Mr. Funnel type product. )
-Monitor iOverlander for reports of bad fuel.

If your sticking to the paved roads you should never be in a possition of having to buy fuel from " A drum on the side of the road. " There are plenty of places to buy fuel, aside from local issues like Bolivia or the strike that occured in Brazil earlier this year. Again, monitor the local situation when you are there.

Safe travels,

 

[john.travel]

OutwestBound,
-Use a portable filter at each fill up. ( Mr. Funnel type product. )
-Monitor iOverlander for reports of bad fuel.
,

Thanks, good advice. I call this vehicle Cerdito or little pig because it's not to nimble. There will be exceptions but basically, I'll be on or very close to paved roads because this little motorhome just can't take the beating and/or go the places a smaller "van" or 4 x 4 can. We accepted that going in, because we need the space to keep working.

I have a Mr. Funnel that I planned on using for petrol, because I carry a Honda 2000 generator. I've never used the filer funnel, but it appears very slow. I wonder if I'd get strangled by waiting drivers if I tried to filter an entire diesel tank through one. Have you ever done this?

 

[luthj]

I personally would only filter fuel if the source is suspect. A filter won't stop water contamination. If the source is questionable, I would pump 300ml into a glass container, and view it. Contaminated diesel will usually be cloudy, have floating nasty, or visible sediment.

Particulate (especially larger particulate) will not cause damage usually. It may plug he fuel filter and cause performance issues or stalling. A fuel filter replacement will get you back on the road. Emulsified water can pass through the stock filter, and can cause injector and pump damage.

 

[john.travel]

I personally would only filter fuel if the source is suspect. A filter won't stop water contamination. If the source is questionable, I would pump 300ml into a glass container, and view it. Contaminated diesel will usually be cloudy, have floating nasty, or visible sediment.

Particulate (especially larger particulate) will not cause damage usually. It may plug he fuel filter and cause performance issues or stalling. A fuel filter replacement will get you back on the road. Emulsified water can pass through the stock filter, and can cause injector and pump damage.

I follow. I thought the OEM filter had a water separator, but just read the service manual description about the WIF sensor and how to drain the water of the filter. I'm astonished that there is no OEM water separation. Especially since I'll be down in South America skirting the winter on the south end, that's disconcerting! I spent a year in Alaska, so some of the advice on fuel procurement is known to me.

luthj, I followed the 2015 threat in which you learned about this issue and appreciate your sharing your solution on your build, which is Australia tested. If you could redo it, would you pick another filter? Some like the drain at the bottom like the P551001 separator has. I don't know if the clear bowl to see the fuel is essential.

 

[luthj]

I follow. I thought the OEM filter had a water separator, but just read the service manual description about the WIF sensor and how to drain the water of the filter. I'm astonished that there is no OEM water separation. Especially since I'll be down in South America skirting the winter on the south end, that's disconcerting! I spent a year in Alaska, so some of the advice on fuel procurement is known to me.

luthj, I followed the 2015 threat in which you learned about this issue and appreciate your sharing your solution on your build, which is Australia tested. If you could redo it, would you pick another filter? Some like the drain at the bottom like the P551001 separator has. I don't know if the clear bowl to see the fuel is essential.

The sprinters factory filter has a modest water separation feature. This is achieved with a coating on the filter media. It has limited capacity, especially for emulsified fuel. The in-tank electric pump tends to emulsify the fuel and water as it lifts it out of the tank.

If I were too do the filter over again, I would add a single donaldson filter (instead of two). I would use the P553207 filter (recommended above). This filter is 3 micron nominal, and has water separation media. It also has a drain fitting. The drain isn't strictly necessary. However, if you suspect fuel contamination, you can drain a bit easily to check. The donaldson filter will help to coalesce any emulsified water. If the filters water capacity is exceeded, the water (now coalesced into a solid mass) will flow to the factory filter. Once there it will trigger the water-in-fuel warning light.

DO NOT use any of the filters with a clear bowl. 99% of them cannot handle the 60PSI system pressure, and will break. I don't think a clear bowl is needed.

 

[john.travel]

The sprinters factory filter has a modest water separation feature. This is achieved with a coating on the filter media. It has limited capacity, especially for emulsified fuel. The in-tank electric pump tends to emulsify the fuel and water as it lifts it out of the tank.

If I were too do the filter over again, I would add a single donaldson filter (instead of two). I would use the P553207 filter (recommended above). This filter is 3 micron nominal, and has water separation media. It also has a drain fitting. The drain isn't strictly necessary. However, if you suspect fuel contamination, you can drain a bit easily to check. The donaldson filter will help to coalesce any emulsified water. If the filters water capacity is exceeded, the water (now coalesced into a solid mass) will flow to the factory filter. Once there it will trigger the water-in-fuel warning light.

DO NOT use any of the filters with a clear bowl. 99% of them cannot handle the 60PSI system pressure, and will break. I don't think a clear bowl is needed.

I just spent some time under the vehicle. Yours is lifted. Mine has many loom covered wires coming through that space, but there is enough slack to fashion them out of the way. While down there, I noticed a badly corroded metal clip on the rubber to metal fuel line, so you've helped me some more! This space looks ripe for a filter. I could easily see the OEM filter from below from here.

Did you just use self tapping screws or did you bolt the bracket on?

 

[luthj]

Did you just use self tapping screws or did you bolt the bracket on?

I used bolts. Self tapping screws would be adequate. As would 3/16 thread forming bolts.

 

[john.travel]

The sprinters factory filter has a modest water separation feature. This is achieved with a coating on the filter media. It has limited capacity, especially for emulsified fuel. The in-tank electric pump tends to emulsify the fuel and water as it lifts it out of the tank.

If I were too do the filter over again, I would add a single donaldson filter (instead of two). I would use the P553207 filter (recommended above). This filter is 3 micron nominal, and has water separation media. It also has a drain fitting. The drain isn't strictly necessary. However, if you suspect fuel contamination, you can drain a bit easily to check. The donaldson filter will help to coalesce any emulsified water. If the filters water capacity is exceeded, the water (now coalesced into a solid mass) will flow to the factory filter. Once there it will trigger the water-in-fuel warning light.

DO NOT use any of the filters with a clear bowl. 99% of them cannot handle the 60PSI system pressure, and will break. I don't think a clear bowl is needed.

Excellent explanation that I can easily understand. I owe you one. I'll study this over the weekend and scope it out, then make a parts list. My guess is it's $350 all in, for me, since I'll need to pay for some help. I'm not terribly concerned about whether I have to change it at 20,000 or 40,000 or 60,000, as long as it's reliable for the first 30,000 or so for this South American trip.

 

[john.travel]

I've decided to go with Luthj's full Monty! Thanks MWD for all your help! I'm doing a single P553207 filter/ water separator mounted in the location he selected. Please help with my parts list. Here's what I think I need, but I'm sketchy.

1 Donaldson P562261 head
2 Donaldson P553207 (one is a spare)
1 fabricated mounting bracket (I'll make this)
2 nylon lock bolts, nuts, lock washers for mounting bracket
? clamps (I assume 6 high quality of some kind and size)
? 1/2" NPT (hose barb fitting)(I assume either 2 or 4 maybe)
? 3/8" fuel hose (high quality)(? feet)

My OEM filter already has new stainless hose style clamps on it.

Thanks for any input.

John

 

[luthj]

Looks good. You want ~6ft of 3/8' fuel line (probably only need 3ft, so you can measure beforehand). Most auto parts stores will sell by the foot. 30R7 works, 30R9 type preferred. Ensure its rated for at least 60psi.

I would suggest fuel injection style clamps (not worm drive if possible). You can buy a whole kit on amazon with a large assortment for 16$ https://amzn.to/2zweNv2

Use brass or stainless barb fittings. One straight , one elbow would be my suggestion. The hose needs to be a firm fit on the barb. If you get a small amount of seepage, use two clamps. Use the following sealant on the threaded side of the barb fitting. Clean threads with solvent first. https://amzn.to/2re4iYI


Pay attention to the flow direction on the filter housing. There are two plastic lines in that area. One is return, one is feed. You want the feed line. The return runs to the cooler coils on the back of the tank, the feed goes directly to the sending unit on the top center of the fuel tank,

 

[john.travel]

After measuring and comparing your pictures luthj, it appears you vehicle is materially different than mine, in terms of the space available. Right where yours seems to be mounted, I have a 14-18" long, irregularly shaped, cylindrical device of some kind with a plastic cover aligned back to front. No idea what it is. Also, I have more cables running through having to do with the power in the motorhome, plus of course, I'm lower without a lift kit.

The only useable space I can see for a single filter appears to be 10-14" further forward towards the front. At this location, it's right were the fuel lines go from rubber to metal, so I "hope" I can do this using only rubber tubing.

When you did yours, did you cut into the metal lines?

 

[luthj]

I did not cut the metal lines (they may be plastic?)

Is it shaped kinda like a blimp? Then that tank is the vacuum reservoir (see diagram below. It is only installed on cab/chassis sprinters. No idea why, might be some regulatory thing. You can move it around, or just remove it and cap the line. It provides a reservoir of vacuum. If your engine were to stall, you would have enough reserve to apply the brakes with assist for 6-8 full pedal cycles. With the regular booster you have about 1-2 pedal cycles before you have no assist. Every other sprinter, including the 3500 series. (10klbs gross), operate just fine without that unit.

 

[john.travel]

Hey. Yes, that's the blimp ha ha. That thing isn't even in my 2006 service manual. I'm sure the German's had some American b.s. regulation involving motorhomes and punted. Who knows. Anyhow, I'm not comfortable removing the brake part, superfluous as it likely is.
I think those fuel lines are painted steel.

In only want to install one canister and there appears to be space, albeit tight and cluttered. I'll have to do more "figuring" but it appears I can hang the filter head from essentially the flat floor area behind the brake peddle, which is pretty open and clear it seams. I can see from under the hood where the steering wheel assembly penetrates the floor, so I'm pretty sure the area I can see from below is simply the cab floor behind the brake peddle. If I can fashion, or find a made bracket off something, that's generally square with about 1" width, and about 4" to 6" square or so, I don't know why I can't bolt it on from below and get a wrench on those bolt heads from above.

May be a little more of a PITA to service, but it actually may be up higher and with greater protection. Might work. I'll see tomorrow.

Thanks for your help.

 

[J!m]

Thanks. This issue has been on my mind as something to consider improving. As it stands now, I am able to change out a filter and bought 4-5 extras that I would carry. I've had some great posts here and I need to do my homework before responding with questions. My biggest concern is improving filtration and water separation WITHOUT increasing the probability of fuel system failure because I added something.

Adding a separator *before* the lift pump won't do any harm unless the flow rate is too low for the system.

Edit- reading other posts, it sounds as if the lift pump is in the tank like a BMW. In that case either ignore me (not a bad idea) or be sure the added hardware and plumbing are rated above the nominal operation pressure of the system. I like to use 10% as a guide, so if it runs at 50psi, make sure 55psi is comfortable for all the added bits.