Alternative IP pump priming methods

[3DB Senior Member Find all posts View Profile Close 3DB]

Use of biodiesel has caused my factory priming system that is built into my water/sediment trap to be rendered non-functional.

In my case, the non-return valves gummed up, so I had to remove one set and may need to remove the second.

Others I know of report that the bio has attacked the rubber diaphragm in the hand primer such that they have had to remove it to stop air leaks.

For the last 2 years I have had a (what now appears to be an imitation) Facet-brand electromagnetic pump installed in-line between the fuel tank and water trap. Most of the time it has no power applied and the IP is able to suck fuel through it. When I need to prime after a filter change or some other work, I connect the power and pump fuel through it until all air is purged back to the fuel tank through the IP return line.

Recently, I have had fuel starvation issues outlined in the recent thread titled "Engine fulling issues". I eventually put it down to a failure of the Facet pump causing the line to be blocked such that the IP could not draw fuel through it anymore.

I borrowed another genuine Facet pump and temporarily replaced my failed pump and had no problems for 2,000 km. I have now bought another knock-off ($17 on eBay) and immediately am having the same symptoms again, albeit not as severe.

I feel this method of priming is not sustainable, so am interested in what others have done to replace the factory primer on their vehicles. Johnnojack outline a vacuum method that is working for him in the aforementioned thread, but I am interested in whether anyone else has a good idea.

[Qwarla Senior Member Find all posts View Profile Close Qwarla]

Re: Alternative IP pump priming methods

I find that after doing a filter change there is no need to prime my system. Enough fuel remains in the IP to run the engine long enough to suck fuel up and fill the system.

Once on a trip, I ran the long range tank too low, and by the time I stopped, got out and changed the valves over the engine had stopped. 20 seconds or so on the starter soon fixed the problem.

The only time I have really had to prime the system is when I had the IP off to replace the front shaft seal.
That is via the manual plunger on the CAV filter I installed in place of the OEM filter after the rubber diaphram had split in the hand primer.

[3DB Senior Member Find all posts View Profile Close 3DB]

Re: Alternative IP pump priming methods

Thanks, Qwarla. I usually don't have to prime after a filter change either if I add fuel to the new filter before screwing it on. But anytime I muck around with the hoses - which is way too often at the moment - enough air gets in that it needs to be bled or it it just won't run properly.

The CAV primer is interesting. How long have you been running that? I assume the veg / bio hasn't caused it any dramas?

[Captaincademan Senior Member Find all posts View Profile Close Captaincademan]

Re: Alternative IP pump priming methods

I run a walbro pump on my landcruiser and a cheap-as-chips $20 pump on my mazda B2500. I removed the stock filter system on both cars and replaced it with a Cav style filter assembly with a glass bowl. Since doing so, I have had no filter / air issues at all. combined running distance since the change must be at least 150k. Walbro pump has been there for probably 5 years or more - never touched it. cheap pump on mazda was replaced just a month back, but as it turns out possibly unnecessarily.

Priming is as simple as turning the key to 'on'. I run the pumps on both vehicles off the fuel pump shut off valve circuit.

When changing filters I use a cut down juice bottle to slide under the filter assembly and then simply undo the bolt on top and drop the bowl and filter into the cut down bottle. wash the bowl and replace filter. turn key 'on' wait till the little pump catches up and your done.

very happy with my system. wouldn't change it as its so simple.

[3DB Senior Member Find all posts View Profile Close 3DB]

Re: Alternative IP pump priming methods

Thanks, Cade. Any chance you could provide a link to the CAV filter you use?
Does it have a hand primer?
Have you tested it to see if it still works lately?

I understand you have no need as your Walbro does it for you. I investigated these a couple of years ago and found them fairly expensive (I guess you get what you pay for e.g. my $17 fake Facet). I'd rather not have an electric pump at all if I can get away with it.

And why have you reversed the flow direction of the CAV? Does the standard setup push the fuel through the filter first, then into the glass bowl?

Is there any evidence of bio attack on any of the CAV parts?

[Qwarla Senior Member Find all posts View Profile Close Qwarla]

Re: Alternative IP pump priming methods

I went looking for pictures and most I found have diaphram primers. These last about 2 years before the biodiesel does it's job on the rubber.

My filter looks a little like this one.

The primer plunger is mounted different to this one. Mine faces to the front.
I have had this filter for prolly about 5 years now without any problems.

Only thing is you can not reverse the fuel flow because there are a couple of valves in the body.
There is a thread on here somewhere with a pic showing the paint or something coming off the bottom of the filter element, which can then pass straight out of the filter and down the fuel line.

[3DB Senior Member Find all posts View Profile Close 3DB]

Re: Alternative IP pump priming methods

Qwarla - that link you posted looks like a good one - robust. The primer seems similar to the one mounted on the side of the IP of my Merc, which seem to be very reliable. As you say, the most common one that comes up when you search for CAV filter-primers is the diaphragm style similar to what is on most Japanese vehicles.

So just to confirm - the plunger style you have has gone 5 years with no dramas? If so, I might try to locate something similar.

[3DB Senior Member Find all posts View Profile Close 3DB]

Re: Alternative IP pump priming methods

where does something like this fit into the equation?

[Johnnojack Senior Member Find all posts View Profile Close Johnnojack]

Re: Alternative IP pump priming methods

Ahha! That primer pump (Qwarlas) is similar to one I have on the shelf. It uses Orings as seals which I'm sure can be replaced cheaply. So if you wish to have a CAV type filter then that is the one to have. I don't like them (CAVs) myself as they have so many seals which can let air in. A spin-on is sooo much easier.

Don't know what that is DB but look up Mityvac, another option. However I think it is best to have something on board and fitted into the system rather than something you need to attach when you have trouble.
Both my diesel and oil systems are looped so I can't afford any small air leaks which would go unnoticed on a tank return system. However I can simply lift the bonnet, look and see at a glance if air is present, then remove it at the touch of a button in about a second.
Why do I loop the fuel? Stops oil returning to the diesel tank while flushing and viceversa.

[Tony From West Oz Vice Chairperson of WARFA Find all posts View Profile Close Tony From West Oz]

Re: Alternative IP pump priming methods

where does something like this fit into the equation?

3DB, that fits onto the lift pump on the side on a MB diesel injector pump (possibly other makes also) it doe not leak like the earlier plunger type which needs to be unscrewed to prime the IP. Just remove the old type and screw this one into the lift pump. Push down on the black knob to pump fuel, release to allow more fuel to be suckewd in, press again. East and clean way of priming one of these vehicles.

[Captaincademan Senior Member Find all posts View Profile Close Captaincademan]

Re: Alternative IP pump priming methods

3DB - no primer to the filter assembly. just a simple filter housing with glass bowl. http://www.ebay.com.au/itm/CAV-Secondary-Fuel-Filter-Housing-5836B100-/281222386411

reversed flow direction - read thread here

as the system is under slight positive pressure, there is no air leaks at all.

I check the housing everytime I change a filter for bug or other nasties, and nothing so far.

I buy either baldwin filters or sakura filters as I can get them for $6 each.

it truly is a trouble free system. (touchwood!)

[3DB Senior Member Find all posts View Profile Close 3DB]

Re: Alternative IP pump priming methods

Has anyone seen a CAV filter with plunger-type hand primer (similar to Qwarla's) for sale anywhere locally?

https://www.stardiesel.com/en/comple...6260-b195.html

They don't seem readily available. I guess I can try to get one from that Italian Star Diesel place.

Or do you reckon something like this could work in place of my Facet pump? I still have the air bleed screw on top of my existing water trap.

https://www.stardiesel.com/en/comple...be-m10x10.html

It is fitted with 10mm hose barbs by the looks, but seem like you could easily get some 8mm versions to swap out.

I also briefly considered these boat-style primers. This one is polyurethane - how would it handle bio?

https://www.stardiesel.com/en/rubber...9001-088a.html

[Tony From West Oz Vice Chairperson of WARFA Find all posts View Profile Close Tony From West Oz]

Re: Alternative IP pump priming methods

I also briefly considered these boat-style primers. This one is polyurethane - how would it handle bio?

https://www.stardiesel.com/en/rubber...9001-088a.html

I had one of the primer bulbs before the fuel pump in my C250 and it worked well. The only trouble with it is that the fuel pump sucks the fuel very well and it collapses the bulb. After a few months, the bulb is flat (actually concave on one side convex on the other) and cannot be used.

In another thread here a member wrote about having to remove the one way valves on their CAV (?) filter to remove a flow restriction.



If choosing one of these, place it in the return line. It will work just as well and not be sucked flat.

[smithw Senior Member Find all posts View Profile Close smithw]

Re: Alternative IP pump priming methods

Peugeot comes out of the factory with those fuel priming bulbs, the bio will eventually eat is way through. I replaced mine twice, a both times the bulb failed enough to stop the engine. I would not recommend them for bio, and I replace the bulb with a facet pump I have had no further problems

[3DB Senior Member Find all posts View Profile Close 3DB]

Re: Alternative IP pump priming methods

No easy options eh?

I actually tightened up the hose barbs on my fake Facet and it is working now, so I might have jumped the gun a bit. The last one went for 2 years before it karked it, so may be I should just buy another $17 one and keep it in the vehicle as a spare for when this one lets go.

Not great in terms of resource efficiency / waste.