Diesel primer on the fuel filter

[B52]

Common rail diesel Kia 2700, On morning starts engine idle ok for a minute, then the revs go down and engine stall.. unless I pump up the primer it will come good again for another minute or up the revs using the choke it will run ok in high revs. after a 15 minutes drive, idle become good and won't stall.

I replaced the fuel filter but still same issue remains.

Any advice appreciated.

[hinekadon]

sounds like injector to me to give you some idea how it works

[Rick]

Did you replace with a genuine fuel filter? If you are having to prime to get it right you have a leak somewhere that's allowing air to get into the fuel system, you may also have a blockage in the line from the tank.

[Thala Dan]

Not sure of your location, but.........if you're in a cold climate, make sure you're getting winter diesel.

Here, in a sub-alpine region, if you don't make sure you're using winter (what's flogged locally as "alpine" diesel) you can end up in trouble.

If I leave a container of summer diesel in the shed overnight at this time of year, in the morning it's about the consistency of peanut butter.

The fact that your vehicle comes good after a 15-minute warm-up possibly indicates that the fuel has warmed up and is flowing freely.

A bit more info here:

THE DAMAGES OF DIESEL IN COLD WEATHER



If you want to check your fuel.....drain some fuel into a glass jar....leave the jar out overnight in a shaded location (so it doesn't get the early morning sun).....hold the jar up to the light first thing early morning......if it's the wrong grade for this time of the year, the wax "crystals" will be clearly evident. If it's the correct grade of diesel, it should be absolutely clear and free of any "floaters".

[george65]

The above advice is sound in regards to gelling. If you start the thing up and drive it and it's good for the rest of the day, this could be your problem. You can add 5-10% Petrol to thin the Diesel out or something like Kero if you can find it a remotely reasonable price. If you are near an airport, AVTUR or JET-A1 will be a lot cheaper. I would also suggest throwing in a bit of 2 stroke to help with lubing the pump and injectors that may have been starved of fuel.

If gelling the fuel is your problem, a porta flood light sitting on the floor of the shed aimed up at the fuel tank will the fuel warm enough so it does not gel at night and avoids morning start issues. If your location is very cold you may have to put one under the engine as well to keep some warmth in the fuel filter.

If it is not a temp issue the next thing is to check the pickup in your tank. Also some IP's have a very fine mesh/ gauze strainer under the fuel inlet fitting. You unscrew the fitting and you might have to poke around with something fine and sharp to lift the gauze out. this is very common on the older Mechanical pumps but I have heard of some of the CR's having them too. They tend to catch different particles, sometimes strands and fibres that flake off the fuel filters. I had that problem myself where the fuel filters were shedding what I thought was dog hair. Luckily the fibers would catch rather than go through the IP but eventually they would block the fuel flow. I'd find them and wonder how the fk dog hair got in the fuel Tank. Other people I know ( how didn't even have pets!) had the same problem and it took a bit of figuring out.

It may also be a good idea to disconnect the main line at the fuel tank, disconnect the other end in the engine bay and blow high pressure air through it. I have done this on a few cars and the black sludge that came out that builds up from the diesel on the walls of the fuel line is amazing. If you can put a bit of hose over the nozzle of an engine cleaning gun and fill that with petrol and blow it down the fuel Pipe you may be amazed at what comes out.

There are a lot of fuel treatment Miracles in a bottle that are supposed to be cleaners. ALL of them ( and the OIL treatments) are all based on one thing... NAPTHA. Most of them are Naptha and a special ingredient like kero or diesel. Having no life and too much time, I have looked up all the MSDS sheets on these products and you find exactly the same thing. Main active ingrident, NAPTHA.

Naptha is also sold as Shellite ( lighter fluid) white gas, Coleman fuel, stove fuel and others.
You can but the stuff as naphtha or shellite at Bunnings for about $8-9 for a litre bottle which is a hell of a lot cheaper than the $14 you pay for 150Ml in a 200Ml bottle of fuel system cleaner.

Just chug half to a bottle of the stuff in the fuel tank and off you go. Have a spare fuel filter or 2 with you or get some of those inline disposable from super cheap and splice one of those in which isn't a bad idea anyway. The naptha will clean your fuel system, IP and injectors as much as any chemical cleaning will do. You may see some white smoke haze when doing this as the naptha will take out any water and clean other crap out as well. Some vehicles I have done this with smoke, most don't but it's nothing to worry about. I throw a bit of this from time to time in all the cars tanks to keep things clean and find it's well worth the minimal cost.

You can also throw a liter of this stuff in your engine before you change the oil and let the engine idle for a while ( best to do it from a cold start as naptha has a low boiling point and will evaporate quickly in a hot engine ) and let it idle 5-10 min. I like to let it sit there a while then drop the oil and change the filter. Again, if there is anything in there that can be removed without stripping the engine down, this will do it and is why it's in ALL the treatments in a bottle.

The next thing to do if these steps do not cure the problem would be get a small drum and run the fuel direct into the pump. If you still have the same problem you can be pretty sure your pump itself has an issue. Get ready for big $$ because diesel mechanics NEVER do anything like fix a broken spring or whatever it is always without question and fail a diagnosis that your pump is stuffed and needs a complete and full rebuild. Going to set you back $1500 to $6K. Check Fleabay here and US though. Sometimes they come up as new surplus stock cheap from jap importers.

Many Common rail engines have a lift pump and a high pressure pump. Late Range and Land rover diesels have 3 pumps. 2 Lifts and one pressure. A lift pump failing can cause problems like this and the engine to stutter when climbing hills on the highway for instance because the engine can't get enough fuel. Make sure ALL your pumps, especially the lift pumps are working. My Uncle had a failed Lift pump which I diagnosed when the Country dealers couldn't which Toymotor wanted $1500+ tax plus something stupid to fit the thing.
I got him a Bosch 044 off fleabay for $150 which turned out to be the exact same pump less the obstinate Toymotor fittings I bypassed with a bit of fuel line.
I think he and my Aunt are on there 3rd lap round the country now with the van on the back and hasn't had a problem yet although thought it a good idea to carry a spare anyway.

The 044's are a very common pump and fitted to everything from 911 Porches to landys as OEM pumps.

Good luck with it.

[B52]

Common rail diesel Kia 2700, On morning starts engine idle ok for a minute, then the revs go down and engine stall.. unless I pump up the primer it will come good again for another minute or up the revs using the choke it will run ok in high revs. after a 15 minutes drive, idle become good and won't stall.

I replaced the fuel filter but still same issue remains.

Any advice appreciated.

Further details. First thing in the morning before starting the engine if I press on the primer a few times I can hear as if air bubbles in the fuel tank,as I pump there's is more resistance until it won't go down, engine run for a minute or so OK then slow and stall unless I prime it again at which time the primer has no restrance until I push it down say 10 times it become hard again.

[george65]

Is the primer on a mechanical lift pump?
Not familiar with these things but on mercs and other cars I have had when they are there is also a one way valve in the pumps somewhere. Sounds like your pump may be shot and allowing the fuel to drain back. For it to do that though there would have to be an air leak in the system I'd think.

I would be checking all the soft line especially for cracks and leaks particularly on bends and where there are clamps and make sure they are all tight. Given the age of the vehicle, I'd probably be replacing all the soft line anyway and the clamps. Air leaks on Diesels can be next to impossible to find in fuel lines so easier just to replace it all. I always used that Braided clear Vinyl hose from bunnings so I could see any leaks. It's not great stuff but I replace it every year in my maintence schedule and it lasts that long so not a problem. Any good fuel line will do though and make sure you get either the spring clamps or the regular worm drive ones with the rolled edges so they don't cut into the line and do them up tight with a proper nut driver rather than a screwdriver which make great hand skewers on those clamps.

You should also look for signs of leakage and cracks in the hard pipe and check all the connections with that too.

I use regular PVC blue/ green cement as a sealant for pipe fittings. Slop it round and let it dry and give it another coat for good measure. I doubt it would do much for pressure leaks but for things like fuel lines that are under vacuum, I know it works perfectly for sealing joints. Don't even have to crack the joint, just clean it of any oil with degreaser and acetone and slop the stuff on.

[B52]

Primer and filter assembly is located on the opposite side of the fuel tank under the tray.

[Rick]

The primer might have a leaking valve allowing air into the fuel, i'd also try removing the fuel cap to see if there is pressure when you undo it, as a test remove the main fuel line inlet from the fuel filter, leave fuel cap off and blow around 20psi of air through the fuel line, you might have algae build in the tank or line causing a blockage.