Difficulty priming diesel engine

alanmc

I'm about ready to put my boot through this sodding diesel car.

Right, rant over. I started off the day replacing the air filter and fuel filter in my commuting workhorse.

It's a 04 Peugeot 407 with the 1.6 HDi (DV6) engine (110bhp version).

The physical aspect of the job went well, but I can't seem to prime the fuel lines. I've pumped the priming bulb until my arms are about to fall off, but the filter (which is a sealed unit) doesn't seem to be filling up and the bulb remains soft. Intermittently, I've tried starting the car. The odd time it catches and runs for maybe 5 to 10 seconds, but then dies. So, some diesel must be getting through.

I think the valve in the priming bulb might be stuck open. Is there another way to prime the fuel system? Has anybody else solved a similar problem?

Anyway, tomorrow, I'm going to try manually filling the filter with diesel and see if that makes a difference.

One more thing crossed my mind just there: Does the ignition need to be on to prime successfully? I CBA to go out and check now.

McP2011

Take of the pipe that goes into the fuel filter housing (should be coming from the hand primer)...cover the end of it with your finger and then start pumping..youll probably have to keep releasing your finger of the end of the pipe...put it back on the fuel filter housing when the diesel starts flowing.

alanmc

McP2011 wrote: »

Take of the pipe that goes into the fuel filter housing (should be coming from the hand primer)...cover the end of it with your finger and then start pumping..youll probably have to keep releasing your finger of the end of the pipe...put it back on the fuel filter housing when the diesel starts flowing.

Cheers man. I'll give that a go. I assume I'll have to fill the filter by hand using this method as well.

barneygumble99

yeah you need to fill the filter to the top and it should start then. i usually disconnect the outlet pipe from filter and fill it through there with a separate pipe or large syringe. it should start then. those primimg pumps are a lottery at the best of times. shouldnt matter if ignition is on or off on most cars. vw have a pump fitted in the tank that pumps diesel when u turn ignition on.

McP2011

No you wont have to fill up the filter housing by hand...when you do what i said to get the diesel coming just put the pipe back on the housing and keep pumping the primer it will fill it the filter...the primer will get a wee bit hard when its completly full.

couldntthink

Filling the filter may not work if you've been trying for so long. By now every part of the system probably has air in it. As stated earlier these can be a testing primer at times. Try what McP2011 said first, but have patience as it may take a while. You could try pushing fuel through with compressed air from the tank, if all else fails. I had one a few months back that had major work done and whole system was airlocked. Only way I could get it going was to pull fuel through the system at the return pipe using an electric pump.

Tropheus

I had the same problem on my Audi Allroad a few weeks ago. I changed the fuel filter (which I've done many times before), but it just wouldn't start.

I had the car up on ramps when I tried to start it first which probably contributed to the problem. I gave up after about 20 mins when the battery was knackered.

I left it on the battery charger over night to make sure the batter was fully charged. I find with diesels, even though there appears to be enough juice in the battery to turn the engine, there's just not enough to get it started.

The next morning with a full battery charge, it eventually started after about half a dozen lengthy turns.

I don't know what happened this time around as I always fill the filter with diesel before connecting hoses.

Tropheus

I had the same problem on my Audi Allroad a few weeks ago. I changed the fuel filter (which I've done many times before), but it just wouldn't start.

I had the car up on ramps when I tried to start it first which probably contributed to the problem. I gave up after about 20 mins when the battery was knackered.

I left it on the battery charger over night to make sure the batter was fully charged. I find with diesels, even though there appears to be enough juice in the battery to turn the engine, there's just not enough to get it started.

The next morning with a full battery charge, it eventually started after about half a dozen lengthy turns.

I don't know what happened this time around as I always fill the filter with diesel before connecting hoses.

alanmc

I got it sorted. I got a guy out who primed the system with a hand pump. It's a 5 minute job once you have the equipment. The battery was in good shape and it started up after just a few cranks once there was diesel in the system.

Thanks for the help guys. I tried the "thumb over the hose" method, but I was getting no fuel through at all. I think the bulbs valve is well and truly knackered.

Just glad I got the old workhorse back on the road. I had to use the toy today for the commute .... which was not an unpleasant experience