2008 Patrol Diesel Pump not priming

[poddy]

It's a 2008 3.0 CRD

When starting the car, I turn the key, wait for the glow plug light to go out, then turn it all the way to crank. The engine turns over for a bit (4-5 seconds) and then it starts. It's a very lazy start, but it does start.

As opposed to what it should do - start right up - no excuses.

My assumption is that the diesel pump isn't priming prior to start, so it takes a few turns of the engine to get the fuel pump to build up enough pressure to ignite - but the fuel pump works, because once the car starts, it runs fine.

I am looking for pointers to what I should not miss, perhaps there is something obvious I am missing. Any info is greatly appreciated.

EDIT:
- when I prime the fuel with the hand pump just above the fuel filter, it gets hard on the third/fourth squeeze. If I leave it then, and don't start the engine, it goes soft again. And then, if I start pumping again, it doesn't get hard anymore, no matter how much I pump.
- I replaced all glow plugs, and tested voltage to the glow plug rail, which appears to be working fine. New glow plugs didn'tmake any difference.
- I ordered the replacement fuel pressure relief valve and will post an update once that is changed. (That was it, see below. )
- I have a injector leak back test scheduled for the weekend. - didn't end up doing this.

RESOLUTION: Fuel Pressure Relief Valve - replacing this $85 part resolved my long crank before start.

[PeeBee]

Check glow plugs, sounds more like that than fuel priming to me. The fuel will ignite in the cylinder based on compression and droplet size, when you say fuel pump are you referring to a lift pump or the injection pump? The lift pump is fitted between the fuel tank and the injector pump to provide a positive pressure to the injection pump inlet. is your vehicle a common rail diesel?

[poddy]

are you referring to a lift pump or the injection pump? The lift pump is fitted between the fuel tank and the injector pump to provide a positive pressure to the injection pump inlet. is your vehicle a common rail diesel?

Thank you, I found this very educative. And yes it is common rail. I went back and edited my original post after your query.

[Fireblade]

id be thinking glow plug relay (near the drivers right knee abour the fuse box)
or fuel pressure relief valve it might not be close allowing to build pressure, how does it start if you have it running then turn it off and then 10 seconds later start it back up? does it take awhile to start or does it go good?

check oul my thread about testint and replacing the valve
http://www.nissanpatrol.com.au/forum...and-replacment

[poddy]

id be thinking glow plug relay (near the drivers right knee abour the fuse box)
or fuel pressure relief valve it might not be close allowing to build pressure, how does it start if you have it running then turn it off and then 10 seconds later start it back up? does it take awhile to start or does it go good?

check oul my thread about testint and replacing the valve
http://www.nissanpatrol.com.au/forum...and-replacment

Thank you this is very informative. Actually, cranking within 10seconds of shutting down a warmed up engine takes far less time, about 3 seconds. But it still isn't starting as it should. There is definitely a problem. But yes, when the engine is warmed up, I shut it, and then start it up, it does take considerably less time.

[the evil twin]

Agree with the other guys... unlikely to be the pump on a CRD, possible but unlikely.

Check the glow plugs and operation first then move onto relief valve etc

[poddy]

Agree with the other guys... unlikely to be the pump on a CRD, possible but unlikely.

Check the glow plugs and operation first then move onto relief valve etc

Already found 1 plug that is cactus. 2 are ok and 1 is unknown. Di CRD diesel pumps hace a rep of being solid? (Yep, I'm new here)

[poddy]

I pulled the glow plugs out today and measuerd their resistance.
1 has 10 mega ohm resistance, 2 has 0.8 ohm, 3 has 1 ohm and 4 I wasn't able to remove. PSX_20201121_213609.jpg
I also found a 10A fuse missing, the plastic cover just read "Glow"; It was in one of the fuse boxes in the engine bay. I re-installed the fuse - it didn't blow since.

I didn't check the relay. I've been trying to look up how to check a relay, but I am still a bit unclear - how do you guys check the relay?

Overall, my long crank before engine fires up remains unresolved. But I did order a set of new glow plugs NGK Y538J.

[poddy]

This is the one with a redistance of 10.52 mega ohm.
PSX_20201121_211810.jpg

[Bidja]

Question is at warm start up, does it stiil need to crank for several seconds before she starts up.

Understand that CRD will not start until all injectors obtain a even fuel pressure of approx 140MPa (20,000psi). This is why it can take several seconds of cranking to fire up because all have to come up to pressure. Need for an SME to conduct a return fuel leaking test.

May need to consider this.