Have to prime fuel after a few days, TD42

[Winnie]

Hi,

I have a TD42 GQ and if I leave it for a couple of weeks, when I go to start it I will have to prime the fuel system to get it to start. So I think air is getting in somewhere? Once I have primed it, I won't have to do it again for a while and if I drive often I never have to do it, but my car can go a while without being driven.

[BigRAWesty]

How does it go when you turn the key off?
Does it stutter a bit before stopping or cut off in a couple rotations?

I'm thinking fuel valve solenoid.

[Winnie]

Nah cuts out straight away. How could the solenoid let air in?

[threedogs]

Fuel lines may be perished, I remember a thread where fuel line was cut in rear wheel arch on top of chassis .
Might have even been MR
Cheap enough to replace all fuel lines with the Simmo coming up, don't want to break down eh

[BigRAWesty]

Nah cuts out straight away. How could the solenoid let air in?

I was thinking it could be syphoning back to tank..

[Winnie]

Fuel lines may be perished, I remember a thread where fuel line was cut in rear wheel arch on top of chassis .
Might have even been MR
Cheap enough to replace all fuel lines with the Simmo coming up, don't want to break down eh

Yeah you're right John, probably worth doing anyway even if they are not the problem. It sure won't hurt to do.

[nissannewby]

Sounds like air mate. The seals in the primer pump can also be the problem. Just replace all your rubber lines and see how you go. If it still does it then I would be looking at the primer.

It won't be the solenoid even if it was playing up only way the fuel will drop as such is due to air.

[Sir Roofy]

try the rubber seal in the filter housing if its not sealing it can let
the finest bit of air into the filter if you have a glass bowl might be the o
ring doing the same

[Winnie]

Thanks guys I will have a play on the weekend. I just went to start it after driving it on Saturday and it would not go so it is happening faster.

[Woof]

Mine has been doing this on and off for years, maybe time to look at it as well

[FNQGU]

Has to be air getting in I agree. It isn't simply one of the hose clamps being loose is it? The hose clamp on the incoming side of the fuel filter or underneath the vehicle at the back of the lift pump?

I happen to have an in-line plastic fuel filter between my main tank and the lift pump and when I change the filter out, I risk getting an air bubble into the lines. If not careful it can stall the engine and mean I have to bleed the system. You could change out your whole fuel line system if you so feel inclined, or it is in poor condition, but the problem is most likely occurring at a connection for my money.

If you disconnect your outgoing hose from your fuel filter and pump the primer a few times, does it blow out frothy fuel or a nice solid stream?

[MudRunnerTD]

I chased this problem for 6 months Winnie and was ready to rebuild the fuel pump on the GUIV. I replaced the primer pump and it was not the cause so have a spare here you cold try mate, if I remember I will bring it to ABs. Mine ended up being a stone on top of the right side rear spring tower wore a hole through the steal fuel line and bled air in. I cut it out and swapped that section for rubber fuel line and never had the problem again. Bloody freaky it was!!!

I would have been shattered if I'd blown $2000 to rebuild the perfectly good pump and still have the problem!!

[Antpenny]

I had the same problem and found the fuel lines either side of the filter were slightly perished letting air in. Just swapped them out and problem solved!

[threedogs]

Yeah you're right John, probably worth doing anyway even if they are not the problem. It sure won't hurt to do.
Cheap enough to do for peace of mind and one less thing to worry about
It was MR that had the problem but all sorted now.

[love ke70]

If you fit a lift pump you will solve the issue, but it will also weep where it is leaking, so should identify the issue too, unless the issue is pre lift pump.

Cheers, Andy

[Winnie]

Sorry mate, what is a lift pump?

[nissannewby]

Sorry mate, what is a lift pump?

It's quite common to install a low psi high flow 12v pump in the main fuel line (something like a carter 4600hp). What this does is takes the strain off your ip as it now has a nice constant supply of fuel ready and waiting. Have a small amount of pressure can add a touch of timing and sometimes is noticed in response times.

[Winnie]

Is it worth it for my setup? I mean disregarding my current air leak problem.

[love ke70]

What is your setup?
I put one on long ago and highly recommend it..

[Winnie]

11mm pump (it's worn out and needs rebuilding at some stage in the not so distant future), GTX2863R with Cross Country top mount intercooler.
120kW at 16psi.

[threedogs]

Big Fletch just fitted a Carter and only has good things to say about it.
Its in his build thread on his new Patrol

[love ke70]

I am running a Walbro FRB-51
I have had it since late 2010 and its been fully submerged many times, including the time I drowned the ute to the rear view mirror without issue.

Its running is in-audible with the motor running and only a light clicking when it flicks on with ignition (on an LPG tachometric relay, so get 3 seconds open then off til tach signal) the good bit is it cycles up and down as needed so its not running flat knacker all the time heating up your fuel.

I had it easy fitting it under a ute, may be different with a wagon.

I really noticed the difference on really steep climbs with the lift pump in, used to stall and be gutless, lost a lot of that with the lift pump. May have been a tired pump, but it did fix the dramas, also lost a flat spot I had.

[doolie]

fuel line .sucking air at connections.air is easier to suck in than diesel,therefore it continues to suck air and will not start.hand primer has more grunt than injector lift pump therefore draws fuel through.also flex fuel pipe may be porous letting in air.