Long Range Petrol tank access issue

[mudnut]

Not needle and seat but second stage as it acts differently on gas. The fact that it gets better as it warms up points to that. I had the same problem. i learned how to quickly get the second stage to activate. When it was cold and couldn't get high revs, I pulled over, popped the bonnet and activated the butterfly. The carby would then perform properly while still cold.

But if it flooded, you may have some crud stuck in the needle and seat.

[Bigcol]

Fuel pump/related electrics definitely have a problem. As you might have seen from the pictures, LRA has done a poor job with electrical wiring for the pump & sender near the tank. Probably one of causes of the problem, if not the whole reason.
I am putting the pump through proper diagnostics regardless of that to make sure it's not on it's way.

Carby's been through a kit not that long ago.
Float chamber fuel level is usually good. Originally it was always quarter full, but last year I adjusted it to be half full all the time.
It went ok since then.
Having said that, since I started having fuel pump issues, I started giving the fuel pump power directly from battery, bypassing the
Fuel Pump Control Unit(Fuel Pump Relay).
That caused the carby to flood few times so far.(as soon as I connect the direct power line to the fuel pump).
So, it sounds like carby also developed a problem.
I don't think it's likely the fuel pump to put out excess pressure.
Fuel pump start getting weaker when they are on their way out don't they? They don't develop extra grunt before they die, do they?

I have only ever had 2 electric fuel pumps die on me

both times they just stopped working


your wiring on your fuel pump does not need to be insulated, it is sufficient as it is with the plug & insulated wires

you would need air (or a gap in between the connectors) to make the electrical connections spark and then go B A N G

[mudnut]

Another thought. when you connected the fuel pump to power and it flooded, I wonder if the pressure needed to be reduced by the fuel return solenoid?

[dom14]

Another thought. when you connected the fuel pump to power and it flooded, I wonder if the pressure needed to be reduced by the fuel return solenoid?

Yes, the thought has crossed my mind. But, I followed your RB30 thread to get an idea about the way the fuel return solenoid works.
I guess it kinda possible 'cos fuel return solenoid may come to action bit too late to stop the flooding.

BTW, flooding only occurs if i do the following actions in below order(afaik).
1) I leave the ignition on first
2)I connect the make shift wire to the FPCU wire that goes to the fuel pump(green with red trace).
3) I connect the other end of the make shift wire to the battery positive.

The order of the 2 & 3 won't matter obviously.

If I do the 2 & 3 first and then turn the ignition on, flooding of the carby apparently won't happen. (I can see the petrol still completely
fill the float chamber, but I was still able to start the engine. If I do 1 first and not quick enough to start the engine, the flooding happens way too much and I can't start the engine until I clear the flooded float chamber.

I must admit, I haven't properly checked the function of the fuel return solenoid.(it slipped my mind).
I think it's about time I do that as well.

The thing is whether I high rev or low rev under the bonnet, the float level stays in the middle when I cold start the engine. It only start stalling(and unable to generate enough power) when I start driving.

None of the above problems exist with LPG.

That's why I thought to start with the tank end and rule out all the problems.

I most certainly need to check the fuel return solenoid & carby properly.

[Yendor]

I've had a look in the workshop manuals I have and this is all I can find regarding carby model fuel pump specs.

Carby model specs.jpg

[dom14]

I've had a look in the workshop manuals I have and this is all I can find regarding carby model fuel pump specs.

Carby model specs.jpg

Thanx mate. I've been busy running around, I didn't get a chance to carefully look in the manuals.
20KPa translates into approximately 3psi.
As an el cheapo external solution, below is all I need atm.
They are rated 3-6psi.

http://www.ebay.com.au/itm/252333921...84.m1436.l2649

If the pressure is enough, they are not bad as a backup.

I prefer to use a strainer for the tank pickup.

Will you be able to suggest something?

[dom14]

I have only ever had 2 electric fuel pumps die on me

both times they just stopped working


your wiring on your fuel pump does not need to be insulated, it is sufficient as it is with the plug & insulated wires

you would need air (or a gap in between the connectors) to make the electrical connections spark and then go B A N G

Yes, I realized that, though when you fill the tank at the servo, bit of air can get into the tank via the fill and breather lines. I reckon most possible time a spark from the intank electrical connection can ignite would be the time you fill the tank at the servo. Once we shut the fuel cap, the limited air inside the tank probably limit how for the ignited fire can go.

I still think petrol submerged electrical components are bad ideas. It's bad for two reasons.
Petrol does NOT conduct electricity afaik. So, petrol getting in between the electrical connectors inside the tank can weaken the electrical conductivity of the metal connections(I think). Or the gunk in petrol(the die) can build up inside the electrical plug. The other reason of course is the electrical spark hazard. I'm sure Nissan engineers thought "long and hard" about the second reason. Otherwise we would've heard of petrol tank explosions from intank fuel pumps like RB30 Patrol fuel pump.
It couldn't have been rocket science for Nissan to extend the wire out and make the electrical connection external. Same could've done with the sender as they did with the oil pressure sender. For a fuel pump they ask $800, I think it's well worth to make them far safer and last longer.

I'm leaning more towards drilling a hole on the old intank pump plate and creat a new pickup line for an external pump. Far less headaches that way I reckon.

I'm only wondering right now whether I should use an intank strainer/filer or not.
Using a one would prevent the pump from failing from petrol gunk buildup over time, but also create the added headache of strainer itself getting blocked over time(since it's intank one, it won't be fun to lower the tank again).
NOT using an intank strainer/filter would kill the pump early, but I would still have the choice of just replacing the pump without having getting into the tank one day to replace the strainer.

Any suggestions for an intank strainer mate?

Thanx

[dom14]

I guess I should be able to adapt one of these fuel pump strainers for my tank.

http://www.ebay.com.au/itm/121024602...84.m1436.l2649

http://www.ebay.com.au/itm/172058597...84.m1436.l2649

http://www.ebay.com.au/itm/121024662...84.m1436.l2649

[dom14]

I found this intank pump that claims to suit RB30S(Patrol).

I'm not sure about how it would fit though. Picture they provided is not so helpful or convincing.
Doesn't look anything like the pump I pulled out of the RB30 Patrol.

http://www.ebay.com.au/itm/130982930...84.m1436.l2649

[Bigcol]

what about something like this for the fuel strainer.........

http://www.ebay.com.au/itm/Brushcutt...-/221683320790

not sure about the other one though, RB's are not my thing............