Fuel Delivery Help [1994 2.7TD]

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Joined
May 1, 2023
Messages
15
Hello,

I'm new here, and new to Mavs.

I have an old barn find (1994 Ford Mav, 2.7d), and have changed all fluids and filters bar coolant (will do that soon), changed the battery and she cranked up fine. I haven't changed the little fuel filter which is really hard to get at near the high pressure fuel pump.

Before starting her, I drained the diesel tank and put in 10 litres of new fuel. Fuel that came out was spotless - no bug and no gunk came out of the tank.

However, after running her for a few minutes, she started to struggle and show signs of lack of fuel.

I was able to prime the pump (over the fuel filter) by hand, and this got her going again, and she started to starve again after a couple of minutes.

Looking at the intake / outputs from the fuel filter, when I press the hand pump there is a strong puff of air from the filter housing to the line leading to the engine, but there is no vacuum at all in the intake. I'm assuming there should be.

Pulling these lines did not result in much fuel dripping at all, whereas when I change the fuel filter in my Vitara, there is a lot of fuel sloshing about.

Given how it was running fine at the start, I'm hoping that there is no problem with the high pressure fuel pump, and instead this is something to do with the the fuel lift pump, the fuel filter, or a vacuum leak in the fuel filter. However, I can't see any diesel leaks. Something seems to be preventing the fuel from getting into the block.

Can anyone recommend anything?
 
Hi and welcome, I assume you have changed the fuel filter, the small filter you talk of near the pump I assume you mean the "mini filter located in the banjo bolt" if so it is well worth looking at that as if it is blocked or restricted causes pump primary over pressure and it will not run well in this case, but you could also be talking about an extra filter that has been installed? the lift pump on these is incorporated in the front of the injector pump, so the whole system IP back to the tank is under negative pressure, so any pin holes in the line and it will suck air, as a temporary test you can stick a can of fuel on the roof and gravity feed it, if it runs OK then you have eliminated the IP and need to check the fuel lines, this is just a preliminary run through of possible causes, Rick
 
Welcome aboard.

Some cheaper fuel filters have been known not to seal and let air in. As Solarman says the metal fuel lines tend to rust and leak especially over the rear axle area so that can be a source of air too.

Incidentally if you changed rear diff oil then it does need to be LSD Oil not just gear oil.

Once you get the old girl running it should be a reliable vehicle, the 2.7 diesels seem to be almost bullet proof. The early ones that are totally mechanical fuel pump and no ecu’s can be a little sedate when you drive them.
 
Thank you both. Will check this.

Haven't gone near the rear diff oil yet. I want her turning over properly before I start messing with movement, and all the hassle that will entail!
 
Got it going. Bought an inline hand pump, and used that to bring the diesel up from the tank. Saw there was something off with the filter housing, as the diesel wasn't passing through the filter, but was leaving via the water drain. Stripping the housing and the water drain, cleaning them and reassembly seemed to fix the issue, as fuel started to leave the filter the correct way.

Lovely sound when she started going!

https://youtu.be/F2JYKcGUrD8

However, the clutch is slack. I topped up the fluid, pumped the clutch for a while and then bled the master cylinder. No air coming up, just fluid.

Crawled in underneath her, and the slave cylinder seems to be dry.
I used a syringe to try and flush the line (when removed from the slave cylinder), and fluid seemed to make it through. However, there wasn't a buildup for fluid in the slave cylinder after I reconnected the line.

Any advice / help?

The only other issue is that the 'water in the fuel filter' light is on all the time. I guess there is some sensor or wiring issue.
 
Your engine sounds to be running sweet, looks like yours is the earlier truck without the intercooler and electronics.

Clutch can be any number of things. I’ve listed below what I had to change on one of my Terranos that had clutch problems.

Check the flexi hose that connects to the slave cylinder, these perish and the walls of the hose tend to swell instead of let the fluid through to the cylinder.

Also on the flexi joint you will notice a metal pipe that goes off and ends above the rear axle with a bleed nipple on the end. This is called a Damper Pipe. This often leaks above the axle. I removed the pipe and had a blanking plug instead but people have come up with lots of methods of blocking the metal pipe.

Finally I have not had this problem but the Master Cylinder could be faulty, I don’t know of a way to diagnose this part.

Hopefully I have been able to give you some pointers.
 
Thanks Jim.

Are those flexi hoses hard to source?
I can remove it from the slave, but the nut which is locking it to the rigid pipe (feed from master) is seized and starting to ring when I get a wrench on it.
Time, I think, to break out the vice grips but I don't want to do that until I have the replacement handy.

I think I'll also have have to replace a bunch of flexi hoses associated with the brakes, so a good source would be appreciated!
 
Last time that I needed one I got it from local motor factors but probably better checking before hand.
I do remember people fitting one of the front brake flexi hoses instead as that fitted and completely did away with the damper pipe.
If you are worried about the rigid pipe being corroded together it might be easier to have that pipe made up from a local factor perhaps and replace the whole lot.
It’s a pity you are not closer to Huddersfield as I think I might have the brake hose in my garage.
When I sell my Maverick I will probably let all my spare parts go at the same time.
 
I'm guessing this has to be a reasonably standard part, one that was on plenty of nissans, so should be gettable.

I think (hope!) the rigid pipes are fine, and either way it is probably worth replacing the hose anyway.

Thanks for the steer, will check with the local guys.
 

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