# Fuel Problem on a 2L Diesel engine in a 1984 Toyota truck.



## ai13 (Sep 1, 2010)

This is my first post here and I apologize if I have missed a solution to this elsewhere, but the search function did not turn up anything useful and neither did my browsing. 

I have a 1984 2L Diesel Toyota truck (everywhere else in the world it is probably called the Hilux) and I recently broke the throttle cable. This is not normally a problem, and I was able to replace the cable a month later when the new one arrived. The problem I am running into now is a problem with the fuel system.

When I attempt to crank the truck, fuel does not seem to be flowing (injected if that is the proper term for it) into the engine block. I have tried removing a fuel line and turning over the engine, however no fuel came out when I did. My fuel gauge reads 1/4 of the way full, so I am stumped by what could be causing the problem. My best guess is that in the time that it was sitting, impurities in the fuel settled, coagulated, or otherwise blocked a major fuel line and need to removed before the fuel will start flowing again.

I attempted to start the engine with starter fluid/spray and was successful until the starter fluid had been consumed. 

Thoughts, tips, help? Anything would be greatly appreciated.


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## kjms1 (Jun 4, 2010)

first tip 
NEVER use starter fluid on a diesel use WD-40

did you remove the fuel line going into the injector pump or coming out of it ... if you checked fuel before it goes into the pump then check the fuel pump and fuel filter
if you check it after it comes out of the injector pump check it before the injector pump


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## ai13 (Sep 1, 2010)

I checked the fuel lines as they entered the engine block, so that would be the fuel line coming out of the fuel pump. I will check the fuel lines leading into the pump, thanks for the advice. 

As for the starter fluid, it did say it was made to work on diesels. Perhaps I messed up, perhaps you think I used gasoline engine starter fluid, either way, thank you for the response.


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## ai13 (Sep 1, 2010)

I checked the fuel line leading into the fuel pump throttle assembly, and there was no fuel flow even when I attempted to turn the engine over. I only tried for 3 seconds but as nothing came out in that time, I stopped. I am now following the lines back to the fuel tank to look for a blockage.


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## ai13 (Sep 1, 2010)

I disconnected the lines leading out of the fuel tank and attempted to crank the engine and nothing came out of them. I then put 5 gallons of diesel into the tank, bringing the fuel gauge from 1/4 to 1/2 full, primed the engine with about 60 presses of the priming shaft, and attempted to start the engine again. Still no fuel flow. I believe that this means that there is a problem with the pump in the fuel tank. Is that assumption correct?


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## Wrench97 (May 10, 2008)

Is this a SD25 engine?

Does it have a pump in the tank? Most of the time if it has a primer pump that means a mechanical pump mounted on the motor.


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## ai13 (Sep 1, 2010)

No, it is a 2.4 liter 2L diesel engine and it evidently has a primer on the fuel filter, and a pump in the fuel tank.


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## kjms1 (Jun 4, 2010)

If its got the pump in the tank lets do this first find the fuse box and find the fuel pump fuse and check that


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## ai13 (Sep 1, 2010)

All the fuses look intact. What is next?


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## Wrench97 (May 10, 2008)

It should have a fuel pump relay also, check that current flows through the relay when the key is first turned on.


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## kjms1 (Jun 4, 2010)

like wrench said find the fuel pump relay turn the key on and you feel the relay click on or hear it click on .... might take 2 ppl to do this


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## ai13 (Sep 1, 2010)

I cannot find a relay labeled "Fuel Pump Relay", however I did find a relay next to the glow plug relay that had no current flowing through it when the key was turned on. I would have tried tracing the wiring back from the fuel pump, however I cannot find it either. As I said before, I evidently have a fuel pump, the Chilton manual for my truck says that I should have one.


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## Wrench97 (May 10, 2008)

How many wires go into the fuel tank?


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## ai13 (Sep 1, 2010)

I can only see 2 wires leading to the fuel tank, I guess that means that there is not an in tank pump?

I would like to appologise for the delayed response, for some reason the update seems to have been sent to my spam box.


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## Wrench97 (May 10, 2008)

Doesn't sound like it, most of the Nissan Diesels from the 70's & 80's I've seen had a mechanical pump, put the fuel lines back on the tank and loosen the line going to from the primer pump to the injection pump on the injection pump side, pump the primer pump you should fuel out of it.


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## ai13 (Sep 1, 2010)

I pressed the priming piston about 180 - 200 times. Aside from an initial squirt, nothing else came out. I did check that there was a little gust of air out of the tube during each pump and there was. What next?


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## Wrench97 (May 10, 2008)

Lets make sure I have the correct fuel system layout, the line from the tank goes to the primer pump or to somewhere else first?


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## ai13 (Sep 1, 2010)

Alright, the best way to do this is probably to provide pictures. 

These are the three lines leading out of the fuel tank.
http://img32.imageshack.us/img32/1825/img0477m.jpg
This is the line that leads into the chassis and ends up somewhere I cannot find.
http://yfrog.com/bcimg0478j
These two enter the engine compartment. 
http://yfrog.com/5himg0468ysj
This one enters the injector pump assembly immediately here.
http://yfrog.com/61img0474ej
Another view.
http://yfrog.com/bhimg0470etj
This is the sediment type primer pump (I think I have that right, then again it might just be a filter, either way that knob on top seems to act like a priming lever)
http://yfrog.com/j0img0475hij
And here is where it enters the injector pump assembly.
http://yfrog.com/83img0476kj
And this is a shot of the whole pump side of the engine.
http://yfrog.com/j0img0472qj
I apologize, I forgot to rotate that last one.

To answer your question, according to the schematics I have for the engine, I think the fuel line enters the injection pump after the filter/primer and then gets directed into the engine.

Did this help?


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## Wrench97 (May 10, 2008)

Loosen the banjo nut on the injection pump line after the primer if you do not get fuel out of it, it's probably going to have a suction line leak between the primer pump and tank.

One way we check for suction leaks is to run a line from a fuel can to the primer pump, pump it up and see if you get fuel if you do see if it runs off the can.


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## octaneman (May 13, 2009)

Hi ai13 

The only way to be certain you have a electrical fuel pump is to use a broom handle and listen for the pump, at worst drop the tank and open the top. If there is a mechanical fuel pump it should be in close proximity to the primer which I don't see it from the pictures you provided. On your ninth post you said you pumped the primer 100+ times and felt air through it but no fuel, so your problem lies before primer not after it. If any sediment or water has built up it would be noticeable from the fuel filter which from the pictures shown has never been touched. Does the water in fuel light remain on ? Find out what the relay next to the glow plug relay does, if it is a fuel pump relay you will need to be sure. 


post back your findings.


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## ai13 (Sep 1, 2010)

Will do, however it is taking a while. I will respond when I know more.


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## ai13 (Sep 1, 2010)

wrench97 said:


> Loosen the banjo nut on the injection pump line after the primer if you do not get fuel out of it, it's probably going to have a suction line leak between the primer pump and tank.
> 
> One way we check for suction leaks is to run a line from a fuel can to the primer pump, pump it up and see if you get fuel if you do see if it runs off the can.


I tried that, nothing came out, and no fuel was brought in to the pump. I think that may be the problem. What is next?


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## octaneman (May 13, 2009)

On some trucks there is a trap door inside the trunk underneath the carpet to access the the fuel pump. If your truck has one it may not be necessary to drop the tank, I've looked at schematics on 84 diesel trucks although they are 2.4 L , there is an electric pump on it. The 2 wires that you see are for the pump. 


post back your findings.


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## ai13 (Sep 1, 2010)

That sounds like my truck. I have a 2.4 liter 2L engine, I do not know why it is called 2L, but it is. I looked for a trap door, but could not find one, I did find a lot of dirt however, I should have cleaned that a while ago , I also checked under the truck, and there was nothing resembling a fuel pump there.


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## Wrench97 (May 10, 2008)

From what I can find it looks like it is a electric pump, see if you can locate the relay, it should look like this> http://info.rockauto.com/getimage/g...SMP/RY276_FULL.jpg&imagekey=39237-0&width=450


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## octaneman (May 13, 2009)

From the first picture you posted, the gas tank's position is slightly tilted more forward to the front of truck than to the rear where the trunk is. Look for the trap door under the rear passenger seats. If it's not there drop the tank.


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## ai13 (Sep 1, 2010)

I do not have rear seats, looks like I will have to drop the tank. What should I look for in near the tank.


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## octaneman (May 13, 2009)

When the tank is on the ground you will have to remove the pump assembly. The top assembly either has a locking ring on the tank or it's bolted on with screws. If there is a locking ring there are 2 tabs that are in the locking position , by using a hammer an chisel turn the locking ring counterclockwise until its off. Then grab hold of the assembly and lift it up, the pump will be inside with 2 wires connected on it's terminals along with a rubber grommet and filter screen. There is an O-ring that is seated on the tank be extra careful not to damage or loose it, you will need it to put everything back together. Without the O-ring the gas tank will leak when it's full.


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## ai13 (Sep 1, 2010)

I seem to have found the solution:

I was testing the primer pump again, my first test had shown that it had not been able to function as a pump, so I tried siphoning fuel out of the fuel tank through the hoses connecting to the primer pump. I was successful with this. I had tried draining the "water" out of the pump eariler according to the instructions in the truck manual, however I believed that the filter was still clogged, so I completely removed the drain plug and emptied the "water". I then refilled the pump and filter with new diesel and reattached everything. I then primed the pump around 200 times. 

After all of this the truck started. A clogged filter, thats all. :sigh:

Thank you for all of the help, I would not have gotten this far without this forum.


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## antagonising (Nov 26, 2010)

Thanks for this thread. I just wanted to clear up a couple things in case anyone else comes to this for help.

It is a Toyota and not a Nissan. Nissan was mentioned a few times in this thread. It is a truck and not a car. No trunk or back seats.

I just bought a 1984 Diesel 4X4 Toyota that I was told had a blown fuel pump. After many phone calls and frustration I discovered this: It does NOT have an electric fuel pump! For some reason the Chilton guides show the gasoline fuel pump and not the diesel. My local auto parts store even shows an electric pump. I contacted the dealer, he looked up the VIN# and confirmed it only has a mechanical fuel/injector pump.

So after looking for fuel pump relays and fuses and laying on my back in the mud, I discovered they didn't exist in the first place.

Now as soon as I get the fuel filter cleaned and primed, I'll find out if I saved the $300 for an electric pump that I dont' need.

Thanks again for the thread!


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