The Lockdown jobs ,sd22 fuel filter

[jreddy]

Hi Guys I have a few jobs that need doing with my Double cab 720 sd22 .My first job is to set up the fuel system as it came out of the factory or at least to figure out why last owners  removed the first (primary filter ) out of the system .I have two pipes coming up at the bulkhead where the brake/clutch master cyl is(Both of these pipes not connected to anything) .Is this where the primary filter should be?? is there a bracket ?? the strange part is that one of the pipes is teed off further down and goes to the injection pump  and the other side heads back to the 4wd transfer case .(am i going mad)the other pipe runs from the tank straight to the bulkhead .ill wont explain any more maybe someone who knows or that has a diagram or pic of the set up might help thanks in advance .regards john .

[Charlie69]

Wayno knows the diesels.

[wayno]

I would really need to know more to be able to understand what you have and are talking about, it would help a lot to have photos.

That said there are 2 metal fuel lines on US models, one is for supplying fuel from the tank, the other is to return fuel to the tank.

From 1982 on the fuel supply line coming from the tank went to a diesel fuel pre-filter on the firewall, then the line went from the pre-filter to the bottom of the lift pump on the side of the injection pump(it has the primer pump connected to it), from the lift pump it goes to the spin on fuel filter "IN" banjo fitting pointed sideways, you can see it pointing towards the engine in the photo below.

Next the fuel comes out the fuel filter thru the "OUT" banjo fitting in the middle and that feed line goes to the injection pump.

The back banjo fitting has 2 barbs/hoses,  a line comes from the injectors and is a return line from them, it goes to the small barb, the other barb goes to the return line going back to the tank.

 

This is the best I can do, I believe you have an inline injection pump like we have in the US.

Do you have the spin on fuel filter assembly or is it gone?

 

[jreddy]

Hi Wayno thanks for quick reply, I know what I'm saying makes no sense ,I'll have another look and take a few pics ,I had expected that they would both be coming from tank .I'll take a few pics and get back to you thanks regards john

[wayno]

There are actually 3 lines coming from the tank that go to the engine compartment, there is the fuel feed/supply line, there is the return line, and there is the vent line, the vent line on my diesel powered trucks just vented on the driver side near the radiator over flow tank here in the US(left side), but on gas trucks that line went to a canister with a lot of other vacuum lines, it is also routed with the rest of the lines on the right side but it crosses the engine compartment to the left side on the firewall.

There are 2 metal lines that come up next to the oil filter, the large one is the fuel feed line, the smaller one is the return line, but it sounds like yours have been deleted, there is likely a reason, I have no idea why this would have been done unless they were plugged, do you have another metal line or rubber hose feeding your lift pump, can you blow air thru the existing lines to see if they are clear, can you plug one end, put air to the other end and see if there is a leak in either of the lines?

Again the big line is the fuel supply/feed line, the other is the return line, and the one that crosses the firewall is the vent line.

[jreddy]

Hi Wayno you are 100% correct I had found the big rubber hose(Main feed) but it was the only one that didn't have a steel pipe on the end like  the other 2 have. The other are flared at the end which I assumed incorrectly was supply and return, thanks for your help .why would that vent pipe be coming up to the fuel filter? You will have to excuse my questions I'm not a mechanic just a self taught numpty. Thanks again

[wayno]

I don't know what you mean or are talking about when you said,  

 

"why would that vent pipe be coming up to the fuel filter?"

 

Here is a photo of the two lines coming up near the oil filter, the larger front line goes to my fancy pre-filter(not stock).

 

In this photo you can see the return line coming from the fuel filter going down to the return metal line, you can also barely see the fuel feed line going from the pre-filter on the firewall to the lift pump on the lower part of the injection pump, you can see the line going from injection pump to the fuel filter assembly feeding the fuel filter, you can see that line comes from the top of the lift pump, and the injection pump line next to it, that line feeds the injection pump from the middle banjo fitting on the fuel filter, you can see the back banjo fitting with 2 lines, the big line goes to the fuel return line back to the tank, the smaller hose is a return line from the injectors themselves.