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This dives right into replacing a mechanical fuel injection system on a 1981 VW diesel Rabbit with a 1.6L engine. Bosch VE pump. Includes: Installi...
You will need a working pump, I recommend buying a rebuilt pump. Rebuilding these pumps is hard. Even if you get it back together, there are several...
Diesel engines have fuel injectors instead of spark plugs. It is a precision part so buy new ones if you can - but they run $50 to $150 each.
Also get new heat shields. They say to replace these every time the injectors are removed.
The fuel injection pump is complicated and has to be carefully calibrated. Re-manfuctured they are about $500 -- got mine from Parts Place VW
These parts are important, but do not come with the pump. I pulled them off the old one.
Install the fuel injectors. Make sure the old heat shields are out. Put in the new heat shields. Put a little high temp anti seize lube on the thre...
The pump mounts with 4 bolts. 3 on the face and one at the other end. One bolt is on a bracket and has to be tightened through a hole in the sprocke...
Now is a good time to put this hose in place.
Line up the timing marks on the sprocket and pump. Then lock the position using this special pin. It goes through a whole in the sprocket and into a...
Paint the cylinder head cover with engine paint. Clean and sand it first.
Top dead center -- or TDC -- is sort of the starting point for the engine. When setting the timing everything gets lined up at TDC. Line up the timi...
With the cover off the cylinder head - rotate the camshaft to TDC. Both lobes over the first valve are pointed up and a flat timing tool fits in a sl...
Setting the timing may take a few tries, this is what it looks like when you are close, but are not given a cigar. The pump is lined up but the flyw...
It is hard to keep everything lined up. I had to loosen the sprocket on the camshaft. To do that, you have to lock the camshaft in place (withouth ...
Set the knob so it is pulled out just a little. Push the cold start lever all the way to the passenger side. Attach the cable.
When starting the engine you pull out this knob.
The accelerator cable should be totally replaced, for now I put the old one back on. The cable hooks on a bracket that is transferred from the old pu...
Install a fuel line from the filter to the pump, use a clear one.
Install a new gasket for the cover. It has 3 parts.
Put the cove back on. I sprayed the edges that will touch the gasket with graphite, there was some bare metal and I didn't want to paint it.
The timing has to be fine tuned using a dial gauge. If you have experience you might be able to do this 'by ear' with the motor running. The gau...
Had to remove this thing to fit the dial gauge in place. It goes into the side of the pump.
There is a bolt in the side of the timing pump. It is in the center on the drivers side. This is where the gauge will go. Take out the bolt, do not...
Screw the dial gauge into the hole where the bolt came out of.
when you do the fine tuning with the dial gauge, the cold start knob has to be pushed in
With the dial gauge in place rotate the engine backwards a little bit. You are looking for a point where the needle stops moving. Then set the dial g...
Set to TDC and read the dial gauge. This is the value we are trying to get correct. Look up the calibration value in a book. Then - loosen the bolt...
With everything perfect, tighten up the bolts holding the pump in place. The pictures here show me setting the wrong torque and breaking a bolt. So....
If that worked out, remove the dial gauge and replace the bolt with the washer. Also, put back the thing we had to take off.
The fuel lines that go from the pump to the injectors are metal and curvy. I bought new ones, but they can probably be cleaned.
Each fuel line is different. Fit everything in place loosely. Don't break anything. Don't cross thread anything. Use a light touch. Get everythin...
Now tighten all the joints. Tighten just enough -- you don't want to break these. It will be easy to tighten them latter if there is a leak.
There are barbed ports on the injectors. This is for fuel return as not all the fuel gets injected. Replace these with new hoses. The injector al...
There is a solenoid on the pump that controls the flow of fuel. If you have to fix the wire, here is how.
Not all the fuel gets injected so it has to go back to the tank. There is also a low pressure resevoir in the pump which always has fuel going in and...
Everything is now installed... probably. To test things out we will need some power. It is hard to start the first time. I hooked up a giant power ...
The pump and all the fuel lines need to be filled up with fuel. This already has an extra electric pump. I ran that for a while to get the air out a...
To start the engine; pull out the cold start knob. Turn the key part way to turn on the glow plugs. Put the car in neutral and set the hand brake. H...
Here are some videos where nothing works and nothing happens. More of the same.
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I found mine fallen off beneath the pump - hoping that there's some way to attach it without removing the whole injection pump.
Here are the details that I can recall:
The top bolt passes through the top hole in the metal arm, then through the pump mounting holes, then into a threaded hole in the left bracket.
The bottom bolt is attached to the metal arm, it passes through the pump mounting holes then through a non-threaded hole in the left bracket, and it is fastened with a nut. This nut is hard to get to, you have to line up a hole in the sprocket with the bolt, then pass the nut through the sprocket and tighten to the bolt.
In step 28, you can see that I screw this up and break the bolt.
Indeed, I just found the third securing bolt fallen off, and the injection pump is loose, which would explain why the engine is running so rough, even though the drive-belt is tensioned properly.
Since I don't have a dial gauge, and the drive belt has not been removed, I think I can just line up the line on the pump with the line on the bracket and tighten the bolts down?
You can can also start with the pump rotated to far in one direction (so it injects late, I think this is with the pump to far towards the engine), then rotate the pump to advance the timing until is sounds correct (away from the engine, I think).
I might do the same thing this weekend, you've reminded me that I have to replace that same lower bolt. I thought my engine mounts were bad (which I am sure they are) but maybe the timing is just off.
To advance the injection timing, you rotate it (the top of the pump) towards the engine. I just did it (with a dial gauge) about an hour ago. A little movement does quite a bit of adjustment, so don't go to the stops! There will be too much advance if you do (assuming all is at TDC).