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Replace a mechanical fuel injection system on 1981 VW Rabbit diesel - Bosch VE

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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:
Installing pump, injectors, and fuel lines.
Setting timing.

You should still use a service manual, this one is very good but hard to find: 
Volkswagen Rabbit/Scirocco/Jetta Service Manual, 1980-1984: Including Pickup Truck, Convertible, and GTI (Robert Bentley Complete Service Manuals)

This one is less good, but you can get it easy from amazon:
VW Rabbit Diesel 1977 thru 1984 (Haynes Manuals)

Everything is in chronological order -- it starts with the fuel system already out.

A word about the motivation for this instruct able:

Motivation:

"assembly is the reverse of removal"

There are very good reference books for working on cars; Haynes, Chilton,
Bently. However they have a few drawbacks; the first is that
most of the photos are black and white and grainy.  It is not their
fault, it is hard to take pictures inside the engine compartment or
under the transaxle.  The second major drawback is the statement
"assembly is the reverse of removal".  Most manuals are based an a
complete teardown of the vehicle.  This is very useful if you want to
take a car apart peice by peice.  However, once you take the car apart
and have peices all over the garage, spilling out into the drive way
and family room.  You are generaly left with these instructions
"assembly is the reverse of removal."  Even if you follow the
instructions backwards, line-by-line it is very difficult to get
everything back together.  In my opinon these books should start with
a pile of parts and end with a completed vehicle.

So I have started this instructable with parts all over the place and
every bit of timing out of sync.  Hopefully, when you hit the words
"assembly is the reverse of removal", you will find this instructable
and it will help yout out.



Why repair a car from 1981?

55 miles per gallon, no modern emissions rules, cheap parts, and cheap
insurance.

Why diesel?  Well, check out the work being done by Rudy Behrens of
BEAR Oceanics.

He is building living robotic systems that grow oil rich algea and
process it directly into usable diesel fuel.

Here is a nice article on the project: here

What else do you need to know?

Where to get parts:

http://www.partsplaceinc.com/   -- These are VW specialist, every part has been perfect.  Very good if you want to buy 'kits', such as all new hoses or a complete engine rebuild kit.  They also carry many specialty tools and such.  They are a 'real' store, so you can get them on the phone an they will be able to help, keep in mind that they are also minding the shop, so they might be busy with physical people.

http://www.partsgeek.com/  -- Often have the best prices (not always though) good for pretty much anything for any car, but the descriptions are very brief so you need to be careful when ordering.  Fast shipping.

AutoZone is okay, but prices are sometimes high and some parts ship slow, if one part is back-ordered or custom they delay the whole order.  Of course there is probably one near by, so you can go there in person, cheap fluids - expensive tools. I like smaller stores better. 

Local salvage yard  -- In New England you will be about salvage cars tend to be around 10 years old.

Ebay -- I have not had good luck.

Amazon -- Look for deeply discounted professional tools.  I used this and it worked: 
VW/Audi Bosch Diesel Fuel Injection Pump Timing Indicator Tool
Harbor Freight -- most of my car tools are from here, go to the store if you can.  I like the color coded wrenches/sockets.

Home Depot  -- not too useful.

Craigslist -- Look for someone who is getting rid of a garage full of VW parts, or a parts car.

Also  -- The car I am working on is the former ' Clean Machine ' from Gordon Collage in Mass.

Also - I like this wrench set from Harbor Freight because I can remember the colors....  link
 
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Tarps2 years ago
That metal arm that you bolt to the left bracket - what does it do? Does it have nuts on the end of the two bolts?
I found mine fallen off beneath the pump - hoping that there's some way to attach it without removing the whole injection pump.
marc.cryan (author)  Tarps2 years ago
The photo is misleading -- the metal arm goes on the outside of the injection pump mounting holes, So the injection mounting holes are between the metal arm and the passenger side (left) bracket. As far as I can tell, the only purpose of this weird piece is to hold the bottom mounting bolt in place while you put a nut on it. It is falls off, but the injection pump is still on tight (can't be moved by hand, no matter how hard you try), then it should be fine.

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.

Thanks - that's super helpful!

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?
marc.cryan (author)  Tarps2 years ago
Yeah -- line everything up, then you can fine tune it by ear. With the engine running and the bolts pretty tight, you can slightly rotate the pump by hand until it seems like it is idling well. Then tighten everything up.

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.

This is critical for good mileage

Just my 2¢ on advancing the pump...

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).

rdefranco11 months ago
I was so lost trying to reconnect wiring , until I found your photos .
Thank you much .
Brooksi1 year ago
Thank you, - The info about using the Cold Start on Diesel Rabbit is very useful for me. (for a fiction writing project of all things) .

I have a Diesel Toyota (Landcruiser with 2h engine) . It uses the older inline 'jerk pump' injection system and pre-combustion chambers, and will run on about anything oily, including kero blends.
The Glow plugs act as a Hot Spot in 2h engines, to help ignite the beginning of each spray of diesel - quickly. Sprays of diesel must burn as it enters engine so there is never much unburnt fuel. Lag in ignition of the spray will result in KNOCK as the unburnt spray ignites - BANG - which breaks pistons.

My 12v glow controller cost more than the truck , so I replaced with it with a piece of wire and a verbal countdown (of magical mechanic words), when key is in glow position. It starts and runs fine so long as I remember to use full throttle, - required in old bosch vacuum governed pumps. - and yes it does have a throttle plate for to make a small vaccum for the governor. That vacuum represents a pumping loss when the engine is running.

thank you for your instrucables on injection system changeout , and the aquaponics .
marc.cryan (author)  Brooksi1 year ago
Glad you like it! --- thanks for the note.
Marc, this is a great instructable! Thanks for contributing. I own a modern common rail injection diesel car, but seeing how the old ones work is great. Thanks for this tremendous piece of work!

Koray
marc.cryan (author)  thearchitect2 years ago
Hi Koray -- Thanks so much for your kind comments -- I figure, if I don't finish the car, at least I'll have posted some instructables! - Marc