Another Saturn TDI Conversion

specialed1995

Well-known member
Joined
Feb 1, 2015
Location
United States
TDI
1Z 1.9 TDI from 1996 B4 Passat
Since the weather is turning colder I've had some spare time to start working on this project again.

I extracted the broken bolt that snapped off many months ago after soaking it in penetrating oil several times and working it in with the air chisel. It finally broke loose and came out turning it with a pair of pliers.

I also removed the factory belt tensioner and sawed off the boss that it goes through on the front to make room for the new tensioner mount I need to fabricate. As I said before I’m using jimbote’s setup which retains the A/C compressor but deletes the power steering pump. I’ll have to do some calculations and figure up exact how everything needs to be.

I removed the side motor mount as well (the one right in front of the turbo), as I’ll be fabricating mounts similar to CFM’s designs and won’t be needing it. Will probably end up selling any leftover VW parts I end up removing on this conversion.


The intake manifold was very gunged up after 335k miles so I removed it to get it ready to clean. I plan on soaking it in diesel fuel and scrubbing it with a brush etc. to loosen and remove the carbon. There’s also a bit built up inside the cylinder head, so I’ll rotate the engine around until the intake valve for the cylinder I’m cleaning is closed, and clean and scrub the port with a brush and blow it out with compressed air, plugging the other open ports of course. If anybody has any tips or suggestions about doing this please let me know.


I’m going through the wiring harness now and labeling all the connectors to see what I need to keep and what can be gotten rid of, and I’ve run into some trouble. The 24 pin connector that goes to the engine wiring harness won’t come unplugged, and I need to get it unplugged to replace the glow plug wiring harness, as it has dry rotted and fallen apart.


What’s the trick to undoing this connector? I slid the plastic ring that goes over the rubber seal back, but try as I might it wouldn’t come apart. I could see no locking tabs anywhere so I suck a flathead screwdriver around the base and lightly pried on it thinking it was stuck. I didn’t want to pry too hard and break it so I stopped and decided to ask for some help. If anybody could offer a tip on how to unplug it I’d be grateful!


More work on this project is coming after the holidays!
 

ToddA1

Top Post Dawg
Joined
Aug 3, 2011
Location
NJ 08002
TDI
'96 B4V, '97 B4 (sold), '97 Jetta (scrapped)
The large side gets rotated CCW.

When I replaced the GP harness on a recently purchased Jetta, it was frozen. May never have been disconnected. Rotating CCW, broke one of the tabs on the engine side connector.

Support it with some large slip joints, if possible. I had to use them to tighten down properly, and it’s a tight area. I also used some silicone grease on the threads.

-Todd
 

specialed1995

Well-known member
Joined
Feb 1, 2015
Location
United States
TDI
1Z 1.9 TDI from 1996 B4 Passat
I've figured out almost all of the wiring on the ECU harness, but there are a couple connectors I can't figure out what they go to.


1st connector (4 way)

Pin 1 - T68/10
Pin 2 - T68/33
Pin 3 - T68/56
Pin 4 - T68/33

2nd connector (2 way)

Pin 1 - T68/27
Pin 2 - T24/9 (VSS Pin 1)

According to all the wiring diagrams I can find, ECU Pins 10, 27 and 56 are listed as "not used", so I have no idea what they are for.

Cleaned up the intake manifold a little bit yesterday by soaking it in a drain pan filled with diesel and scrubbing with a wire brush. It removed a good bit of the carbon, but it could still be better so I plan on doing it again tomorrow.
 

specialed1995

Well-known member
Joined
Feb 1, 2015
Location
United States
TDI
1Z 1.9 TDI from 1996 B4 Passat
Been a few months, but I've made some progress with the project.

Since I last posted, I've finished cleaning the intake manifold and also cleaned the intake ports on the cylinder head as best I could, making sure the valves were closed before knocking anything loose. I then blew everything out with compressed air and reinstalled the intake using the old gasket coated in copper spray on both sides (Was this a good idea?)

Also replaced the rubber fuel return hoses on the injectors with 3mm braided diesel vacuum hose. I purchased a new end cap for the last injector, but I've misplaced it and have to find it so I can put it on.

Removed the transmission ends on the Saturn axles so that just the splined shaft remains, hopefully that will make it easy when measuring the axles. That way I can just slide them where they need to be and weld everything up.

Purchased some 3/4 x 2 1/2 aluminum stock in order to fabricate the custom belt tensioner bracket for my serpentine belt setup that will bolt to the alternator bracket. Once it arrives I'll be working on that.

More work is still to come very soon. Would like to have a complete drivetrain that's ready to drop in by the end of summer.
 

Windex

Top Post Dawg
Joined
Apr 1, 2006
Location
Cambridge
TDI
05 B5V 01E FRF
I would get a new intake gasket - they are cheap, and compress during their one-time-only use.
 

specialed1995

Well-known member
Joined
Feb 1, 2015
Location
United States
TDI
1Z 1.9 TDI from 1996 B4 Passat
Got the serpentine belt tensioner bracket fabricated today, it looks pretty crude but the principle works. I turned the engine over via the crank bolt several times and everything seemed okay. In practice it remains to be seen whether it will work long term, but all tests point to good!

Will post side by side comparison of my application and jimbote's, who gave me the design.

Will also be purchasing a NEW intake gasket and installing it shortly, as it is much easier to change with the engine out.

Looking into doing the timing belt and water pump next, just another thing I'd rather get taken care of now rather than later on once I have the project car. As I've said I want everything as ready to drop in as possible before I get the car.
 
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specialed1995

Well-known member
Joined
Feb 1, 2015
Location
United States
TDI
1Z 1.9 TDI from 1996 B4 Passat
2019 Update

Sorry it has been so long since I've updated this thread (every time I post is beginning to start off like this:D) but this project is still ongoing.

Just recently I purchased a clutch kit and new flywheel (038198132H) and an ECU (028906021FA), two of the more expensive items on my parts list.

Still have to source a transmission, as well as a project car to put the drive train in, but I'd rather find the transmission first and have it assembled and ready to drop in.
 
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specialed1995

Well-known member
Joined
Feb 1, 2015
Location
United States
TDI
1Z 1.9 TDI from 1996 B4 Passat
I've just purchased a transmission (code CTN) as well as a new oil pan gasket. I'll also be purchasing a new rear main seal and replacing it before I install the new clutch and flywheel.

The valve cover gasket will be replaced when I get the timing belt kit. I've also got a new oil cooler seal that I will be replacing very soon. Any other gaskets or parts that you guys recommend be changed just as "preventative maintenance"?
 
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