Tuesday, March 8, 2016

1997 Eurovan T4 EVC AHU TDI and 5-spd manual trans conversion COMPLETE

This sweet 1997 EVC is in the shop right now moving on from its VR6/auto trans past and into the passing lane with a AHU TDI eng and a 5-spd trans conversion.  Here are some pics of this project currently underway during Feb/Mar. 2016.  Please stay tuned for updates as this project is under a tight deadline (Mar. 21), so blog updates will be posted as time permits:

UPDATE 4/11/16:  

This project was completed and picked up last week and is currently in the engine break-in phase.  After 231 miles of test driving the only issue that came up was a small coolant leak in the upper radiator hose at the AC cutoff switch fitting.  This was resolved easily and sent on its way.  We schedule another check in and fluid change at 1000 miles to catch anything else that is materializing and make sure the fluids are all top offed.  Here are some pics of the final phases, test driving and badging:

1997 Eurovan T4 EVC TDI and 5-spd trans conversion

1997 EVC gas VR6 engine Automatic transmission

Initial intake: fluids are drained; eng oil, coolant and power steering fluid

AHU engine rebuild:

After engine work is finished at machine shop, it is mounted to rebuild stand and first painted with a few coats of engine enamel. 

Piston cooling jets.  Installing these is the first internal step in the rebuild process.

Next rear main bearings are installed in block along with intermediate shaft (new I-shaft bearings done at machine shop)

Polished crankshaft and main bearing caps ready for install.  New ASV pistons awaiting installation.

Main bearings, thrust bearings and main bearing caps.

Main bearing page out of Bentley play book...

After crank is laid the radial clearances are measured in situ with Plastigage.

All within spec, so Plastigage is cleaned up, assembly lube applied and main caps positioned in the proper position and then new TTY main cap bolts are installed, torqued to 48 ft/lbs +90*,

New main bearing bolts.

ASV pistons.  Note oil cooling galleys cast into piston crown.  These are where the oil squirters spray their stream.

Top of ASV piston.

Reconditioned rods laid out with new rod bearings installed and new rod bolts awaiting installation.

Crank positioned for installation of #1 and #4 pistons, done 2 at a time and rod bearing radial clearances measured with Plastigage.

Rod bearing page out of Bentley play book.

All within spec!

Pistons installed and new TTY rod bolts torqued to 22 ft/lbs +90*

Fully rebuilt cylinder head degreased and ready for install.

Proper thickness head gasket installed (3-notch in this case).

ARP head studs ready for installation.

Torqued in 3 even stages up to 125 ft/lbs.

New water pump and 87* C thermostat being installed.

Eng peripherals being added.

Oil cooler upgraded with V6 Passat oil cooler

K03/04 turbo mounted and clocked

Rebuild inj. pump by DFIS in PDX.

K03/04 compressor housing clocked 180*

K03/04 compressor housing clocked 180*

Pre-turbine EGT probe in exh. manifold. 

Gasoline fuel tank modifications to diesel

Step 1: fuel tank removal

Fuel tank straps.  Removed during tank removal process.

Stock fuel tank removed.

This pile of dirt at the top of this pic all come off of the top of the tank.  One dirty day....

Step 2: gas filler nozzle reducer removal

Filler nozzle reducer/flap.

3 press down tabs are what hold this in place. Tabs are lifted and filler reducer tapped off of filler neck.

Filler neck sans fuel cap attachment band/reducer

Fuel cap attachment band reinstalled sans filler reducer, allowing for use with diesel filler nozzles.

Tabs being re-tapped to hold terminus cap in place.

Step 3: Gas fuel level sender/pump removal 

Note orientation of fuel sender in/out before removal.

Removing fuel level sender/gas fuel pump

Fuel level sender/gas fuel pump removed and tank thoroughly drained and cleaned.

New diesel EV fuel level sender at top and old gas fuel level sender and pump combo at bottom.

Step 4: Fuel level sender/pump plug (4-pin) mod for diesel fuel level sender (2-pin)

The stock 97 EV fuel level sender plug has a 4-pin plug  (T4), with the two outer pins (T4/1 and T4/4) being the +/- for the fuel pump.  These are deleted from the circuit.

Terminal removal tool in action.  This is used to remove electrical terminals from their factory plugs.
New fuel level sender has only 2 pins, for the level sender only.

Original fuel level sender had 4, including the 2 for the gas pump.

This 2 pin plug will be used to make this a factory--esque install.

Plug shown empty, without any pins yet installed.

Pins being installed.

Wire secured and level sender being tested.

Step 5: Reinstall sender and reinstall tank

5-spd conversion: 

shift linkage re-build/restoration

EV 5-spd shift linkage.

Refurbished 5-spd shift linkage with all new bushings and surface cleaning/lube.

Shift linkage installation:
Former home of the auto trans shifter linkage, and the new home of the 5-spd shifter box/linkage.

5-spd shifter box installed and linkage to follow.

5-spd shifter level viewed from cabin.

Clutch pedal / hydraulics installation:

Manual trans brake/clutch pedal pin top, auto trans brake pedal pin bottom.

Alle sind in Ordnung aber etwas ist vermisst!

Clutch slave cylinder mounting, part of the stock A/T pedal cluster.

New ATE clutch master cylinder.

New OE clutch hydraulic lines/connector and master cylinder.

The stock VR6 cruise control vacuum hose is removed and this is the firewall hole used to install the clutch fluid hose enroute to the master cylinder.

And just next to it is the hole for installing the upper part of the clutch hydraulics.

Lower part of the clutch hydraulics including connector, hydraulic line and slave cylinder.

Blue hose is the clutch master cyl fluid feed line.

New pin installed and factory clutch pedal installed.

Accelerator pedal mod and potentiometer install

A3 Jetta pedal L, EV pedal R

End cut off of A3 Jetta pedal and EV pedal shortened.

Jetta end welded to EV pedal.

Jetta end welded to EV pedal.


EV/VR6 cruise control vacuum servo bracket to be removed, rivets drilled out.

Vac. servo removed.

Custom pedal pot. bracket.

Custom pedal pot. bracket.

AHU pedal potentiometer (pot, i.e., "Drive by Wire" module).

Custom pedal ver. 1.1

Custom pedal ver 1.1.  This turned out functional but a little short so was pulled and configured.

Ver. 2.2: lengthened pedal shaft approx. 40mm to get proper alignment with pedal pot. 

Checking throttle position % with VCDS, 0% at rest.

And 100% when pedal is fully depressed.

AHU Wiring harness mods:

AHU harness after factory tape was painstakingly removed and any unnecessary wires removed.

This end of the harness is what goes through the firewall and connects to the EV fuse block, etc.

Lengthening 2 circuits: G70 MAF and N79 PCV heater.  These must be lengthened when factory EV ECU mounting location is used for the AHU ECU.

Mods underway.

Mods underway.

G70 MAF and N79 PCV heater wire extension ID chart.
Modified AHU harness completed.
Stage II Malone tune being performed.

Closeout from VWoA, a NOS FA ECU 2004 production year, socketed and chipped with Malone stage II tune inside.

All B+ and Ground connectors at battery buffed/polished to remove corrosion, smeared with di-electric grease and reinstalled.

Relay block plug info for the 97 T4, page X44 EV Bentley.
Example fuse block from A3/B4/T4 generation showing plugin locations of engine harness plugs.  
Fuse/relay info for the 97 T4, page X40 EV Bentley.
Wires sorted and fuse block reinstalled.

Instrument cluster and instrument cluster wiring

B4 Passat TDI instrument cluster wiring. One wire out of the 28 white wires going to the instrument cluster must be modded for the B4 cluster to work in an EV.

B4 Passat TDI instrument cluster.  This is a bolt in cluster to all 97 and earlier T4s with a AHU/1Z TDI eng conv.

B4 Passat TDI instrument cluster installed in EV/T4.

Final install with trim

Front mount intercooler system (FMIC):

A new 3-grill T4 is born.  Behind this lower grill is the location of the intercooler and the inlet location for pos. pressure ambient temp. air.

2.25" intercooler mounted behind bumper skirt.

Close up of intercooler. A/C comp to be installed once engine is installed, keeping system sealed and refrigerant in situ.

IC final plumbing R side.

IC final plumbing L side.

Coolant system:

The cooling system of the 4cyl TDI eng is vastly simplified compared to the VR6 cooling system.  The high temp AC cutoff switch is maintained in the upper radiator hose via a custom sensor port and modifications to the ABL upper radiator hose.  

Lower radiator hose from ABL T4.

Clutch system

The clutch/pressure plate/flywheel used for the 02B 5-spd trans is basically the same as the ones used on the donor AHU TDI engine.  At some point in recent years the VW parts system updated this clutch/pressure plate to be the same as the early 90's G60 Corrado so these are components are  synonymous.  In this case a new AHU flywheel and new Sachs G60/AHU clutch kit were utilized.  This critical step is the last step before eng / trans mating and then assembly installation in vehicle.

New AHU Sachs clutch kit and flywheel

Bell housing dust plate installed on eng.

New bolts pressure plate bolts and new flywheel TTY bolts.

Flywheel installed and bolts torqued to 44ft/lbs + 90*.

New Sachs clutch disc.

Clutch alignment tool #VW 97 used to align clutch disc while pressure plate is torqued to spec.

Final stages 4-cyl TDI eng/5-spd DUJ trans installation:

This part of the conversion is currently underway now (3/29/16).  Time is limited and not many pics are being taken to expedite the process. Engine and trans were mated and engine timed at that point (easier to find TDC with bell housing view port), filled with oil and eng oil primed.  Then final prep was made for installing the eng/trans assembly into the van and this was done by sitting them on a high dolly and then lowering the van down onto the engine, then attaching the nuts to the L and R mounts.  The trans rear mount was done later once the eng/trans was freely hanging on the L/R mounts.   At this point there are a lot of things to take care of some of which are sequential and to simplify I break these down into systems:
AC system
Alternator system
Power steering system
Serpentine and V-belt
Coolant system
Fuel supply/return
Intercooler / turbo plumbing

Time for a few pics:

Eng/trans on tall dolly for installation from below van.

Van being lowered down onto eng/trans

Alignment is key :-)

R side eng mount lining up with frame mount ears.

AC compressor and alternator installed w/serp belt, and water pump pulley and PS pump w/ V-belt installed.
PS hoses attached and system filled.

Front/center view from below.

Vastly simplified custom 4-cyl coolant system final and being filled with G12 coolant.

View from below frt L

Misc. upgrades/maintenance

Stock EV/T4 alternator w/non-clutched pulley.

AHU clutched pulley to be installed with alt. pulley install tool.

AHU clutched pulley installed on 120A EV/T4 alternator.
Alternator dust shield removed to R&R voltage regulator.

Old voltage regulator, with brush length getting critical.
New Bosch voltage regulator.

Bentley carbon brush limit spec: 0.5mm

New voltage regulator comparison with old one.
New voltage regulator installed.

New voltage regulator installed.

Battery ground cable L showing signs of excessive corrosion; new OE VW one right.

New battery ground cable L and old one R.

New Bosch S5 starting battery.

Factory diesel T4 fuel filter location, front L corner of vehicle in front and below battery.

Upper ball joint R+R

Upper ball joint R side being removed.

R side upper ball joint removed.

New upper ball joint being pressed in.

R upper ball joint installed.

R upper ball joint installed.

Circlip for ball joint.

Upper ball joint removal/install tool from Germany.

New upper ball joint and new sway bar link R side.

New upper ball joint and new sway bar link R side.

Old L side upper ball joint showing wear.  

New upper ball joint L side installed.

L side installed with attached to wheel/brake hub.

T4 Bentley archival info, upper ball joint R&R.

T4 Bentley archival info, upper ball joint R&R.

Sway bar links R+R

New sway bar link L side.

New sway bar link R side.

Sure Power Battery Separator upgrade

Stock Winnebago house battery solenoid and 40a breaker.   Ign+ (15) on and the house batt. is connected to the starting batt.  This is also basically the same solenoid as used on a 1967 Ford pickup truck starter solenoid...

Detail of aux. batt. solenoid.

One more overview of the area and then these components are getting upgraded.

New Sure Power 1315A 100a battery separator.  This is relatively "smart" and only connects the two batteries when a preset voltage is reached (13.7v IIRC).

Sure Power 1315A and new 40a breaker fitted, ready to be wired.

Wiring complete w/breaker protective cover.


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