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Mon Apr 08, 2013 12:45 pm

Rather than start a new thread, I changed the title of this thread, it was "difference between ABA and AHU/1Z oil pump?"

There seemed to be a lot of interest in this idea, so I'll keep it going. Last year Syncroghia started a thread on the idea of turning a TDi engine backward http://www.thesamba.com/vw/forum/viewtopic.php?t=515641&highlight=, I also had been wondering if it was possible. The TDi would have needed a custom camshaft to work. I am working on running an AEB backward, the advantage of this engine is the intake and exhaust cams are separate and I'm hoping I can re-time the timing chain and belt to open the valves at the right time running reverse of the norm.
I consider the AEB/ATW 1.8t and the ALH/1Z TDi engines a gift from VW. They allows us to mix a lot of old parts with much newer parts because they are based on the old engine blocks from the '70s, '80s, and '90s, yet they have much more modern cyl heads and engine managements. You can bolt a 1975 rabbit oil pan and transmission to either of these engines.

My goal is to run the engine backward using a B5 Passat 5speed transmission in a Vanagon. If this proves to be possible, maybe the A4/Passat Quattro/4motion transmission could be used in my Syncro?

My first question was "does anyone know the difference between these pump?"

Anyone know the difference?

Mon Apr 08, 2013 2:34 pm

I am fairly sure the shaft length is different but it's been a few years since I compared the two.

Mon Apr 08, 2013 3:17 pm

I'm trying to decide what oil pump would work better in an AEB (1.8t) block. I am attempting to run the engine backward. I am using a diesel gear on intermediate shaft and the gear from the vacuum pump to correct the direction of the oil pump shaft.
Any thoughts? I am trying to avoid removing oil pans from engines I have just to get the oil pumps out to try.

Andrew-

Mon Apr 08, 2013 6:38 pm

I spent a minute thinking on it. Now my head hurts.

Mon Apr 08, 2013 7:07 pm

That's nothing compared to the valve train and timing issues. This engine has separate intake and exhaust cams, this is the key that will allow it to run backward, or so I hope. I'm re-timing the belt and timing chain so it will open the valves at the correct time while spinning backward. The cam chain tensioner looks like it will be ok with reverse direction. I also will need to call #2 or #3 cylinder #1 and re-number the other cyls. accordingly and match the injector and coil wires to each. This is because of the location of the sensor wheel on the crank.
I'm hoping to correct the coolant and PS pump by running the belt on the other side of the pulley. I'm told the alternator will not care about direction of rotation.
The AEB oil pump is driven by a spline rather than a T slot like the AHU (bottom of the vac pump) or the AEB (bottom of the dist.)
My head really hurts.

Mon Apr 08, 2013 9:08 pm

Dayamn bud, I'm gonna need to spark one up before I revisit this topic again...throbbing migraine alert

Tue Apr 09, 2013 2:28 pm

I can't seem to shake this subject from my head. What solutions are available to correct the Bendix drive on the starter?

Tue Apr 09, 2013 2:35 pm

I'm hoping to combine parts from a Jetta starter with a passat B5 starter. They were mounted on opposite sides of the flywheel.
I could be making a complete fool of myself with this project but I've done that before.

Tue Apr 09, 2013 2:55 pm

So why are you running the motor backwards?

-Rob

Tue Apr 09, 2013 3:09 pm

Hoping to use a b5 (1998-2005) passat five speed transmission running backward as well in the back of a vanagon.
The transmission may have its own ideas on running backward.

Andrew-

Tue Apr 09, 2013 3:20 pm

Very cool idea.

Tue Apr 09, 2013 3:28 pm

But yet they still TURN the same way :wink:
xoo00oox wrote: I'm hoping to combine parts from a Jetta starter with a passat B5 starter. They were mounted on opposite sides of the flywheel.
I could be making a complete fool of myself with this project but I've done that before.
nothing reversed there, paint a direction arrow on the casing and hold up in each place. :idea:

Tue Apr 09, 2013 5:22 pm

The inline passat starter....

Volkswagen Passat Starter also fits these models:
2005::GL; 4Cyl 1.8L AWM;
2005::GL; 4Cyl 1.8L;
2005::GLS 4 Motion; 4Cyl 1.8L AWM;
2005::GLS 4 Motion; 4Cyl 1.8L;
2005::GLS; 4Cyl 1.8L AWM;
2005::GLS; 4Cyl 1.8L;
Part Name Volkswagen Passat Starter - New Click Image to Enlarge

Part #REPA320101
Brand Replacement
Fits 2001-2004 Volkswagen Passat
Features
Condition: New
Type: OE Replacement, 9-tooth Pinion, Clockwise Rotation, 1.4 KW Power Output, PMGR Design
Quantitysold: Sold Individually

The transverse Jetta/golf starter.......

Volkswagen Jetta Starter also fits these models:
2000|2001|2002|2003|2004|2005::GL; 4Cyl 2.0L;
2000|2001|2002|2003|2004|2005::GLS; 4Cyl 1.8L;
2000|2001|2002|2003|2004|2005::GLS; 4Cyl 2.0L;
2001|2003::Wolfsburg Edition; 4Cyl 1.8L;
2003|2004|2005::GL; 4Cyl 1.8L;
2004|2005::GLI; 4Cyl 1.8L;
Part Name Volkswagen Jetta Starter - OE Replacement, 10-tooth Pinion, Counterclockwise Rotation, 1.1 KW Power Output, PMGR Design

Tue Apr 09, 2013 5:53 pm

xoo00oox wrote: Hoping to use a b5 (1998-2005) passat five speed transmission running backward as well in the back of a vanagon.
The transmission may have its own ideas on running backward.

Andrew-

This is where I thought you were headed.

Having seen the involved great work D Clymer has done with the Suby transmission, I would imagine that the shift linkage for the Passat 5 speed is all doable. (?)

Neil.

Tue Apr 09, 2013 6:33 pm

Hi 'Nut, I'm sure we can work out the shifter, I'm not sure yet the engine will work. There may be some hidden surprises in store.

Tue Apr 09, 2013 9:25 pm

Aren't you going to have to cut apart the camshaft and reweld to make it open at the correct time? Seems like you would almost be better off running a Honda engine that rotates opposite from the factory.

Plus I don't know how well the ring gear is going to like the reverse load either. And would you have 5 reverse gears? Hurts my head trying to picture it.

I know it would be more expensive, but I would probably use a Porsche trans. It's already setup the correct way and sure to handle whatever power you throw at it.

Another option would be just to enlarge the rear seat firewall and run a mid engine setup with a stock Passat transmission and engine

Wed Apr 10, 2013 2:32 am

The reason for making it spin backward is so I don't have five forward gears using the Passat trans that is now mounted in the back of a van.
It's not about cost, I have a Porsche 915 transmission in my collection of parts. It's more about the challenge of seeing if it can be done, if it works out it should make a nice driving van.
I don't know how well the transmission will like it but I'm willing to sacrafice one to find out. My theroy is it will be fine because they are made to handle loads in both directions. Every time you let off throttle or downshift it reverses the load that the engine puts on to drive the wheels.
All the headaches this is causing is just a side benefit.

Wed Apr 10, 2013 4:32 am

Why don't you do the tranny flip ? Puts your shift linkage on the correct side.

Wed Apr 10, 2013 4:12 pm

Rallyedude wrote: Why don't you do the tranny flip ? Puts your shift linkage on the correct side.

-mostly because I want to see if I can make this work.

Libby was correct, the shaft is longer on the diesel pump. I going to try using the AHU/1z TDi oil pump and cut the base of an old vacuum pump off to keep the gear running true.

Wed Apr 10, 2013 4:58 pm

Another issue I thought of was the pressure on the timing belt tensioner. Instead of being on the mostly slack side, the tensioner is now the roller with all the pressure on it from dragging the camshaft along. A mechanical tensioner will have to be used but I don't know how long the bearing would last with that much demand on it.