Brett's '97 TJ VW 1.9L TDi Swap

[brett313]

Hey All,

I'm starting this thread as a build log for my TJ. It was originally a I4 2.5L engine all stock except a basic puck lift, No A/C and already been to the moon as far as mileage is concerned. I've been a lurker on and off for a while, and I used to be active on a couple other forums a long time ago. Going to post history of some of the pictures I have to the point where it sits now. My hope is this thread functions as a log for the work I've done, and to help some people out who have similar ideas along the way.

I bought this Jeep from OfferUp in February of 2020 as a birthday gift to myself. I had previously wheeled a 2wd Xterra all over Arizona and was looking for a fun project to work on. I originally wanted to purchase a Land Rover Disco II, but a friend found this posted within 5 minutes of my home and I bough it the next day.

Here's the first couple pictures I have of it, it was in rough shape. Hadn't been driven in a few years, and was parked outside for over a year with no top.

I was unable to get it even registered in the emissions control area of Phoenix, so over the next month i set to diagnosing what was wrong. Basically, it came down to needing new fluids, belts, replacing O2 sensors (using the help of this forum), and changing the aftermarket exhaust manifold back to an OEM manifold and downpipe setup, I ended up needing to change out the fuel pump because i was losing prime at every start. Theres no rust being a mostly AZ vehicle, but there is a large impact on the right rear end which i have yet to fix.

 

[brett313]

STAGE 1: GET IT OFFROAD READY

I bought this jeep to have some fun, so lets get it rolling!

After I passed emissions in Arizona for the first time since 2012! I needed to make some basic mods to get it roadworthy.

Shocks all over were completely shot. I mean toasted. I actually had a blast leaving it in first and feathering the skinny pedal. I could get the front end to completely bounce in the air.

I went with the ARB 2.5 inch HD kit to give me plenty of options down the road. I've been a big ARB fanboy for a long time since having their rear air locker and bumper on the old xterra.

The inside was disgusting, having sat outside forever. Lots of dirt, rotted wood from the previous owner and droppings.

Got out the pressure washer and went to town. Oh god, the PO did some crappy spray bedliner on the ENTIRE interior. Sadly its still that way for now, got to wait until STAGE 3 of the build to get there.

A lot of the time for the next few weeks was cleaning up and fixing issues the PO made. Lots of stupid decisions and weird sh*t went into this jeep at one point, I think its part of the reason I got it so cheap.



ANYWAYS, it was time for its maiden voyage to touch dirt for the first time.

 

[brett313]

I had some fun putzing around arizona, made a couple road trips to some various states, but the 2.5L is a DOG, thank the jeep gods it is atleast geared with 4.10s.

I got some new tires and finished almost finished welding up my bumper kit (almost means i'll actually finish it some other time, LOL). Drove it out to California to visit my parents. Open top for 8 hours in a the 2.5 is an experience.

I actually don't have a ton of pictures of this time, because i was having so much fun driving it. I made a trip to nevada, utah, and northern arizona, but by the time I returned, it was getting pretty hot in Arizona, and with no A/C it meant I had to take a break. I had a ton of trouble starting it in the high altitude of Flagstaff. At this point, I pretty much put the TJ on leave until it cooled off and I could get to STAGE 2 DUH DUH DUHHHHHHH.

 

[brett313]

STAGE 2: Anyone make a 0.6 L Delete kit?

Finally we get to the point where I start building the TJ how I want it and for what I want it for.

You see in May of 2020, I picked up a little friendly car with a blown automatic transmission. This little econobox, known to some as the Volkswagen Golf 1.9L TDI, has an amazing, reliable, simple ALH engine. The engine is timing belt based, overhead cam, and rotary injection pump fed. No lift pump or intermediary fuel rail required.

I never intended to buy this jeep for keeping the stock motor, in fact I had plans to do a similar diesel swap to the Disco II I was originally going to buy.

So you might ask, how could I pull out a still working, albeit last legs, engine out of my jeep in the middle of prime jeeping season in arizona (november 2020)? I literally dont know I just ripped the band aide off and got her started. Also picked up another jeep, a fairly mint 2007 grand cherokee with the 3.0L CRD engine. At least now I'd have my 4x4 fix in the mean time.

The dissection continues. Had a big head gasket leak in the 2.5, I think this contributed to the magical place my coolant kept disappearing to. The 2.5 short block will make a nice table, but that can wait.

 

[brett313]

So the TDI teardown of the VW took about 6 hours, and it took about the same amount of time to strip down the jeep. I have no sensible advice for this procedure, other than be very considerate of your wiring harness. On the VW the ECU small side connector can be completely removed out of the vehicle without any cutting, and you can keep all engine sensors and actuators hooked up to your engine.

The large side, there's a lot more wiring cutting involved. You need only need to keep the foot pedal harness, the n75 turbo actuator, Manifold Absolute Pressure Sensor (runs on vacuum with a grey top, not to be confused with the EGR actuator which has a black top), and stuff. You can also optionally include the Mass Air Flow sensor, and anti shudder valve and EGR, but I opted to not go with those for my setup. I also opted not to include cruise control which requires use of the clutch and brake sensor from the VW.

For the rest of this build. I'm going with the following upgrades/modifications:

Homemade truss type Engine mounts
TD conversions 1.9 to jeep 4.0 adapter setup
AX15 transmission
Tummy tuck
NP231 mega short SYE, change to 23 spline input to go from the AX5 21 spine, also added a heavy duty extra wide chain.
I'll need to pick up a new rear driveshaft once I get everything installed.


I'm in the process of finalizing my engine mounts. I need some big gussets and final welding of my new crossmember to be able to mount the engine in for good.

I'm also currently missing the correct external slave front bearing retainer for my AX15 so that's being shipped soon, and I'm neck deep in a timing belt and head gasket change on the 1.9 ...

In the mean time before I give any more updates, here's a teaser turbo wrangler pic, as well as some other random pics along the build.

 

[brett313]

As for now, the thread is updated until I can get some time to keep working on it next week. After engine is mounted and electronics are integrated, I still have a lot of plumbing to cover for the cooling system and the intercooler. Its awesome to be at the point where I get to start putting stuff together instead of tearing stuff down. The new headgasket and timing belt on the TDI will be that bridge. Feel free to give comments, criticisms, and questions!

 

[brett313]

I got the Standalone engine and harness started, I was not expecting the injection pump to have held its prime this well over the course of the last couple months, but it turned over immediately, I don't even have the glow plugs operating in circuit yet either.

 

[brett313]

Clearances the 4.0 bell housing for the new starter motor location. Not the prettiest, but it works, or at least it will self clearance . I may tig a small cover plate to prevent stuff from getting in , but there are so many other holes on the bell housing already im not sure it matters....

Does anyone know if the factory bell housing has plugs or covers to keep dust out or if that’s a common mod? Do you need the clutch area to “breathe” ? I know this is a noob question I’ve just never thought about it so bear with me

 

[brett313]

I made this super long, boring video discussing the wiring harness for the ALH with all the necessary deletions performed, hopefully if someone does a similar swap this video will help them out!

 

[Sea Cot]

Thanks for posting this project and detail. I'm hoping you'll stick around long enough to share experiences once you get it on the road. I'm really considering this swap for one of the Jeeps, but have zero experience with driving or maintaining any TDI.

 

[brett313]

So I wanted to catalogue my solution to the complicated cooling system on these ALH's and try to simplify what actually goes on between the back of the engine and the firewall of the jeep where there just isn't a lot of clearance. I made a few modifications to the coolant tube that serves as the coolant return line from the heater core, EGR cooler, auto transmission cooler and oil cooler in a factory Golf or jetta. For my setup, I only want to keep the heater core and oil cooler return line (the radiator returns on the thermostat housing)


On the passenger side of the engine, you can cut the coolant pipe back to eliminate the EGR cooler return. To eliminate the transmission cooler return line, I trimmed, and welded that area short.

I'm also including a dimensioned drawing of the coolant pipe/block interface piece which I may want to turn on a lathe in the future to rebuild a cleaner pipe out of stainless or something.

 

[brett313]

Thanks for posting this project and detail. I'm hoping you'll stick around long enough to share experiences once you get it on the road. I'm really considering this swap for one of the Jeeps, but have zero experience with driving or maintaining any TDI.

Hey thanks a ton for reading, I'm definitely going to keep posting through, I'm building this thread as a manual to myself as much as I am for trying to help others. The ALH is a great engine for those that are on a budget, and overall relatively simple with a few quirks.

 

[brett313]

Quick update for today:
Wanted to share the results of firewall side simplification, you can see the coolant return pipe tucks in nicely between the adapter and the block. Another thing I did was to change the rear coolant flange from the a MK4 style to a MK5 style (03G121132BE URO Parts). This eliminates and extra hose connection in the back side of the engine which is originally the hot side oil cooler input. This will be relocated to a 3 way adapter feeding out of the upper radiator pipe.

Also pictured is the TD conversions adapter, centerforce (woohoo made in AZ) high inertia flywheel and I went with a factory clutch for this one.

Another thing I’m trying out is an alternative way to delete the A/C and provide a little extra clearance on the driver side of the engine to clear the steering bracket.

this bracket holds the injection pump, belt tensioner, alternator, and VW power steering pump. Because this bracket holds the injection pump it would be a good idea to change it at the same time you are changing the timing belt. SKU: 038903143A-GEN

This is in contrast to the factory bracket which also holds the AC compressor and an extra idler. This is a more complicated AC delete than just a ac bypass pulley but it is much cleaner in my opinion. With the downside that they never offered this bracket for sale in any US market cars. You’ll need to find one from an importer or eBay. The belt is also a much smaller one 906mm (038903137G) instead of ~1660 mm belt

Overall I think this setup will provide a much cleaner install, new bracket pictured on right.

 

[brett313]

Alright, 80% done 80% to go!

Engine is finally mounted in place hopefully for the foreseeable future.

The mount I fabricated uses the Volkswagen pendulum type mount to mount an A type truss on a new crossmember that is bolted in to permanently welded mounts on each side of the frame. This is the method that cotybuilt uses on their engine mounting kit, but they incorporate a new accessory drive system within their mount.

I went with this style because it was easy, allowed a good amount of clearance for the busy driver side which holds a lot of coolant plumbing, accessories etc, and the also busy passenger side which houses the starter and exhaust downpipe. I left the crossmember as a two piece type because it gives me the option to build a new mount that directly bolts into the block in the future.

The engine mounts are two Anchor 2869 hydraulic\liquid style engine mounts, mainly because they were the cheapest type of hydraulic mount available and have consistently good reviews on durability and vibration damping.

Intercooler size fitting for infront of the radiator, I need a relatively small intercooler so I ordered an air to air Mishimoto Core and plan to build it up so it works for my application. I think a minimal amount of cutting will need to be done to the bottom inside area of the grill. The 1.25in body lift definitely helps clearance in this area.

I still have quite a bit of work left to finalize this swap, still need to sort out accessories like power steering and alternator wiring to battery, the lower radiator hose will be much easier than the top hose, and splicing into the jeep wiring harness to keep only the necessities. Stay tuned as i start crossing the stuff off the checklist hopefully before it gets too hot out here in arizona...

 

[808jeeper]

Love the build right up! I just picked up my donor car with a bew in it. Gonna be putting it in my tj 2.5l. Was hoping to get an ALH but here in Hawaii the tdi is rare. What’s left on original Jeep wire harness?

 

[brett313]

Love the build right up! I just picked up my donor car with a bew in it. Gonna be putting it in my tj 2.5l. Was hoping to get an ALH but here in Hawaii the tdi is rare. What’s left on original Jeep wire harness?

Hey 808, thanks for reading. Been struggling to make time on the jeep this last two weeks but I'll be hopefully wrapping up soon here.

BEW is a good engine, its a bit more complicated than the ALH, but can make more power easier. You are right in the other thread that Cotybuilt makes a harness for it. Because the engine is standalone on the ALH, really the only necessary connection between the original jeep harness will be the ignition cylinder.

I'll basically be keeping just the lighting, jeep interior accessories, and the window washer motor from the original jeep harness. I haven't worked into any of that side yet. I just want to get the alh running and driving before start deleting the jeep harness. I'll definitely post back on here the final wiring diagrams once I'm through all that.

 

[808jeeper]

Hey 808, thanks for reading. Been struggling to make time on the jeep this last two weeks but I'll be hopefully wrapping up soon here.

BEW is a good engine, its a bit more complicated than the ALH, but can make more power easier. You are right in the other thread that Cotybuilt makes a harness for it. Because the engine is standalone on the ALH, really the only necessary connection between the original jeep harness will be the ignition cylinder.

I'll basically be keeping just the lighting, jeep interior accessories, and the window washer motor from the original jeep harness. I haven't worked into any of that side yet. I just want to get the alh running and driving before start deleting the jeep harness. I'll definitely post back on here the final wiring diagrams once I'm through all that.

Definitely will be following. Yeah I plan on using the FFA harness i like the options they offer

 

[brett313]

Haven't been able to do any work on the jeep on account of the weather here in AZ and me not even having a garage to work in. That being said, when things die down for work in a month, my plan is to skip the intercooler for now and just run a direct feed from turbo outlet to inlet. It absolutely will not be ideal, but in the name of expediency and just getting things done it has to happen for now. I'm glad I made the big push to test the engine and get it mounted before summer

A few people in other places asked about my mounting setup, so I made a short video showing my semi-temporary front engine truss. Posting here if anyone is interested. I'm not sure how I feel about it overall, but I made it in multiple pieces so I can keep working on things if they don't pan out.

Still need to work on coolant system before I can test drive it. Plan is to run the factory jeep Rad with an electric fan. Anyone have a source on decenet electric fan? Then it will be power steering, driveshafts, and wrapping up all the wiring. I'm frustrated it's taking this long but that's the cost of not having a real shop.

 

[BugoutJeep]

So I wanted to catalogue my solution to the complicated cooling system on these ALH's and try to simplify what actually goes on between the back of the engine and the firewall of the jeep where there just isn't a lot of clearance. I made a few modifications to the coolant tube that serves as the coolant return line from the heater core, EGR cooler, auto transmission cooler and oil cooler in a factory Golf or jetta. For my setup, I only want to keep the heater core and oil cooler return line (the radiator returns on the thermostat housing)


On the passenger side of the engine, you can cut the coolant pipe back to eliminate the EGR cooler return. To eliminate the transmission cooler return line, I trimmed, and welded that area short.

I'm also including a dimensioned drawing of the coolant pipe/block interface piece which I may want to turn on a lathe in the future to rebuild a cleaner pipe out of stainless or something.


View attachment 244763


View attachment 244758

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I'm getting all caught, but you had me confused for a bit on your drawing because your zeros look like they signify diameters.

I really want to do a TDI build, but my needs are for a larger diesel build. I don't even trust a 2.8 to workout either for my needs, but I'm guessing to a point. In any case I worry that the narrow frame will make it difficult for me to get the necessary cooling for the smaller turbo diesels to pull my 6k lb camper and my trailer loaded to around 7k lbs total. I think and know the small turbo diesels will move a regular Jeep quite well. My build will be forced to have a similar wheelbase to a Tacoma and the frame, steering/suspension, etc will be beefed up to handle the towing duties.

In any case I must have been so busy with work that I missed your thread. I can't drive a vehicle and not think of a diesel swap opportunity.

 

[brett313]

I'm getting all caught, but you had me confused for a bit on your drawing because your zeros look like they signify diameters.

We don’t talk about those little guys

I really want to do a TDI build, but my needs are for a larger diesel build. I don't even trust a 2.8 to workout either for my needs, but I'm guessing to a point. In any case I worry that the narrow frame will make it difficult for me to get the necessary cooling for the smaller turbo diesels to pull my 6k lb camper and my trailer loaded to around 7k lbs total. I think and know the small turbo diesels will move a regular Jeep quite well. My build will be forced to have a similar wheelbase to a Tacoma and the frame, steering/suspension, etc will be beefed up to handle the towing duties.

In any case I must have been so busy with work that I missed your thread. I can't drive a vehicle and not think of a diesel swap opportunity.

Id personally not be comfortable towing that kind of weight behind a short wheelbase TJ.

I’d consider doing an OM606 (can make some POWER) or OM642( can fit into a tight spot, 450 ft.lb with a tune) swap into a 4 door jk frame if I were in your position that’s if you really wanted to keep it in the wrangler lineup, just nix every electronic component that comes from Jeep. But chrysler had electrical problems there too.

Jeep did make the 07-08 grand Cherokee in the Mercedes om642 3.0 CDI which if you have the real transfer case and locking axles can handle itself okay. tow rating up above 7000lbs

I’ve also looked at the early-mid 2000’s tundras as potential swap platforms, I’m a big fan of those trucks and their style but it’s all about what you want to get out of it in the end. I love IFS for mild off-roading and forest service roads, but I just wanted a road trippable TJ to putz around in and get to awesome spots.

So many options nowadays and the brand new gasoline engines are getting awesome efficiency IMO it doesn’t always make sense to move to a diesel unless you are throwing it into an older vehicle.

Thanks for reading!