Custom Exhaust Manifold is Finished

Yesterday I completed the build of my custom exhaust log manifold for the 4Runner. The flange is 0.50" steel and so is the flange for the turbo. The tubing is 1 1/4 schedule 40 pipe. I used 4 90 degree elbows and 2 45 degree bends, plus a few straight sections of roll bar tubing left over from my Mustang project. The roll bar tubing turned out to be the same thickness and diameter as the pipe, so that worked out great. I TIG welded the entire manifold while it was bolted down to a spare cylinder head. End result was a flat flange and good penetration on the welds. After all the welding was complete, I used a carbide burr to clean up the port inlets and outlets in hopes to remove any flow-impeding edges, etc. Not sure how much that will matter on this application, but I do know it won't hurt.

I also built a bracket to brace the manifold to the block. The turbo is pretty heavy, and the manifold will hold a lot of heat. Nearly all factory turbo setups are braced to the block, so I am hoping this will help to prevent any future issues. I only want to build this once!

The bends are lightly tacked in place just to get the project started.

It is kind of like a puzzle.. there were known angles I had to have, and then I just had to fill in the missing pieces.

I still am surprised at how this turned out! I used a sharpie and a cutoff wheel to cut the two 90 degree fittings to merge them into the collector. That was some pretty precise eyballing right there :)

All the tubes are notched and fitted reasonably well and tacked together.

Nearly all welded up.

Bolted to the spare cylinder head - keeps the manifold from warping when welded.

That is the support brace tab on the bottom of the manifold.

Support brace - it's not very pretty, but it'll definitely do the job. I did not have a long enough piece of flat steel on hand, so I had to use a portion of round pipe to make it work.

This is how it all sits in the chassis.

Everything is bolted down on the engine - even installed the gaskets! Hopefully I won't be taking this off again any time soon.

Wiring mostly done & ECM is working!

I have spent the last few weeks working on the wiring harness. It really isn't all that complicated. The level of diagram comprehension has to be high in order to properly adapt necessary circuits and remove others. Thankfully, I have the early ALH engine, which only has an 80 pin ECM instead of 121 pins!

I started by printing the diagrams so I could color code some circuits and write notes. Next, I identified battery power, switched power, ECM grounds, etc. After I throughly understood the factory setup, I was then able to draw up my own power distribution diagram & fuse block.

Today I made lots of progress with the wiring adaptation. End result is the ECM powers on with with the ignition switch, sensors are powered, and I can read codes and the datastream with an OBDII scanner! The part that surprised me is that it all worked the first time I put power to the system once it was all connected. :) The key was lots of research up front to ensure I fully understood the function of each wire.

Yesterday I jumped power to the starter solenoid with the Power Probe, and the engine turned over without any issues. Glad to see the factory Toyota starter & ACME Adapters flywheel are working well together. There's been no reports of issues, but it was nice to see mine worked properly. :)

Next big step is to fabricate the exhaust manifold. I am hoping to create a tri-y style header similar to the one found here. I think I will have enough room. The manifold will be created from schedule 40 weld els and 1/2" flanges.

Murphy's law of automotive wiring: if you make it all neat and tape up the harness before you throughly test it, it will be wrong and you'll have to untape it & start over! Now that it works, I can fully secure a few temporary connections and then clean up the harness.

I'm going to put the battery on the driver's side. The air filter needs to be on the passenger side fender well due to turbo placement. In this picture, I have the the battery charger, power probe, and multiple jumper wires attached to the battery. Most of that is for testing purposes & will be eliminated once all is more permanent. Keeping a battery charger nearby & maintaining full battery voltage is critical for proper electrical system testing & functionality.

This is the power distribution diagram I sketched out and is similar to the VW track style diagrams (which I really like!). Power comes in from the top and output & grounds are towards the bottom. Solid orange is B+ at all times. Hashed orange is switched B+. Yellow is ground. Penciled circles at the bottom tells me what wire &/or circuits this fuse is powering on the factory VW wiring harness.

Functioning fuse block and OBDII connector. Power enters the bottom of the fuse block and exits to different circuits and components at the top.

 

Dusted off the Lincoln Precision TIG 185 !

I haven't TIG welded in almost 2 years.. finally got a new tank of Argon yesterday. Tonight I did a quick practice butt weld with some scrap roll cage tubing. Beveled each side at 45 degrees and then did a 2 pass butt weld. I surprised myself! Soon I should be fabricating the exhaust manifold for the TDI 4Runner. Tentative plan is a tri-Y style header, but we'll see if I have enough room to do that. Going to be tight.

Working on the ECM wiring harness

In the last few days I have starting working on the wiring. This means spending many hours studying the diagrams, figuring out exactly what each wire does, is it important for the Toyota swap, etc. It's not terribly difficult, it just takes a lot of time - at least for me it does! Luckily my donor car was a 99 Golf, so the ECM is only an 80 pin, and not the 121 pin from later years!

I am hoping to order some schedule 40 weld els tonight so that I will be ready to fabricate the exhaust manifold soon. Not sure yet if I will TIG or MIG the manifold, but leaning towards TIG. More on that to come when I get to that step.

I believe that once the wiring harness is finished and the exhaust manifold is finished, the project will easier to make progress on. At that point it will be lots of small things to do and less major issues to work through.

Flywheel, clutch, & starter is Installed

The clutch kit came in yesterday, so I pulled the engine back out and installed it last night. It turned into a bit of a job because of the way the engine is oriented. I have moved the lift chains all around and worked with the load leveler, but still can't quite get the angle correct - it is a job to get that engine to line up and bolt in! The flywheel, clutch, pressure plate, and throwout bearing installed with no problems. I manually turned the crank and the 4Runner moved forward, so that's a good sign!

Today I installed the starter. It is a high output gear reduction starter for a 98 3.4l Toyota Tacoma. It fits perfectly when installed with the spacer plate supplied with the Acme Adapters kit. I did have to drill out the threads on the lower starter mounting hole so the bolt would thread into the bell housing. 

I also installed the clutch slave cylinder - the pedal has a very nice feel and is not too heavy at all. Feels about like a stock TDI Jetta Clutch. 

I made a mistake when fabricating the engine mounts - the driver side mount is too close to the AC compressor. It lightly hits the center of the AC pulley. This is not the end of the world since I was not going to run AC at first. The center of the pulley only turns when the clutch is engaged. I should be able to fix this fairly easily - I'll just notch the mount holes and move the mount. I only need about 2 or 3 mm to clear the AC clutch.

Acme Adapters did their job - alignment looks dead on!

The driver's side motor mount is a bit close to the AC clutch - needs some adjustment!

Engine mount for TDI is done!

This weekend's project was to fabricate the engine mounts for the TDI. I ended up changing my plans some as I went along, but it turned out great - I am very happy with the results! 

I welded a 2" box tube between the frame rails to hold the motor mounts. I am using the factory VW B5 Passat 2.8 V6 hydraulic mounts. They are affordable and should do a good job. Time will tell how well they work, but by moving the engine around by hand, they feel similar to stock VW TDI mounts in a Jetta.

I connected the mounts to the engine by making a brace. It's a similar idea to a motor plate in a race car. I bolted the brace to the existing factory VW bracket on the front of the engine. The round pipe you see in the pictures below is some left over roll cage tubing from my previous Mustang project. This mount/brace is probably overbuilt, but that's better than being inadequate.

In other news, my clutch should be here either tomorrow or Tuesday. I ordered an F1 Racing Stage 2 clutch. The next level up was a 6 puck ceramic clutch, which I do not want for a daily driver. I did not find anything better, so I'll give this a try and hope for the best. 

I also ordered a 1/2 thick laser cut exhaust manifold flange; soon I will be ready to start fabricating the log manifold.

My welding isn't as good as it used to be - I haven't welded in the last 2 years, so I'm a bit out of practice. It'll come back to me soon, though.

First VW TDI test fit in the Toyota 4Runner

Since I finished the transmission lift mount yesterday, I decided to go ahead and do a test fit with the engine. Took a while to get the angles just right for the adapter plate dowel pins to drop into the bellhousing, but it finally dropped into place. I secured it temporarily with 2 bolts. After moving the engine around a bit and measuring to center the engine, it appears there will be enough room all around to fabricate the necessary parts. The oil pan clears the front differential by 0.75" and I can even bolt on the facotory VW AC compressor (will have to trim a corner off the old motor mount plate). Next to do is fabricate the engine mounts. I have a plan ready to go for that, just need to get a bit more material to work with.

Transmission lift mount is finished / What clutch?

Tonight I finally got the transmission lift mount welded in place. I had to lift the transmission 2" to get the engine high enough to clear the oil pan. I hope it doesn't cause issues with the front driveshaft angle, but we'll deal with that if it becomes a problem. Next step is to test fit the engine again to see if I have enough clearance. I think so, but it will be close. If the oil pan clears the differential, it will be time to start fabricating the engine mounts.

If anyone has a suggestion on what clutch to run, please talk to me! In order to get a clutch that will handle the torque of this engine, it will have to nearly be a race clutch. That's not ideal for a daily driver, which is what I'm hoping to have with this vehicle. Any ideas?

Removed V6 Toyota Engine

Early June, 2012 - I created a video of the old engine running before I pulled it out of the vehicle. The plan was to sell it on Craigslist to someone needing parts. As it turned out, that's exactly what happened - I sold the whole engine and all accessories for $125. Got them out of my way, better money than the scrap metal yard, and it helped someone else out.

Purchased 1990 Toyota 4Runner

May 17th, 2012 - Another Craigslist find - a 1990 Toyota 4Runner, 4WD, V6, 5sd manual transmission with a bad engine. Perfect! That was exactly the vehicle configuration I needed for this project. It had a bad engine with some internal damage. Not sure exactly what was wrong, nor did I care. Had to put it in 4 low just to have enough power to drive it on the trailer. It's about a 30 footer - not pretty and needs some body work and paint, but I'll worry about that once the new diesel drivetrain is working properly.

Assembling the Engine

March 2012 - After throughly inspecting and cleaning each component of the TDI engine, I started reassembling. I found a used complete cylinder head in good condition on a VW forum for a good price. Of course, I used new gaskets everywhere. Assembly was pretty straightforward; no surprises. Still have a few minor things to do later, but it is 80% ready to go. I did not seal the oil pan as I was worried about clearance issues in the 4Runner. I later confirmed my suspicions - the oil pan does his the front differential. This will be addressed in a future post.

Purchased a used TDI Engine

January of 2012 - I was doing my near-daily search on Craigslist for interesting stuff. I happened to see an ad for a VW TDI ALH engine from a wrecked car. I wasn't planning on starting this project any time soon as I had just purchased a business 3 months prior. Anyway, I scored the complete engine minus turbo plus the wiring harness and ECM for $900! It was only 1.5 hours away, so didn't take too long to pick up.

The engine was not ready to fire up, though. It had around 215k miles on it. Not sure why, but the engine had cylinder head problems. Appeared to have overheated a few times, but hard to say. Several of the lifters were cracked and damaged. One lifter had more or less disintegrated and severely damaged the lifter bore and camshaft. This engine would need a new cylinder head.