Build '95 4runner TDI swap

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The 4wd gets real simple when you rip out all the vacuum engagement stuff and install locking hubs.

The only vacuum necessary at the point is the n75 system and brake booster.
 
I was planning on switching to locking hubs eventually. I'd like to make the vacuum thing work for now. Is it as simple as applying vacuum the the hose coming from the axle or do I need something else?
 
Need to modify the ADD locking actuator so the front axle collar stays locked. Or find a 1st Gen who's doing SAS and steal the entire front carrier. I've had one for sale (4.10) for sale locally for 100 bucks for years on Craigslist and haven't gotten so much as a spam email on it. They don't seem to be good sellers.
 
I have been reading and I think that If I put vacuum to the line/hose going to the ADD it will connect the axle together. So all I have to do is connect the old vacuum switch to the axle and a 12v with a switch in the cab and it should work until I decide to change things up.

Im not sure this is correct but I couldnt find any other descriptions how the front axle lock works. I am going home tomorrow and will be able to read through my manual.
 
I realized that the manual is on my computer :facepalm: It looks like 19.69 in of Hg will do the trick.
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I'm not sure if it was on a yj, xj or 2nd Gen 4 runner, but I remember pulling an actuator for a repair on someone's front axle and they simply slid the lock fork into lock position and installed a hose clamp on the actuator rod so it couldn't collapse back into the unlock position. Simple yet effective.
 
That seems like it would work. I don't think it has a preferred position. It gets slid to one side by applying vacuum and to get it to go back you need to apply vacuum to the other side. Since the hubs are always engaged everything always turns so I don't know why they even bothered with disconnecting the drivers side axle. Maybe it handles better on road? My next major rebuild with be to the drive train.
 
Before locking the actuator it I'd install locking (unlocking hubs) to prevent unnecessary wear.
 
I'm planning on making the actuator work with a switch in the cab so I wont need locking hubs yet.

I pulled the wiring out and started to re think where everything is going to go. I ended up making an ECU bracket in the engine bay. It's made from scrap and I ended up cutting it up and rewelding it twice so it fit correctly. I'm planning on using Velcro to stick it to the mount...that with the connectors and it should be somewhat isolated from vibration. After its finished I'll make a heat shield - splash guard.
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mountainhorn said:

Toyota TDI 4Runner Project - Diesel Conversion

Documentation on installing a VW TDI diesel engine into a 1990 Toyota 4Runner 4wd
tdi4runner.blogspot.com tdi4runner.blogspot.com

This dude put an alh tdi in a 4runner and has quite a few write ups and videos.
Click to expand...
Thanks, that is a lot of good information. I'll read through it and finish his videos this weekend. Every conversion I see does things similarly but finds different ways to solve the problems that keep coming up.
 
There's no shortages of issues. My biggest gripe is my set up eating synchros. Longest I've gotten on a new set is one year before 2nd started giving issues. I keep a spare trans ready to go at all times.
 
I have a spare trans in my garage now. I was going to grind this one into the ground before swapping.

I mounted the electrical stuff under the hood and it all fit and has good access. I have no idea how I would have fit it under the glovebox. Everything fit and laid out with out a problem I wish I could get the fuel pump relays inside the cab but everything else seems to be weather sealed.

The pictures suck but everything fit where the fuel evap container and vacuum switches were.

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Looks good dude! When David asked me for wiring dimensions I told him make everything as long as possible. Always easier to make something shorter.

I also cheated and cut a hole close in the inner fender well close where your windshield wiper motor is located. I wanted all the relays and ECU under the dash or in the passenger kick panel where the original ECU was mounted.

I ran wiring out the rubber body boot the directly back into the engine bay
 
Everything I have in the engine bay is sealed except the relays for the fuel pump and the engine fan. I will probably end up switching them for sealed units
 
None of my AC compressor/horn/led headlight harness or electric fans have the rubber boots on the relay bases to make them "sealed".

I put a little electric grease on the prongs before install and I don't think I've ever had one fail.
 
I finished the hard part of the exhaust and did some wiring. I wrapped the exhaust where it runs close to wires or brake lines and have it supported from the turbo by building brackets to that bolt to the engine and transmission. I figured that they would move in unison.
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I also did some wiring also. It took a little while to rewrap my head around what I needed to do. I connected the starter motor and the fuel pump and got constant power to the ECU. It turns over but the fuel pump isn't running when I first turn on the key. I don't know that I connected the fuel pump relay correctly and don't really know how to check. I think that it should run until there is pressure in the line (I thought that was the reason for the double relays) I put 12v to the ECU, connected all the sensors, and ran a wire from the fuel pump to the relay.

The engine turns over but didnt fire. I am going to trouble shoot the fuel pump relay tomorrow and see if it starts. Any advice or things to look for is welcome.
 
It should turn on for a moment when you key switch on. A PD will take a while to prime when dry.

Verify fuel pump function. You can use VCDS to run fuel pump instead of relying on key.

Once the fuel pump verified running pull the glow plugs. Turn the engine over until you see fuel mist coming from the holes. Reinstall and it should fire easily.

I should add, running down the battery during priming process is common. Whenever possible I put a jumper box on the battery during all the long 30-45 second start cycles
 
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