Former VWDieselParts.com Forum

I hope to post the tale of converting my 1971 VW Camper over to a turbo diesel here. We'll see how much I post...

I've been considering this conversion since ~2000. In the winter of 2004/2005 I found a donor engine on thesamba.com: a 1984 Jetta TD with 276k miles on it for ~$350 or so. Strong runner, but needed motor mounts, body work, suspension work, etc. Seemed like a good candidate.

I drove it from Philly to Baltimore (~100 miles?) and the oil light/buzzer came on a couple of times, but after checking the water temperature and oil level, my friend and I suspected a bad oil pressure switch.

Progress in 2004/2005:
Pulled the engine, tranny, and important bits and cut up the front end a little to do it. Had the body junked after offering it up on thesamba.com to no response. Broke off the vacuum plate valve in the process of pulling the engine.

Progress in 2006/2007:
There wasn't much progress between 2005 and 2007, as I moved, was busy with work, life, and trying to keep my other VW Bus on the road.

I purchased a vanagon oil sump and bellhousing, but determined it wasn't going to work for my purposes. This and other issues made funding the project an issue.

I did make some progress on the VW bus itself though: wheel bearings, minor body work, etc., which was all a necessary part of the process.

Progress in 2008:
Started to get rolling again. Picked up a Kennedy Engineering Adapter plate. Cleaned up the engine. Started reading up again and planning the motor mount.

Progress in 2009:
Changed the timing belt. Adjusted the valves (hopefully successfully), started work on and finished the motor mount with help from a friend.

Got stalled again on body work, but got the engine hung, the radiator located/mounted, etc.

Had some problems with starters, although at the end of the day it might have been a grounding and/or bad battery situation, which is very annoying given how easy a fix that is and how much time I spent on it.

Cut down the head-outlet-to-heater water flange so that the engine would fit and the heater would be usable.

Progress in 2010:
Installed a new block heater once I determined the old one was leaking.
Worked with flexible hosing to get everything plumbed, and it appears that everything is leak free at this point. I will probably work with metal materials once everything is running, but best not to get ahead of myself.

Finished body work with the help of a friend, at least in the "welding and grinding" and structural aspects. Still need to do beauty work.

Installed the new Kennedy high torque starter. Got engine to turn over but not start. Turned on the block heater for a half an hour and afterwards it sounded like it wanted to start, but wouldn't catch.

Nothing is really wired up on the engine yet, save for the IP solenoid cut-off and the temp gauge. Meaning: no glow plugs. That's my next step, and I've printed out various posts from vwdieselparts.com as well as the web in general on how to pimp my 'plugs. I'm definitely just going to leave the relay in the engine compartment and run an LED to the front so I know what's going on. I'll probably do a solenoid too, but baby steps.

Similarly, there's no radiator hooked up yet, I just have it bypassing using the flex hose (same as if the thermostat had not yet opened).

So tonight, I'll hook up the glow plugs. Let the block heater run for an hour or two, then see if she'll fire up. There's plenty of other stuff to do if she won't, but I just hope I didn't screw up adjusting the valves somehow. Might actually put some more diesel in her too, just to make sure there's enough gravity pressure and she's getting fuel. I can see fuel in the line past the IP, so I know some is getting through.

Oddly enough, when I hook up my idiot light to the oil pressure switch on the oil cooler, it doesn't ground and light up, even though I can ground to the switch using the battery. Must be too much resistance to light it up compared to what the stock sender would send, but that's surprising given they're both VW sensors and I think they're operating around the same pressure range.

I'll have to test that out later.

In other news, my generator/alternator light isn't working either and I'm not sure why. Suspect a bad bulb, or that I'm using the wrong wire, but it's tough to track down.

Woo-Hoo! We have first fire! As could have been expected, a hot block and well maintained glow plugs did the trick. Two hours on the block heater, hotwiring the glow plugs for 12 seconds, then turning it over with the throttle wide open ( as posited by coke, elsewhere iirc) snd the cold start cable pulled helped an engine which had been sitting for 6 years, fire right back up again.

Glad to hear all the work paid off with the sound of a running diesel.

I've spent the last couple of days cleaning up the wiring, battery connections, etc.

Part of the wiring harness on the '71 is a mess due to a "test harness" installed at the factory, whose purpose was originally to enable testing of various circuits, but whose usefulness has deteriorated over the last 39 years (with various connections being clipped by various owners over time). I think I've isolated a portion of the wiring that isn't useful/hooked up to anything, and will verify once its running that nothing is hot. If I can remove that, it will remove a lot of the wiring clutter near the radiator, which would be helpful.

Last night I started hooking up the glow plugs with two 10g wires going directly from the battery to relay, hooking up all but the LED, lights to the relay, then sending a single 8g (?) strand from the relay to the 50a wire fuse between the relay and the glow plugs. The relay is going to live in the engine compartment, just not sure where yet. I hope to "hot-rod" my glow plugs in the future (as has been described elsewhere) but its summertime and I'm more concerned about getting the vehicle on the road than top performance.

I'm still a little unclear on what wires are supposed to be going to the oil pressure sensor and the alternator, although I think I now have the oil idiot light wired in correctly (to the oil cooler, low-p sender). We'll see after I start up again.

Other than some items I still have to tidy up in the fuse box (tracking down wires installed years ago and fixing the headlight dimmer switch), I think most of the primary wiring has been taken care of. I just have to install the new wooden battery tray I built and waxed (as per Bob Hoover's Sermons), then I can install the radiator and get moving.

On Monday I ordered a Moab heater from a racing/hot-rodding company (who, it turns out, is fairly close by just over in Ohio). It's an aftermarket, self-contained heater that a lot of folks use for jeeps. In the next couple of days I'll be hooking that up in my heater loop, and replacing some of the temporary plastic hose fittings I had bought just to help keep the project moving a couple of days ago. (New fittings purchased from McMaster, along with some steel piping to run the coolant up front in).

I'll need the defroster for the bus to get inspected, which is why this is a priority, but I'm also hoping that I can use this for aux cooling in a pinch and/or to help tune my cooling system (i.e. see the efficacy adding heat removal to the heater loop). I'm a little concerned because while I was hooking up the glow plug wiring last night, I noticed that the coolant flange coming off the side of the head is slightly pinched. I knew it was going to be a tight fit, and even cut down the flange a little to provide additional clearance, but it seems tighter than I would have liked. I'm hoping that when I replace the hose connector there that I can re-route the hosing a little to alleviate some of the constriction. It looks possible.

Before I install the heater, however, I'm going to install the radiator and flush it with some prestone radiator flush, followed by a couple additional flushes with DI water. I read somewhere that flushing four times (with water, running at 5 minute intervals between draining) could remove an average of 88% of deposits, so that's what I'm shooting for. I also flushed it with a hose yesterday, in both directions.

The flushing process should be interesting in that I'll get to see how efficient the radiator is at cooling the engine at idle. I just have to figure out how to wire in the fan first. The red/black wire is power via a fusible link (presumably), and the two brown wires go to...ground? Both of them? Hmm...

One of the big problems in plumbing a TD into an old bus is just that: Plumbing!

Where to put the radiator and ensure adequate airflow, along with limiting failure points (having the fan run on high at 100% utilization is probably not optimal) is a tough engineering problem.

I've studied David Schwarze's process of putting a TD into his '73 [1], as well as an Argentinian's (?) take on where your rad should go[2], and they've both provided insights...and after some rough engineering calcs, I think I have a plan of attack. (I'll try to write up the calculations later.)

I believe that by utilizing the stock radiator in the engine compartment, I will be able to achieve the lion's share of my cooling, if only my cooling in traffic and/or at idle. I like this course of action for a number of reasons: (1) I like using stock components, (2) I don't like stuff under the bus - I like to go on dirt roads and that's a huge point of failure, and (3) the radiator is hidden from view. Putting the rad in engine compartment has its downsides, not the least of which being that: (a) its a tight fit, and (b) the ram-effect airflow at speed is inadequate at best. So I don't expect this to be sufficient cooling at load on the highway.

However, I've basically convinced myself that by using a small radiator under the bus and in the heater loop - something motorcycle sized - will give me enough additional cooling to make the system work. I like this idea because: (1) it is a small radiator which can fit between the frame rails and be protected, (2) I am already plumbing in the heater, and this will be close by, (3) with any luck the plumbing to the heater and aux rad will fit within the old air-cooled fresh-air heating ducts, protecting them from damage. The key here is making sure the coolant flow to this loop isn't overly restricted, either at the head outlet, or by the friction losses in the additional plumbing (distance and fittings). I may have to install a bosch booster pump somewhere in the loop, a consideration I'm not opposed to, but not something I'm jumping at. I'll probably attempt to get more ram effect and/or add more cooling area first.

Anyway, that's the plan. My goal for the cooling system (and bus) to perform such that:

1. Stock radiator fan runs in traffic and/or at idle, but only on occasion (not 100% duty...30% preferred).

2. Stock rad fan is not constantly on during cruising at 65 mph or so.

3. Temps when cruising in summer do not exceed 210F except possibly when pulling long grades and loaded down.

I think these are reasonable goals, with the exception of (2), which may be modified to "fan is only running at low" when cruising, to better match goal (3). Let's see what it takes me to get there.


[1] http://motorheads.net/vw/turbobus/
[2] http://translate.google.com/translate?h ... adiado.htm

Fitted the radiator last night. Boy did I forget how much space that took up. Now that its in place I'm starting to doubt locating it there as it doesn't leave much room to maneuver around. At the end of the day, I'm sure it will be fine though.

At present, however, I have the battery behind the radiator and I had to relocate the fuel filter (still not sure where its going) due to a clearance issue. This may be the thing that changes...I think I might end up relocating the battery to the left side (LIL) of the engine compartment where it's completely accessible, and put the fuel filter back on the right side. Not terribly concerned about it at the moment, but I'll have to buy some heavy gauge wire if I'm going to relocate that battery...

And........the radiator leaks. I sized the upper mounting bracket and just just have to drill holes, so that's good at least.

Checked the glow plugs and they get power with the key turned to the on position, although I'm having a problem getting a good connection for the glow-plug wire to the starter.

The engine compartment is still a mess with all the wiring and the rad installed. Cleaning that up will likely be what I tackle next.

i ran the engine for about 30 minutes total last night as part of the coolant flushing (and general testing) process:

Video is here: http://www.flickr.com/photos/avocado_tom/4824263966/

Ok. I've spent the last few days pulling the engine, cleaning things up, and generally house-keeping.

Once I had everything put together and had run the engine for a bit, I realized there was diesel fuel leaking from behind the firewall, probably from the 3/4" cloth fuel line/vent hose I had left in the return line as a junction where the polyurethane hose wouldn't fit over the connector. Doh!

So out came the engine, off came the firewall, and I removed the cloth line and extended the return line all the way to the center (upper) tank return, bypassing and removing the condensing loop from the top of the tank.

While the engine was out, I cleaned up all the wiring, wrapping it in wiring hose and ziptie'ing it. First time I've done this and not only was it easy, but it looks pretty decent. I also figured out the rest of the gauge wiring and hooked up the oil pressure light to the side of the head (upper) sender. Both idiot lights now come on, as expected. I also screwed the oil pressure gauge extender into the top of the oil filter so that I can put a pressure sender into it. Unfortunately, the VDO sender I have appears to be an M10x1.0 tapered thread (?) as opposed to a straight thread and doesn't easily screw in all the way to the extender. I'll figure that one out, but for now I just have the stock sender screwed into it.

While the firewall was out, I used my body work hammer and dolly to bang a big dent in it where the head flange water return is to remove some of the potential restriction there. I also mounted the glow-plug fuse and fuel filter bracket.

After doing all this, I re-installed the engine and...the fuel return line was now short! Doh! It almost reaches (I knew it was going to be tight) but not quite. I think I'm just going to install an in-line barbed fitting to extend it. I don't expect any problems from that.

I mounted the fuel filter and cut the fuel line there to length, then started working on getting the heater hooked up. I've had to do some alterations to the aftermarket Moab heater I got - basically cutting the box and moving the fan a few inches for better clearance - and now that that's almost done, I'm ready to fab some mount points for it.

After that...it's time to install the radiator!

I've been doing a lot of wiring rehab on the stock jetta TD wiring. The wires to the alternator plug were frayed and corroded, so I R&R'd them. The wires to the radiator: same.

So I've spent some time installing fuses, re-running wires, and generally re-habbing the stock connecting plugs. Hopefully this will avert electrical gremlins in the future and provide "years" of reliable service. At least these wires.

Sounds like you are paying attention to detail.

Fixing up all the bad electrical connections has to be done, but take some time to do right.

Seems like some pics would be nice in this thread. I would absolutly love to do a Tdi transplant into a nice Caravelle.