VW diesel into T4?

[Jooseppi Luna]

I had a great idea this week I was thinking to myself about how much fun it would be to own a small VW Rabbit diesel from the '80s and how much fun it would be to own a T4, and then it came to me: a VW 1.6 diesel in a T4! I mulled it over in my head for a few days, Googled it, and found CRT's thread. There is nothing new under the sun :->. I saw that he gave up on fitting in a VW engine due to clutch fitment concerns. After milling it around in my head a little more, I remembered a thread from a site called superturbodiesel.com in which a guy was modifying a late-eighties Mercedes five-speed to fit his early-eighties 240D (that only came with a four-speed in the US). One of the things he did was modify the input shaft as quoted below:

6- Modify the input shafts (if you decide on this route) In order to do this, you will need to measure the length of the 240 shaft over the 190 and make sure that this is maintained during the swap. You will need to cut the end off of the 240 and weld it onto the 190. Both shafts are hardened on the outside only. A comparison shot-
notice the general large difference between the two. I chose to make my length measurements off the end of the taper on the bearing side of the shafts-

After cutting the shafts-

The machine shop cut the shafts, drilled down the center point and threaded the 190 bearing side and the 240 spline side. pic-

I had the shaft checked for balanced after cutting, and a 45 cut into it for better weld penetration.
before and after welding-


7- Check the input shaft for true. After the welding its worth taking it back and having it cut down and rechecked for true and balance by the machinist. Again, there is no better time than while you have it apart.

He since put 10,000+ miles on the setup.

Could this be done with VW and T4 input shafts? It seems like a good solution, as it would allow use of the VW clutch with the T4 tranny. Even if you had to build an adapter plate and custom motor mount arms, I don't think life would get too terribly difficult -- and then you'd have a diesel for which you can readily find parts in the US, which I think would more than save money in the end. The VW NA 1.6 diesel makes ~55 HP and ~75 lb ft of torque, so I don't think one would have to worry about ripping the input shaft up.

I recently became aware of a summer-winter swap program in MA where you can swap registration between different vehicles for $25 per swap (with the idea being that someone with, say, a sports car and a Jeep could drive the cars with one registration, using the appropriate car for the appropriate season. Since this would make adding a third car to my fleet quite affordable, I was thinking of buying a T4 and trying this out. What do you guys think?

[Petros]

Although the VW diesel is a common engine I see several problems with it. It is not terribly reliable, they need regular major internal engine repairs and the parts are quite costly. Also, since it is a common small diesel, it is very desirable engine for putting in boats and use as stationary power plants,as well as other cars, so even used ones that are beat are very costly. I mess around over on the boatdesign.net and there one guy that had one of these VW small diesels in his fishing boat, it started oil mixing with the coolant, took the head off and the gasket was okay, found a crack in the head. replacement used head was $600, so he risked having it welded by a guy who has done these kind of repairs on VW diesels routinely. The fact that is is a common problem is rather troubling to me. I would look for something else.

Despite the the promise of what a high fuel economy and low maintenance small diesel can possibly deliver, diesel fuel prices have been climbing faster than gasoline, the modern emissions controlled diesels are not reliable (like any EFI, too many sensors and a very complex system), parts are costly and hard to find. Add on top of that the cost of the conversion, plus the risk of any of the home made parts (like that input shaft) might fail, I do not think I would do it. It would take many decades of use to break even, if that point should ever occur considering you might be spending money on it regularly to keep it running.

I have owned several diesel powered cars and trucks, although their economy is remarkably good, over all their extra operating costs and hassles makes it hard for me to consider owning another one. The exhaust is also stinky and sooty (the newer ones are not as bad), and in very cold weather starting and warm up are very troublesome.

if there was a more reliable engine that was bolt-in, I might consider it, but I do not think the extra cost and trouble of getting a different engine to work in Tercel could make it worth while.

[dlb]

i think it's a really neat idea jooseppi, and likely one that quite a few others would also be keen on, but after my experiences with VW's i agree with petros. i have found them to be temperamental, require rebuilds way too often, and their parts are overpriced like crazy. it might work out well for you but i personally don't want to work on another VW thing again.

[Jooseppi Luna]

The specific VW diesel engine that I am interested in is the 1.6L NA made in the '80s and early '90s. My understanding is that it id supposed to be the most reliable of the VW diesels. I don't know which of many VW diesels that guy withthe boat had, but if it had EFI, it most definitely was not the 1.6. Being an old engine, it doesn't have things such as common-rail injection or even any computerized fuel controls to mess with. Part of my interest with this project is the potential of rebuilding the VW engine -- I ran up the tab for rebuilding one them using quality (in most cases OEM-manufacturer) parts and the total was $390 less shipping... of course I would also need some machine work, but that shouldn't add more than $100-$200. This engine would not be EFI and probably wouldn't have any emissions controls besides an EGR and perhaps a trap ox... and those have a habit of getting lost in the shuffle ;->.

I'm working on designing a centrifuge that will allow me to refine used motor oil so that I can run something along the lines of a 75% oil/25% RUG in my Mercedes, so currently one gallon of fuel would cost me $0.90, which would help offset the cost a little bit, although I realize that that would still take a while and that I may outlay more $$$ for this than planned -- that would be OK, as I've learned not to walk into a car project assuming that I will make some sort of profit.

I already own a diesel, so I am aware of the qualities of the exhaust -- however, a good diesel in tip-top tune with a purged engine, redone injectors, adjusted valves, etc. should smoke little to none. Of course, it is a different car and so not applicable, but my Mercedes starts the best of all our cars and the PO started it down to -6*F without problems and without a block heater. The VW probably wouldn't be as excellent, but it's not the only car either... and we generally stay around 15*-20* and above.

I can understand the reservations about VW in general, but I'm thinking that using this one specific engine would berelatively safe -- especially if I rebuild it.

dlb -- you owned a thing? I've only seen one, but they look neat.

[Jooseppi Luna]

Oh -- and another engine option would be the Mercedes OM601 engine, a NA 2.2L 4-cylinder diesel that makes 72 HP and 96 lb-ft of torque. It has a very good reputation and was available stateside in the '80 in the 190D 2.2.

[Mark]

I've also fantasized about installing an older diesel in mine as well if the gas engine ever quits. It would probably be more of an experiment than practical, eg. trying different fuels, 50/50 diesel-vegetable oil, etc. Realistically, I don't think it would be economical in the long run. There's also my other fantasy about converting to electric....

[Petros]

the mercedes engine would be a much better choice. I have owned a 240D, which I think is a similar engine with more displacment. It is mechancially very reliable, although some of the external system are kind of kooky ("German engineering" is a crock). the glow plug circuit sucked and the cooling system was WAY more complicated than necessary (both would be easy to redesign in a swap). It is a big heavy engine, but it is reliable (used in farm tractors, taxies and deleivery trucks all over Europe). As long as you can get parts it would be a much better choice.

It is still a lot of effort to get the engine to mate up with the Tercel4wd trans. You take a car that would be worth perhaps $3000, and put perhaps $2000 worth of parts and effort into it, and end up with a car worth what? maybe $3000 at best, if you do not scare anyone off with such a strange installation. If you could do it with all toyota parts, you would not likely scare as many people off if you had to resell it.

Not that you are planning to sell it ever, but your needs and interest change as your life changes, so not likely you would keep it for the rest of your life, even if you could still get parts for it 20 years from now.

[dlb]

dlb -- you owned a thing? I've only seen one, but they look neat.

haha sorry, i was referring to the vw westfalia camper van we owned and not actualy a VW thing. should have chosen my words more carefully.

[Petros]

I was around when the "Thing" were being imported, everyone thought they kind of jeep-like Thing, and perhaps useful like a jeep. not so, it was just a regular bug with a different body. kind of "decoy" off road vehicle. the novelty wore off since it was less useful than a regular bug, and not as "cute" as the bug.

[splatterdog]

Radical swaps have never enthused me. For almost every obstacle there are usually ten more right after it. Those ten each have ten,etc...

I believe cathoderaytube is still working on his diesel swap. I'm surprised he hasn't chimed in. Pretty sure he was thinking vw, but went with a toy diesel instead.

If I was doing something this radical, I would just go RWD. But then it wouldn't be diesel either. I've daydreamed about a supercharged 3800 freakwagon! Rubber at 75, OK! Plus I'll take rubber smoke over diesel anyday.

[larry mcgrath]

I think you should go for it, I just got back from fly fishing 225 miles , ran 75-85 mph all the way in the (Rocket) 32.4 mpg ,everyone here said the trany would'nt hold up to 165 hp. guess what it does. Dont let the nay sayers stomp on your dream, go for it. Larry.

[Jooseppi Luna]

Hey Petros, I remember you mentioning your 240D before :->.  You will be happy to know that Mercedes redid their glow plug wiring setup in 1980 from wiring them in series to wiring them individually.  

The 240D actually would have had the OM616 engine, which was part of the OM61X engine family that was manufactured from 1968 to 1985.  The OM601 is the smallest member of the OM60X engine family, which debuted in 1985 and ran until ~2000.  The OM60X family was a revolutionary leap ahead from the OM61X family -- quieter, more efficient, more powerful, more maintenance-free (no more valves every 15k).  I'm very familiar with the OM61X family and somewhat familiar with the OM60X. 

The OM61X family used an iron head where the OM60Xes all use aluminum heads, and so the OM601 weighs a bunch less than the OM616.  The one educated guess I can find on the OM601's weight is 350 lbs.  Also, the valves are mechanical in the OM616 but hydraulic in the OM601.  The OM601 doesn't really have any major known trouble spots that I'm aware of.  I believe someone on PeachParts (the Mercedes forum I'm on) bought a 190D 2.2 with over 500k on the original engine/transmission.

On the VW engine topic, I started a thread on PeachParts and learned a bunch.  Only one guy mentioned head gasket or head issues.  The valves were adjustable up to 1985; 1986-on were self-adjusting.  The head bolt heads were enlarged in 1985.  The one major known issue is that apparently the AC and alternator bracket for the Mk2 Jetta has a tensioner that likes to eat belts.  Some are just fine and some chew up belts every few months.  However, they do seem to be durable.  One guy had 436k on his when it was totaled :-<.  The NAs made 53 HP and the non-ECOdiesel turbos made high 60s HP. I thnk the corresponding torque figures are 72 lb/ft and high 90s lb/ft.

[Jooseppi Luna]

Woah, someone on PeachParts offered to trade me a 1986 diesel Jetta for my spare OM617 turbo engine. Stay tuned...

Just noticed that this was post #50 for me and that I am now an advanced member. Everyone watch out as I wield my newfound power...

EDIT: The car would be an '86 with an '85 NA engine. He's put tons of work into the car including having rust welded up, so I'd probably be flipping this if I do get it. It would certainly give me a feel for whether or not I'd want the turbo instead...

[splatterdog]

80's vw diesel? Wow. Last one I experienced, at idle and parked, the dash was bouncing like driving over washboard. Better add a lot of dynamat.

Consider me more of a realist than naysayer. I know, if you don't have something nice to say... But, I've never done(or seen) a diesel swap. Seen lots of swaps. To gas that is. Many domestic 80's diesels got converted. All were bolt in deals. Over the years, I've also have had to convince lots of people that alternators, water pumps, tires and other essentials are a good idea. Elective surgery such as this conversion is way out of most peoples grasp, in ability and/or finances. Finding a machinist will be the easy part. Finding an auto shop to touch it before,during,after will take a miracle, unless you bring a blank check. Many would turn it away completely stock, just because of it's age.

Sorry if I come across as a glass half emtpy kind of guy. Being inundated with broken cars, some with broken owners, for half my life does take a toll!

My most radical coversion, a mazda engine in a mazda. The owner was waayy over his head. It was a 3 rotor in a rx. After over 150 hours it was time to finally add coolant and soon attempt start. Too bad the owner had leak tested the engine with straight water and didn't fully drain it. A middle segment had a ruptured water jacket a couple inches away from the drain plug that was't utilized. Nothing like starting over after all that time and money. Working on it for months between regular cars sucked too. Was frequently waiting for parts or money. And he thought it was close to running when he handed it off to the shop. A better project at this same shop was stuffing a 502 crate engine in to 81 cutlass. It was a total beater at the beginning with a 3.8 v6. I started after the initial build(built the exhaust system though), but got to add a supercharger and nitrous to it. The one nice thing on projects is a client that doesn't ask how much, just when will it be done..

Good luck!

[CathodeRayTube]

My Diesel T4 project is still slowly progressing, and will never be abandoned...i have been busy with many things lately so it has been dormant for a while, however in the last several months i made much progress. In a nutshell, Im using the 1N-T toyota Turbodiesel ordered from Japan, which is essentially the toyota counterpart to the VW 1.5/1.6...It is 1.4L, Indirect injection, all-mechanical, and was purchased for $1600. It was originally in a 90s JDM Tercel. I gave up on the VW plan a while ago (but not the whole project) because it was so much easier to stick with toyota parts and order the toyota engine. The 1N-T will bolt up to the T4s tranny with no adapter, and only minimal modification to the flywheel (diesel bolt pattern drilled in stock 3A flywheel), and a modified oil pan to clear the front differential case and steering hardware. I am currently actively working on the custom oil pan, and hope to have it running on a stand soon. Stock starter also bolts to the whole thing fine.

Custom engine mounts will also be in order, but thats relatively simple also. The 1N-T is also actually smaller/shorter than the 3A, so i have plenty of space for everything. I have verified that everything will fit together with the simple mods above, its just a matter of time/motivation and weather (no, not even money), until i have the car running & driving with the new engine.