Great Moments in Crappy Engine History: Volkswagen Wasserboxer [w/ Video]

Volkswagen Wasserboxer illustration

The German auto industry has earned a reputation for constructing vehicles of unmatched quality and precision. From the cheapest Volkswagen to the priciest Maybach, cars from the Fatherland generally feel rock solid and, when properly maintained, offer thousands of miles of headache-free service. Why do we use the qualifier “generally?” Well, just like not all French cars are weird and not all American cars are useless when the pavement gets squiggly, not every Auto out of Deutschland has been endowed with impeccable reliability.

Take, for example, the Volkswagen Type 2 T3, better known to inhabitants of this continent as the Vanagon. Like the two generations of VeeDub van (and pickup, we might add) that preceded it, the Vanagon was born with an air-cooled flat-four hanging out over the rear axle. That engine provided dependable (if not rapid) locomotion for the first couple years of the T3’s life (1979-1982). However, tighter emissions standards for 1983 onwards would prove too tight for the air-cooled engines, so the VW engineering staff set to work on a water-cooled replacement to take its place in the T3 (and only the T3; the company’s remaining air-cooled passenger cars would remain as such until their production runs ended). What they came up with was the Wasserboxer (Wasser being German for water). This is its story.

Volkswagen Vanagon brown and tan

Like its air-cooled predecessors, the Wasserboxer was offered in multiple displacements (initially 1.9L, later joined by a 2.1L variant) and featured two pushrod-actuated valves per cylinder. Another tradition the Wasserboxer kept alive was the lack of a timing chain or belt; the camshaft was gear-driven directly off the crankshaft. When cared for, none of this stuff caused any widespread issues. Venture into the cylinder bores, however, and you find the engine’s major Achilles heels.

Rather than placing conventional flat gaskets between the block and cylinder heads, VW engineers instead used rubber lip style gaskets to prevent leakage where the parts joined together. What’s more, the cast iron cylinder liners stuck out beyond the decks of the aluminum block; the protruding liners then slid into recesses in the heads, and the tops of the cylinders were then sealed off with compressible metal rings. The actual combustion chambers were bowls in the tops of the pistons instead of recesses in the cylinder head; these are known as Heron type combustion chambers. Finally, the casting around the cylinder liners was mostly empty space, creating a water jacket (or one big coolant passage) around them.

Volkswagen Wasserboxer installed view

If you said having combustion chambers essentially surrounded by water with multiple potential failure points sounds like a recipe for trouble, give yourself a cookie, because that was precisely the case. Not only could coolant leak out through breaches in the unorthodox head gaskets and cause overheating, but it could also slip past the compression rings and into the combustion chamber. This second, more disastrous scenario would cause anything from corrosion and misfires resulting from a little coolant leaking in to hydrolock, a phenomenon in which a non-compressible liquid (i.e. water) pushes back with tremendous force against its surroundings as it is given less and less space to occupy, when the cylinder is partially or fully flooded. The most common damage resulting from hydrolock is bent or broken connecting rods, though busted cranks, warped cylinder heads and cracked or holed blocks have also been known to occur in Wasserboxers. Early Wasserboxers were particularly susceptible to failed compression rings, as the use of coolant containing phosphate accelerated their corrosion. VW later filled engines with and recommended owners refill their engines with phosphate-free coolant, prolonging the rings’ lives significantly (though not completely doing away with the problem).

Other common causes of Wasserboxer death include poorly positioned sensors that didn’t let you know something was amiss until it was too late, and corrosion in the cooling system. Regardless of the cause, many of these T3-exclusive mills met untimely ends, leading to hundreds of irate customers and all sorts of warranty claim woes for Wolfsburg. Small wonder, then, that the vehicle that replaced the T3, the T4 (a.k.a. Eurovan) featured a far more conventional front-engine, front-drive layout and vertically-oriented inline engines. South Africa, however, would stay with the T3 until 2002, and from 1993 until then, it was equipped with VW and Audi inline-fours and inline-fives. The Wasserboxer would be VW’s first and last liquid-cooled pancake engine, and the last new horizontally-opposed engine it would introduce. The company’s last boxer engines (which were also its last air-cooled engines) were 1.6L units fitted to 200 special edition 2006 Brazilian T2 vans. (Water-cooled T2s are still being made in Brazil, some 45 years after VW’s second generation van was introduced!)

Volkswagen Vanagon silver

Maybe someday, VW will build another production vehicle powered by a boxer engine. With kissing cousin Porsche rumored to be developing a flat-four, it wouldn’t surprise us. We just hope they stick with what works instead of wandering too far off the reservation. That would work out better for everyone. 

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  1. Doctor

    Keep it air cooled baby! =) I’ve had air cooled 1980 Vanagon GL Westy since early release. We went everywhere together! For Spring Break the girlfriend & I covered over half America! In Maine we passed suburbans stuck in snow!
    To upgrade, I bought 1 Wasserboxer Vanagon GL Westy from the dealership.
    I paid cash for the camper. Before delivery the dealership asked for a week to add the extra purchased options to the Wasserboxer. Sure I said.
    Imagine my surprise when my dealer called to inform me that they blew the engine! VW wanted to know if they could refund my money?
    I bought another 1980 Vanagon GL Westy instead. Still Air Cooled & Luv-in’ it! =)

  2. Bc

    Rubbish, the wasserboxer gets a bad rap. I have a 1984 vanagon GL sunroof 97k on its original motor. I change the oil myself and replace and bleed the cooling system myself. I don’t let just anyone touch it, except my mechanic who replaced half the exhaust on it.

  3. Phil

    We had a VW camper 1970 with a 1500 single port air cooled engine, it was a POS, was virtually new when we bought it, got about 12mpg max and the performance was awful. Add to that that it needed three engines before it made 100,000 miles, due to the legendary valve heads falling off, because the valves were made in two pieces welded together!!! VW fitted a rev limiter in the distributor to try and prevent this problem, a spring loaded switch in the rotor arm turned of the spark when max revs was reached, which meant if you could ever get up enough speed to pass anything, you could almost garuntee the switch would eart out the ignition and cut the engine half way past the vehicle. the 1600 twin port engine was better, but fuel economy was still very bad. In reality, as a camper, the interion was quite spacious and comfortable, but it was truly awful to drive. It felt like trying to push a brick through water. My stepson recently bought a T3 caravelle camper mit der Wasserboxer, 29 years old, and still on its original engine. Incidentally, your description of the cylinder liners sticking out of the barrels, and fitting into the head to be sealed by a metal ring is almost identical to the air cooled engines.

  4. Mike

    I bought my 1984 vanagon in 1987, It has a watercooled engine (Wasserboxer) in it and now has 426,000 miles on it and has never been apart. I use it every day . I did have to remove the heads at 90,000 miles to replace the head studs that were eaten away because the original owner used prestone antifreeze in it. I also replaced the antifreeze.

    • Mark

      I have a 1984 Vanagon with over 300,000 miles on it and have been having an issue with it for several years which has not been resolved by several attempts to diagnose and repair the issue. The issue is that the Van runs fine some of the time and other times, although the Van does not “stall” (usually)… it will have a near complete power failure and cough and sputter and dip into very low RPMs for some unpredictable amount of time before it rallies and resumes apparent functionality. The Vanagon is in very good shape otherwise and I would like to sell it… (it belonged to my partner who passed away a year ago) but I have no idea how to price it, given this issue. Do I sell it as a Planter?

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