Start me up..

Brief update today. The weather is finally getting nice after a dreary morning, so I want to get out into it. I finally have some traction on the starter effort, so today's post will cover that.

Background
The 1972 VW Bus ran a 002 transaxle. This is the transaxle (transmission + differential) that appeared on the bay window bus through 1975. After 1975, they switched the bellhousing (and a bunch of other things) and those transaxles are known as a 091. Once production was stopped on the bay window bus, and the vanagon was produced, the transaxle was switched to a side-shift and the number was changed to 091/1. The bellhousing, though, wasn't meaningfully changed for the starter.

Westyventures.com started fabricating an adapter to allow a starter from a manual tranny TDI to bolt up to a 091 (or 091/1) transaxle a couple of years ago. This was great news for the wider TDI conversion community. What about the auto-transmission folks? Well, about 6 months ago, westyventures (Karl) stsrted fabricating an adapter for the auto-tranny as well. Much rejoicing for the vanagon folks.

The challenge
The 091 and the 091/1 bellhousings required a starter that projected about 1/4" less deep into the bellhousing as the 002 starter. This is why the 091 starter and the 002 starter are not interchangable. The 002 starter would overshoot the flywheel by 1/4". When someone wants to swap bellhousings between these transaxles, that 1/4" affects both the output shaft and the starter. Since the vanagon and the late bay have the same starter requirement, and most TDI conversions are vanagons, most off-the-shelf adapters don't fit the early bay.

The discovery
I got the specifics from Karl (westyventures.com) for his adapters. After running some math and threading with Karl about his products, we made a discovery. The requirement for starter alignment in an auto-tranny vanagon is almost exactly the same as the requirement in an early (002) bay window manual tranny. That 1/4" was accounted for with the auto-tranny adapter. I ordered one, and I'll be test fitting tomorrow.

My numbers
TDI-
short: 1.5625
long: 2.25

002-
short: 0.8125
long: 1.25

auto adapter: 0.83 ->
short: 1.5625 - .83 = 0.7325
long: 2.25 - .83 = 1.32

overhang:
short: 0.08
long: 0.07

short = distance from bolt plate to near edge of sprocket
long = distance from bolt plate to far edge of sprocket

pictures:
top: TDI manual starter on the left, 002 starter on the right. Note the difference between the 2 starters in terms of depth from bolt surface to sprocket.

middle: TDI starter with a westyventures auto adapter.

bottom: TDI starter on the left (with adapter), 002 starter on the right. See how the sprockets are almost exactly aligned now.