Installing a BW35 automatic in a series III

[Paul A]

One of our Alpines is a Series IV Automatic. Once you get the Auto set up installed you won't be disappointed, they are a great drive, especially around town or in traffic. The only time we prefer the manual with overdrive is when you are on the motorway and travelling at top end speeds, then the auto revs high and feels like it could do with another gear.
Tim R

When I resurrected a Series IV with an automatic I mated it to a .030 over bored 1725 engine. I was very pleased with the performance with the bigger engine. That and being able to manually "shift" through the gears made driving it very much like a manual tranny car.

 

[Knightowl61]

Before getting ready to couple the engine & trans. The donor car had 45k miles and sat for the last 30 years so I drained the fluid and pulled the pan to inspect inside and replace the filters. WSM139 doesn't even mention filters (which I couldn't even find the pair I need), and doesn't say to change the fluid which the wsm says to use "Shell Donax T-6 only".


After a quick glance inside the tranny I think I'll just clean the filters and figgure the best replacement for the Shell Donax T-6 fluid.
I'm open to any suggestions or what to look for since I'm not familiar with automatic transmissions (except filter/fluid changes).
Also what is the best fluid to use - Dexron II or MERCON®V fully synthetic ATF or ???

 

[Tim R]

You need to use Ford Type F ATF fluid. If any dexron gets into the gearbox it will be ruined.

Tim R

 

[John W]

You need to use Ford Type F ATF fluid. If any dexron gets into the gearbox it will be ruined.

Tim R

Ford type F is all I've ever used. If you live in a neighborhood where golf carts are prevalent, an Alpine automatic is the "king daddy" of golf carts, and you're not limited to just the neighborhood. This thread has been enjoyable and refreshing to follow.

 

[DanR]

For you guys that don't know, John W has an Automatic golf cart (BW35 Alpine)....

I do too, except it no longer has the BW35.

 

[tony perrett]

We have a Series 4 GT with the BW35 gearbox - I don't know if it was ever confirmed how many automatic Alpines were made. They are not common here in UK and I think that most went to US.

 

[Tim R]

Tony, I've read numbers being claimed as being between 86 and over 4,000 automatics produced! Personally I think that there were probably a couple of hundred automatics made but I've got no evidence to prove it!

Tim R

 

[alpine_64]

Tony, I've read numbers being claimed as being between 86 and over 4,000 automatics produced! Personally I think that there were probably a couple of hundred automatics made but I've got no evidence to prove it!

Tim R

Definitely not as low as 86... Maybe for automatic ST alpines... The VAST majority of autos seemed to be GT cars...which makes sense.
Ive only seen 1 Auto ST in Australia and 2-3 on ebay USA.. All others being GT.

 

[Knightowl61]

Going to couple the automatic trans to the 1724 engine and found out the crank bushing is way smaller than the torque converter nipple.
Can't find any info for the needed bushing. WSM139 only says get a reconditioned engine -
Anyone know what size pilot bushing (spigot bush) I need? it will be a very thin wall.

 

[Knightowl61]

Found a solution for the bushing, 3/4" copper pipe has the same OD and slightly loose on the converter. A wrap or two of tape on the nipple should center everything.
Last possible problem (I hope) - I pulled the torque converter out to put in a new seal without paying attention to the depth position of the converter.
One article said to rotate the converter untill you feel 3 pops, then the converter flex plate should be 2 to 2 1/2 inches from the edge of the bell housing and can be pulled forward to attach to the flexplate. I couldn't detect 3 pops (or drops) and can only get .8" to the bell housing edge.
The WSM139 says to align the converter fingers and the front oil pump slots to 3 & 9 oclock positions. I can feel the converter sliding into the slots but still get .8" to the bellhousing edge.
Measuring the flex plate on the crankshaft to the engine measures .8" (no play tolerance) which doesn't seem right. Any ideas or tips?

 

[Dan Moore]

Are these trans hard to find I think I know where there is one
Dan

 

[Knightowl61]

All hooked up and working but fluid is leaking (seeping) through a new cork gasket at the bolt holes. I used a non-hardening sealer on the panside after pounding the holes more flat.
I'm wondering if the dip stick is correct and if I'm overfilling. Pictured is the dipstick (seated in the tube) and sticking out the bottom. The high (full) mark is almost an inch above the oilpan, don't know if it's right.

Any ideas? And should I coat one or both sides of the gasket with a sealer? If so what sealer is best?

 

[Tim R]

Here are a couple of photos of our Series IV Autobox when we had the pan off. I think that the level would also sit above the oil pan join. These are normally pretty oil tight provided the actual edge of the pan is straight. I THINK that Alpine Innovations might do a silicone gasket for the pan. They do others for various other Alpine leak prone areas. When you check the level you need to have had the engine running for at least 5 minutes, then turn it off give the fluid a little time to settle. Remove the dipstick, wipe it, then re-insert and take your reading.
Tim R

 

[Knightowl61]

Thanks Tim, great photos pretty much like mine. Makes me feel better.
Here's an interesting video of possible pan leaks.

 

[DanR]

Going to couple the automatic trans to the 1724 engine and found out the crank bushing is way smaller than the torque converter nipple.
Can't find any info for the needed bushing. WSM139 only says get a reconditioned engine - View attachment 26715
Anyone know what size pilot bushing (spigot bush) I need? it will be a very thin wall.

I have read this POST severaal times since it was first started. Very interesting project and am glad John started his project.

Just now a portion of this posting caught my eye....." THE WSM 139 only says to get a reconditioned engine. Does that mean a NEW one or perhaps a rebuilt one?

built to take the BW35.....MY early Series IV GT BW35 had an enhgine replacement sometime in its' early life, the reason I do not know. The engine was a factory replacement and does not have the serial number on the block as was done by Rootes when replacing the engine.

With that information comes the question (?) Why? To save changing over the driving plate and Spigot bush.

I must now take a look at my "REPLACEMENT ENGINE", JUST TO SEE WHAT DIFFERENCE there is between the two SIV engines I have.

 

[Knightowl61]

I don't think there is any difference in engines, I ignored the WSM and bolted the drive plate to a spare 1725 engine. The Spigot bush is larger than the torque converter nipple but I don't think it even goes in the bushing. The 4 special bolts connect the drive plate to the converter so there are no moving parts there anyway. All seems to work except a pesky oil pan drip now.