Modifications to a Detroit Speed Selecta Speed interval wiper system for a 65 Special

Dear V-8 Buick all-weather automobile enthusiasts,

Anyone who has driven a modern car in the rain knows how convenient it is to have interval wipers. If you would like to drive your classic on a regular basis, you are bound to encounter some rain and interval wipers are more than convenience - they are improved safety.

One possible to way to upgrade to interval wipers is to use the Detroit Speed Selecta Speed wiper kit:

http://www.detroitspeed.com/1964-1972-A-Body-products/121601-selecta-speed-wiper-kit.html

This kit replaces your Buick wiper motor and switch with parts from a more modern car. The crew at Orinda Motors suspect a Japanese model, perhaps a Nissan. So this route is not for originality freaks. The wiper motor most definitely doesn't look like your old Buick motor:


So if you want your engine bay looking original this is not for you. However many of us are willing to make some "modifications" to the engine bay, :3gears: so this may not be as great an issue. One other issue is that the Detroit Speed system has no provisions for controlling a windshield washer. On the 1964-65 Buicks, washer motor is built into the wiper motor. Also the activation switch is built into the wiper switch. So you would have to choose which functionality you want. Finally, Detroit Speed's proposed knobs and retaining nuts are to say the least functional and nothing else:



California weather is such that interval wipers is very desirable, so I went ahead and purchased the Selecta Speed kit for my 1965 Buick Special Wagon. I took one look at the dashboard knobs and knew I had to do better. This first posting will describe how I modified the Detroit Speed switch to make it possible to install it and operate it with the original Buick knob and escutcheon nut. As the rest of the system is installed, I'll add additional posting here describing any other modifications that were necessary to make the Selecta Speed kit work on my trusty wagon.

Disclaimer: these modifications will probably void your warranty and could fail. These tricks are offered in the usual as is. If they don't work for you, don't come crying to me - You've been warned!! ou:

Problem #1 is that the Detroit Speed switch is smaller in all dimensions. Therefore there it is too small to thread into the Buick dash. To solve this problem I purchased from a V-8 Buick board member a 1964-65 Buick 2-speed wiper switch. My plan was to sacrifice this part to make an adapter:



It turns out to be very easy to take apart the Buick switch. Simply break the crimp points shown on this picture:



Once you have the swich apart do keep the parts together as you'll need some of the internal components for the second modification. What you'll be left with is a housing that has a small retainer ring:



Removing that ring leaves you with a cylinder of metal that should be easy to thread to match the Selecta Speed switch. This is where I found myself about 3 months ago. The problem is that the thread on the Selecta Speed switch is an incredibly perverse 9mm - 7.5 thread pitch!! I searched high and low for such a tap. I went as far as to order from England a tap that I hoped would fit - no dice! Finally Greg at Orinda Motors proposed an All-American solution. After all, what is my poor wagon doing with metric threads anyway? He took a 3/8" 24 pitch die and rethreaded the Detroit Speed switch. He then used the corresponding tap to put threads into the body of the original Buick switch. A quick bit of cutting and the adapter was ready for use:



The plan is to black thread-lock to keep the adapter in place. All set - right? Unfortunately, it still wasn't going to work. Here is the original Buick switch in the dash:



I installed the Selecta Speed switch and this is what greeted me:



the shaft just wasn't long enough to mount the Buick knob. So it was time for modification #2.

First a quick comparison of the two switches. First, the Buick switch:



Now the Selecta Speed switch:



Also we need the dimensions of the knob that will finally get on this shaft:



The idea here is to splice the hex end of the donor Buick switch to the end of the Detroit Speed switch. So first you need to saw off the hex end of the donor switch:

Remember those other parts left over. You need to rescue the part with the hex end:



Break the shaft that supports the washer switch:



Now you can saw the end off easily:



That still leaves quite a connection challenge. I decided to get myself a piece of 9/32" aluminum tubing. Given my model railroad experience, I got it from K&S engineering:

http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXR814

I'm sure there are other sources for such material, but I was familiar with them. Here is the hex piece and the sleeve:



I then glued the hex end into the aluminum tubing using 15 minute epoxy:



I then glued this assembly into the Selecta Speed switch. Take care at this point because any glue that gets into the switch mechanism will kill it:



At this point I got a surprise. You need to remove a lot of the material to get the Buick knob to fit. Basically, you all but remove all of the aluminum tubing to get back the hex shape. I just did this by hand with a file and checked frequently to see how I was doing. Use the remaining bit of the Buick hex end as a guide to make sure you are continuing the same hexagon shape:



You also need to shorten the shaft to the same length as the original Buick shaft:



Once all this is done, this is what the Detroit Speed switch looks like when secured with the original Buick escutcheon nut:



The shaft is definitely a little beat-up by the filing process, but it is plenty strong and shouldn't have any problems handling the knob's torque because the force is applied across the enter length of the shaft thanks to the tight fit.

Here is the completed modification:



I noted a bit of wobble when I first put all this together. I assume it was due to some play in the adapter, but it might also be due to the knob not being a regular hexagon. It may be necessary to do a little additional filing and make the shaft match the knob to get the knob to turn perfectly straight.

With all the surprises and wrong turns, this modification look me literally months. However, I've been kind enough to make lots of the mistakes for you. ou: I would think someone could make this modification in a few hours of work. The only gotcha is the time needed for the epoxy to dry before starting to file away.

So if anyone is interested in having a Detroit Speed Selecta Speed wiper, yes you can keep your Buick knob, but it will take a little werk!! :grin:

Cheers, Edouard :beer

 

Re: Modifications to a Detroit Speed Selecta Speed interval wiper system for a 65 Spe

Edouard, do they offer a washer option?

 

No washer in kit. (Re: Detroit Speed Selecta Speed interval wiper system)

Hi Frank and fans of mid-60s V-8 Buicks

Alas, no they don't. There isn't any provision for a switch like the Buick 2-speed wipers at all, nor do they provide any hardware to power the washer. I understand that the Buick mid-60s two-speed wiper motor also includes the washer motor. So if you want to keep your washer you would need to provide another button and switch to some other sort of wiper motor.

I had thought about buying a generic washer kit and somehow back-fitting the generic motor into an OEM washer tank. You could then give yourself a button somewhere else and that would give you both interval wipers and a washer. However, I just don't use the washer feature on any of our other cars. Given the extra clutter in the engine bay, I decided not to bother at least for now. Perhaps it is a matter of location or type of driving, but I don't want to add things to my wagon that I don't personally use.

Oh well,

Cheers, Edouard :beer

 

Motor goes in per instructions. (Re: Detroit Speed Selecta Speed interval wiper)

Dear V-8 Buick tinkerers,

Just a quick update on the Detroit Speed Selecta Speed wiper installation on my trusty wagon. Greg has put in the wiper motor and harness and said it went in exactly as the instructions say it would. No tweaks needed:



The rest of the installation should be straightforward.

Cheers, Edouard :beer

 

Works great! (Re: Selecta Speed interval wiper system for a 65 Special)

Dear V-8 Buick all-weather automobile enthusiasts,

It has taken far longer than I expected, but I finally had a chance to test the Detroit Speed Selecta Speed interval wiper system. I needed to have some photos taken for collector car insurance and got caught in some unexpected drizzle. This is precisely the sort of situation that does happen frequently in northern California and is really a pain to deal with if you have older wipers. The Selecta Speed interval wiper worked as advertised. It isn't as convenient as a modern stalk-mounted wiper control, but because you don't need to change the intervals much, it is an acceptable procedure and looks perfectly original. It is an ideal solution to cope with those rare occasions when you are surprised by rain.

Even more interesting is that Detroit Speed has added a windshield washer option to this system:

http://www.detroitspeed.com/Electrical/121102-washer-pump-kit.html

It isn't clear if this system works with older versions of the Selecta Speed interval wiper system or not. Oddly, the interval wiper system itself is temporarily out of stock. However, what is especially interesting for older Buicks is that washer system is activated by a button in the center of the wiper knob (just like the factory 2-speed wipers on the 1964-5 A-bodies.)

Stay tuned, this may be a new product that is even mor' bettr' . . . .

Cheers, Edouard

 

Re: Modifications to a Detroit Speed Selecta Speed interval wiper system for a 65 Spe

I have the Detroit Speed wiper system for my 65 Skylark but have never put it in. One reason is the same as yours. The wiper knob. I will follow along with what you did. :TU: Thank you for blazing the trail.

 

Stay tuned! (Re: Modifications to a Detroit Speed interval wiper system for a 65)

Dear 1989GTA and V-8 Buick owners who can deal with da' wet!

Well you are welcome, but this is a case when this thread is - so - 2013 . . . . .

As noted at with my last post, Detroit Speed seems to be upgrading their interval wiper system to include controls for a washer.

http://www.v8buick.com/showthread.p...system-for-a-65-Special&p=2524930#post2524930

I still haven't had a chance to check into this, but if you can control the washer from the interval wiper switch that would work perfectly because it appears to mimic the way Buick had their 2-speed wiper and washer. All that would be needed is an original Buick 2-speed knob and I assume a similar modification so that the washer button can be threaded through the center of the rotary switch.

This project is back a few on my queue because I was supposed to upgrade the headlights on my trusty wagon back in . . . 2014 . . . . ou:

If you really are curious go ahead and give Detroit Speed a call. If you do please share with us what you learn!

Cheers, Edouard :beer

P.S. You would also need some of the washer parts, but they are out there if you look for them. If you need some pointers let me know.

 

Re: Modifications to a Detroit Speed Selecta Speed interval wiper system for a 65 Spe

I am not sure I want to do the window washer option. I did measure my Detroit Speed wiper switch and the thread on it is 3/8 x 32tpi. So I ordered a tap today. I happened to have another switch and I will take it apart like you did and thread the inside with the new tap and hopefully it will screw right onto the DSE wiper switch.

I am looking at my options to extend the 1/4" hex portion. I have a few ideas and I will share what I come up with. You can buy 1/4" hex stand-offs at the local hardware store. One idea is to drill and tap the DSE switch with an 8-32 thread. Same with the hex stand-off and use an 8-32 rod and screw them together. At the same time use plenty of Lock-Tite. The red for sure maybe the green.

 

Why didn't you talk me out of it! (Re: Detroit Speed interval wiper system)

Dear 1989GTA and V-8 Buick . . . . "second guessers" . . . . ou:

. . . So why didn't you talk me out of installing that washer tank? Sure I got a great deal on a washer tank from Fusick, but I don't know if I'll ever use the washer option either. I've been driving our 2000 Buick Century for 15 years and I still don't know how to activate the washer!! In the meantime, I really don't have enough space for the headlight relays!! . . . . . ou:

Be forewarned. I thought I new what the thread was on the Detroit Speed switch and in the end, Greg at Orinda Motors just "blasted it" with a new thread. The guys at Orinda Motors thought the wiper motor looked like a Nissan, so it may be a nasty metric of some sort. I tried to match that . . . and failed! :af:

Have a good time with the project! :TU: As you say, it might be better to just stick to the interval wipers and not make the project more complex than it has to be. Alas, I'm a glutton for punishment, so I'll probably try to get the washer scheme to work someday. Fortunately, someday could be - far, far away!! . . . . :laugh:

Cheers, Edouard :beer

 

Re: Modifications to a Detroit Speed Selecta Speed interval wiper system for a 65 Spe

I have the parts done so that the Detroit Speed windshield wiper switch will now fit in the original dash panel. Here are some pictures. Sorry about the quality of the pictures. I have a friend with a machine shop so I was able to take a different direction with the parts. We made up a bushing that has 3/8"-32TPI on the inside and 1/2"-28TPI threads on the outside. This was made out of 1/2" brass round stock. We put it in a mill and cut a flat on it so it will not turn in the panel.

As to the extension for the wiper knob to have something to grip to this is what we did. I happen to have a 6-32 hex coupler that is 1/4" across the flats which worked out perfect. We drilled into the end of the switch and tapped a 6-32 hole in it. We has a 6-32 set screw that was 1/2" long. We put that into the end of the switch and used red Locktite to hold it in place. About a 1/4" was sticking out. This was perfect for the hex coupler. With more red Locktite we screw the hex onto the 6/32 hex screw that was sticking out. Last with more red Locktite I installed the bushing adapter.

Here are some pictures.

The bushing


6/32" hole drilled and tapped into the end of the switch. Sorry about the picture.


Parts laid out in order of assembly


Assembled and compared to the original Buick one speed wiper switch.

 

Great job! (Re: Detroit Speed Selecta Speed interval wiper system)

Dear 1989GTA and V-8 Buick all-weather classic car lovers,

Great job! :TU:

Thanks for posting your solution - I like it! I had thought about your trick of treading a piece to extend the shaft, but I didn't have the tools to make that work. Your solution is clearly more sturdy and cleaner.

I'm waiting for Detroit Speed to explain how they add windshield washing to their system. If it looks reasonable, I might be starting this project over and looking to your scheme for inspiration!

Thanks again!

Cheers, Edouard :beer

 

Re: Great job! (Re: Detroit Speed Selecta Speed interval wiper system)

I think you did very good with the tools at your disposal. What we have done is give others solutions to the problem. Allen