Overdrive Wiring ect.

[Alpine James]

Hi all,

Some time ago I replaced the defective transmission on my SV with an overdrive unit I purchased along with an entirely disassembled car. Being as I am in rewiring mode I thought I would consider getting the OD unit operational. When I purchased the vehicle I asked the PO if the OD unit was functional in the car before being scrapped since the original car was a non OD vehicle. He assured me that it was working at the time of its final journey. However, since the car was disassembled when I purchased it I am unsure if the transmission was properly installed using the original switch and relay or something was cobbled together. I did check the solenoid before installing the transmission and it appears to be functional.

My first question is: What am I looking for as far as parts? I have a bag of column switches but most I believe are turn signal/horn switches. I also have a box of assorted electrical parts, dash toggles ect. and a few items of unknown purpose and origin.

Working on the assumption that I do not have the stock parts, and my understanding that replacements are no longer available, is there a practical work-around that will achieve the purpose?

Thanks, James

 

[Tom H]

James. I have written up a way to wire an OD better than original. I think it's linked here somewhere and I will find it or repost it. Bit two things first:

1) You say the solenoid "appears functional". How did you test it? Two things you need to verify- Does it pull in when you apply 12 V? and Does the current drop down after it pulls in?

2) Do you have WSM 145 ? It shows everything about the OD wiring. \\

The OD switch mounts in the oval hole opposite where the Turn signal switch exits the steering wheel cover, actually mounted in the oval piece that fits in that oval hole. You alos need the relay that looks like the metal can relay that is part of the alternator regulator system, except it has more terminals. But my method allow you to use a more common relay.

Tom

 

[Tom H]

Here's a link to my post that describes how to use a more common relay for the OD relay. See post #8 in the thread.

http://forum.sunbeamalpine.org/index.php?threads/overdrive-relay-siii-sv.17211/

Do you have the OD wiring harness? That would save a lot of work.

Tom

 

[Alpine 1789]

Do you have an OD switch? The SV switch is a momentary contact on-off-on switch that matches the turn signal switch. They are hard to find, but do come up on eBay fairly regularly. As a temporary replacement, I would think something like this would work fine - https://www.amazon.com/Morris-70280...8&qid=1518199083&sr=1-1&keywords=morris+70280 - but trust that our resident electrical engineers will correct me if I am wrong.

(Edited to correct original recommendation.)

 

[Alpine James]

Hi all,

Thanks for the feedback. It all seems quite straight forward but I do have one question.

Tom, your modified drawing shows a 4 terminal relay with the added diode and resistor, but from I find, the 6RA is a 5 terminal relay as per WSM 145.

Thanks, James

 

[Tom H]

James, Yes the stock arrangement uses a 5 terminal relay. It's a special type of 6RA relay. It has a second set of contacts that are used to maintain power to hold (or "latch") the relay closed, and maintain power to the OD solenoid even after you release the column switch from its momentary ON position. If you have such a relay in the set of parts you have then you can use it and wire it as per the original drawing in the WSM. But those relays are hard to come by and are prone to fail. So I designed a method to accomplish the same operation using a more common 4 terminal relay by adding a diode and a resistor. You can use a fairly common Lucas 6RA relay (with 4 terminals) and maintain a "near original" look. or you can use an even more common square, plastic housing, relay found at any auto parts store. Note that many of the common relays found at auto parts stores also have 5 terminals, but that 5th terminal is not the same as the 5th terminal on the special Lucas OD Relay and those 5 terminal relays can also be used (with the added diode and resistor) by simply not using that terminal.

To clarify about a 6RA relay, understand that the term 6RA is somewhat a "generic" description. If you look at the description of the SV alternator control circuit in WSM145 you'll see a different 6RA relay with just 4 terminals. That's the more common type 6RA, and they are fairly easy to obtain.

Tom

 

[Ashfried]

Here are some photos of the overdrive relay and switch (minus the stalk).

 

[Tom H]

Ash, that should help! And note that the number stamped on the "special" 6RA relay is almost surely 33199. I cannot read it from the photo, but every one of these OD relays that I have seen has that number stamped on it.

 

[Alpine James]

OK, So what I found was this, which would seem to be the correct part but without seeing a schematic......

https://www.bpnorthwest.com/relay-6ra-type-lucas-brand.html

Is it possible that the once hard to find part is now being manufactured again?

 

[alpine_64]

OK, So what I found was this, which would seem to be the correct part but without seeing a schematic......

https://www.bpnorthwest.com/relay-6ra-type-lucas-brand.html

Is it possible that the once hard to find part is now being manufactured again?

Nope... Thet have been making 6ra for ages.. But its the sepcific self latching relay that the series 3-v uses.

The early cars have a more simple 6ra. This new one doest have enough terminals

 

[Tom H]

James, No, this is not the same. You can click on the second image below the picture and see this:
https://www.bpnorthwest.com/catalog/product/gallery/id/2447/image/9659/

That view shows the schematic of the relay and you can see it does not have the double contacts but simply a double connection to the single contact. Also in the "Product Description" at the bottom it does not list P/N 33199 as one of the parts it replaces.

I take it from your search that the parts you have do not include the original 33199 relay.
Do you have the original column switch? '
Do you have any 6RA relay?
Why not just use my diode and resistor mod to use a common 6RA type?
Mike Harman has published my more complete write up on the mod here:

http://mhartman.net/files/sunbeam/Overdrive Relay Replacement V1-0.pdf

Also there is a guy in the UK, I think who supplies a 6RA relay in which he has already installed the diode and resistor.

Tom

 

[Alpine James]

OK, I did see that diagram after I posted. So I will go ahead with Tom's solution.

I don't have any sort of relay or the column switch so I was goin to use the switch previously mentioned by Jim and a new modified relay. I am hoping that I can source both those parts locally along with the diode and resistor.

Regarding the OD warning lamp, where would one locate this?

Thanks, James

 

[alpine_64]

.

Regarding the OD warning lamp, where would one locate this?

Thanks, James

Top left of dash. Should be a blanking plug there. Same alignment as the indicator warning lamp

 

[Tom H]

A typical SV dash will not have a blanking plug where the OD lamp would go. The dashes were molded with that hole blanked. But if you drill a hole at the upper left of the tach, pretty evenly spaced between the upper right of the ammeter and the upper left of the tach, you'll be just about the correct location. The original OD indicator was an amber light, but I used a faded red Ignition indicator and it looks fine. Some have taken added color to come close to original.

Finding the resistor locally might be difficult. Order everything (except the relay) from DigiKey. They are very easy to deal with and charge minimal shipping.

 

[hartmandm]

Here's the new OD relay option Tom mentioned: http://alpineinnovations.co.uk/products/overdrive-relays-solenoids-etc/

If you want to modify a relay yourself, another option to check for buying discrete parts like resistors and diodes is Mouser Electronics. I've sourced multiple small batches of parts (including quantity 1 of things). Pretty quick to ship. Cheap shipping.

The Lucas SRB111 relay is a good starting point. It looks similar to the original relay. See page 7 of my OD write-up for what the relay looks like modified: http://mhartman.net/files/sunbeam/OD gearbox installation.pdf

See page 21 in the OD write-up for where I mounted the OD warning light in the dash. I had a spare series IV dash with the OD warning light hole blank to use to determine the proper location.

Mike

 

[alpine_64]

A typical SV dash will not have a blanking plug where the OD lamp would go. The dashes were molded with that hole blanked. .

Hi Tom... My bad.. Was thinking of the wood dash where they use the small blanking plug on s3-v and tiger.

Forgot the vynil dash ST cars didnt do that.

 

[hartmandm]

Hi Tom... My bad.. Was thinking of the wood dash where they use the small blanking plug on s3-v and tiger.

Forgot the vynil dash ST cars didnt do that.

The blanking hole is present on the series IV plastic dash I have. It was dropped from the Series V dashes.

Mike

 

[alpine_64]

The blanking hole is present on the series IV plastic dash I have. It was dropped from the Series V dashes.

Mike

Mike,

Can you confirm something for me if you have a siv snd sv dash.

I know a s3 had a blanking plate. Apparently maybe a siv too. Iirc the back of a sv dash may have a raised round area (very slight) where the od light would go.

If you have access to check that would be great.

 

[hartmandm]

I already drilled my SV dash from the front side while it was mounted in the car. I think it is too late to check what the backside looked like! Hopefully, someone else can check an unmolested SV plastic dash.

Mike

 

[Tom H]

I have a spare SV dash. You can see a mold mark on the back side where the OD lamp would go, but it is just a slight outline where they plugged the mold. My guess is that the plug was removable so they could mold dashes with the hole, but I think they stopped putting the indicator in even when the OD was installed. Note that the WSM 145 schematic for the OD circuit does not show an indicator. But I think the OD harnesses all included a wire for the indicator.