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O/D Relay Wiring

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Griz

Griz

Jedi Hopeful
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I keep finding discrepancies between the wiring diagram for the BJ7 and markings on the components I have purchased. This time it's the O/D Relay. Wiring diagram says terminals are supposed to be marked C1, C2, W1, and W2 while the new O/D Relay from Moss is actually marked C2, C3, W1, and W2. Left to right, terminals C3, C2, and W1 point up, and W2 is the lone terminal pointing down on the new relay from Moss. Last thing I want to do is fry something when I finally power up the electrical system on this car. Can one of you BJ7 guys tell me how your car's O/D Relay is wired? Thanks...Griz.
 
Griz said:
I keep finding discrepancies between the wiring diagram for the BJ7 and markings on the components I have purchased. This time it's the O/D Relay. Wiring diagram says terminals are supposed to be marked C1, C2, W1, and W2 while the new O/D Relay from Moss is actually marked C2, C3, W1, and W2. Left to right, terminals C3, C2, and W1 point up, and W2 is the lone terminal pointing down on the new relay from Moss. Last thing I want to do is fry something when I finally power up the electrical system on this car. Can one of you BJ7 guys tell me how your car's O/D Relay is wired? Thanks...Griz.
Click to expand...
I can't tell you how mine is wired since I installed a 5-speed conversion but I can tell you this....place a fuse in that circuit immediately!!! It's not a fused circuit and you'll fry the wiring trying to get your replay to work.
 
I had the same problem... Here is a photo of mine wired and working perfectly....

Any questions please ask..

Andrew

P1000583.jpg
 
Andrew, your relay looks completely different than mine, and I can't see any terminal markings on yours. I believe the early BJ8 is wired the same as the BJ7. Patrick, I have a note to myself to install a fuse in this circuit. Griz
 
Griz
I am no expert, but what I understand Moss sells two (2) different types of O/D Relay. One is a screw type which is used on the BN1through BJ7 and the other is a push type which is for the BJ8. It looks like the previous photo is of a push type which was only used on the BJ8.


I have a 61 MKII BT7 that someone along the way converted to the Push Type connector. I am sure they did this because of cost. The screw terminal (542-260) relay sells for about $180, compared to about $35 bucks for the push type terminal (542-170). I am in the process of converting mine back to the screw terminal despite the cost. Call me crazy.

The link below directs you to a great techical article on this subject.

https://www.healey6.com/Technical/Tech-OverdriveTroubleshooting.pdf

Good Luck

Jeff
 
Still doesn't help Andrew. My terminals are marked differently. I have a black wire, a white wire, a white/green tracer wire, and a white/purple tracer wire. I'm looking for someone who can tell me which wires to land on terminals C2, C3, W1, and W2. Griz.
 
Jeff, I'm trying to stay original in my BJ7 restoration so went with the more expensive relay. Thanks for the link. Did you notice that in one photo they have two terminals marked W2? I have my relay presently wired White, White/Green, White/Purple left to right across the top like in their photo, with the black on the bottom terminal. But again, their terminals are marked C1 and C2 while mine are marked C2 and C3. Griz
 
Grizz, look closely at the photo and you will see that the terminals are marked. I had the old style screw relay as well. Far right W1 is the the earth lead (doesn't come on a new wiring loom you have to make your own). W2 (far left bottom) is the white purple and above it is for the white. White green is for the middle terminal.
 
I have just finished rewiring my BJ7, the harness for the overdrive relay came with screw on connectors whilst the relay itself had push on terminals - I just drilled out the very small holes that existed on the push on terminals and bolted up the new connectors - job done.

:cheers:

Bob
 
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