Anybody fitted a JK hot start relay? Help please.

[KevH]

I bought a hot start relay from Just Kampers ages ago and have never got around to fitting it. Now is the time.

Yes, I know, there are loads of previous postings on this topic, but the trouble is this, that the instructions on JK's site (nothing came with it) are totally different to what everybody else describes in other threads. :roll:

For example JK say:
- take the wire from the starter switch off terminal 50 on the solenoid and attach it instead to terminal 86 on the relay. Everywhere else states it goes to terminal 85.
- run a wire from tereminal 85 on the relay to earth. Elsewhere the wisdom is to run to earth from terminal 86.
- wire terminal 30 on the relay to terminal 50 on the solenoid. Again, this is at odds with other instructions which state that terminal 30 on both relay and solenoid are wired together, suitably fused.
- finally wire terminal 87 on the relay to the battery. Elsewhere the guidance is to wire terminal 87 to terminal 50 on the solenoid.

What the heck is going on here?

Has anybody fitted a JK relay and, if so, which instructions did you follow and what was the result?

Very grateful for your help with this, as I don't want to be wiring the starter up incorrectly whilst lying under the bus. :lol:

Kev

 

[Peter Good]

Hi Kev,
Confusing isn't it!
In actual fact, if the JK relay is used in isolation (i.e. not as part of a bank of relays for other purposes) then it doesn't matter if the 85 and 86 are interchanged, and the same applies to the 87 and 30.
However, to be absolutely correct here are definitive connections: -
85 Earth
86 Terminal 50 lead connection
87 Terminal 50 on the starter solenoid
30 Battery +ve via fuse
Some relays have a diode between the 85 and 86 terminals and in those situations it most certainly does matter that the correct terminals are used. The JK relay doesn't have a diode inside.
Peter Good

 

[KevH]

Thanks Peter.

So, 85 and 86 are interchangeable when using the JK relay...that makes sense given your explanation about the workings of the JK relay. I'll stick with 86 to earth as per the type2.com/bartnik site, and I'll ignore the JK instruction.

And thanks for confirming that 30 is definitely live; that is the issue that really spooked me. I had this image of being run over by my own bus

Kev