How To Do the Bosch Relay Mod???

[Trevor]

Originally Posted by kwren

I know 2 wrongs don't make a right, but neither does one wrong make a right!

Actually that statement is meaningless, like some of the attempts that to prove that everyone else is wrong on this subject. We should all be able to learn from each other and if some can't, I think that tells a world about the person that is unable to.

When you come on demanding proof and can never provide proof for whatever your contention is, you need to do some real deep soul searching.

Now... Tell me that I am wrong about this!

Keith

Keith, please keep your cool.

I always can always prove if need be, statements which I make. Where can you show otherwise. Furthermore any mistake I have made has been followed by a sincere apology

Incidentally, the Bosch relay comes new in a little box that actually does not have a ground anywhere on the box or the relay that is in the box. Anyone that says the Bosch relay is always grounded is... WRONG!

The relay has a connection point which is capable of being grounded. I may have stated that the relay is always grounded, within the context of the post. So what?

No electrical component has a ground as such. Ground is better described as "earth", which is the term used by exact engineers. There is only one place where this can be found and that is not in a little box.

[Trevor]

Originally Posted by kwren

This question is to help me learn how low voltage can cause excessive current in the starter circuit. not the starter motor itself.

I will wait right here for your explanation, and no proof is required! Seeing what you come up with will be reward enough!

Keith

If a circuit conducts excessive current, the same current will flow within all of the components within that circuit. Circuit, circle, i.e. unbroken path of a conductor, or any stuff for that matter. The starter motor forms part of the complete circuit. There is no way it can side step.

If you can show otherwise, you most certainly will be able to claim an reward, much to the disgust of the late Mr. Ohm.

[kwren]

Originally Posted by Trevor

If a circuit conducts excessive current, the same current will flow within all of the components within that circuit. Circuit, circle, i.e. unbroken path of a conductor, or any stuff for that matter. The starter motor forms part of the complete circuit. There is no way it can side step.

If you can show otherwise, you most certainly will be able to claim an reward, much to the disgust of the late Mr. Ohm.

I = ExR Mr Ohm. lower the voltage the current doesn't increase... it decreases.

Keith

[kwren]

OK Trevor, What is my reward?? (Hope it is money)

Keith

[Trevor]

Originally Posted by kwren

I = ExR Mr Ohm. lower the voltage the current doesn't increase... it decreases.

Keith

Mr Ohm just told me that he only said that, provided his resistance is not messed with. Mess with his misses amperes, and he will resist your current resisting. His mate Mr. Watt, wants to know, what's what in a your circular circuit? Mr D. Bees is simply comparing things with Mr. Henry. Mr. Lumens is out.

[Elaine]

Australia vs. New Zealand... it's always interesting...

Let me bring my Canadian perspective to this. To me the main purpose of this forum is to provide SVX owners the opportunity to learn. By reading all these posts I learned that the main reason for my SVX starting problem is the key contact and nothing else (thanks Trevor!). I also learned how to fix it (thanks oab_au).
Without being mean I encourage some people here to be more receptive to these facts:
1. At a given voltage a lower resistance will draw a higher current. (Ohm's law).
2. Ground and Earth are two different things. Depending on the application they may be connected together but it's not a must.
3. There is no generic relay (including most of the auto ones) with a GND connection. However, depending on the application, any relay pin can be connected to GND.
4. The fuse shown in oab_au's diagram is necessary. In a car, with a few high current exception, every circuit is protected by a fuse. There are several reasons for that and some of them may not apply to the Bosch Relay mode. But, ask any electrician, it is much easier and cheaper to replace a fuse than melted wires and relays.
5. The fuse protects the circuit that powers the starter solenoid. The relay coil is not part of it so don't count on it to act like a fuse.
Hope it helps,
Elaine

[kwren]

Thanks Elaine for the input!~

Let us know how the "Key contact" worked out!

Keith

[kwren]

Originally Posted by kwren

Thanks Elaine for the input!~

Let us know how the "Key contact" worked out!

Keith

Please!

Keith

[Brian]

Originally Posted by LetItSnow

The battery links straight up to the starter; no need to run a wire to the front of the car when you can throw a ring terminal on a wire and place it on the starter.

I'm not sure I understand what you mean. Could you post a photo or 2 of where the ring terminal would connect up?

[kwren]

Originally Posted by Brian

I'm not sure I understand what you mean. Could you post a photo or 2 of where the ring terminal would connect up?

Take a look at the wiring digram. The BOSCH relay terminal # 30 gets it's power from the battery and requires a 30 amp fused wite running from the battery positive terminal all the way back to the firewall where the relay is, or at least should be mounted. Letitsnow's idea of taping right off the positive battery terminal at the starter as an option is a great one! Needs a fused 30 amp wire fastened to #30 on the relay.

[BoxerFanatic]

I am getting ready to do this...

But I thought if you tapped the positive power for pin 30, from the starter's positive terminal, it didn't require a fuse... but you just say it still does....

I suppose it is cheap insurance to have one there, but it is also a vulnerability for water penetration and such if it truly isn't necessary.

Any clarification there? Maybe I missed something above... if so, I apologize for bringing it back up.

[oab_au]

Originally Posted by BoxerFanatic

I am getting ready to do this...

But I thought if you tapped the positive power for pin 30, from the starter's positive terminal, it didn't require a fuse... but you just say it still does....

I suppose it is cheap insurance to have one there, but it is also a vulnerability for water penetration and such if it truly isn't necessary.

Any clarification there? Maybe I missed something above... if so, I apologize for bringing it back up.

If you tap the power from the starter terminal, there is no need for the fuse. It's only needed if there is a long run of wire to the battery.
I would recommend connecting to the starter terminal.

Harvey.

[kwren]

I would imagine that the referred terminal is the "heavy, from tne battery line directly from the battery. The voltage tapped from that connection directly to the relay and through the relay points directly to the starter in my openion should be fused. But that is just me.

Keith

[oab_au]

Originally Posted by kwren

I would imagine that the referred terminal is the "heavy, from tne battery line directly from the battery. The voltage tapped from that connection directly to the relay and through the relay points directly to the starter in my openion should be fused. But that is just me.

Keith

It depends on how far away the relay is mounted from the solenoid. If it is mounted close, I would not worry about it.
No more that the heavy battery cable that runs to the starter, that is not fused either.
But please yourself.

Harvey.

[Trevor]

Originally Posted by kwren

I would imagine that the referred terminal is the "heavy, from tne battery line directly from the battery. The voltage tapped from that connection directly to the relay and through the relay points directly to the starter in my openion should be fused. But that is just me.

Keith

Keith,

There is no "connection directly to the relay and through the relay points directly to the starter."

As I pointed out much earlier in this thread and on another occasion, the starter cable and the starter starter as a unit are not protected by a fuse, as this is difficult due to the very high inrush current involved. Provided that the connection from the starter terminal to the relay contact is short and mechanically sound, it is no more likely that a short will occur here, than in the main starter circuit. A relay coil short is protected against, via the original wiring.

In fact the additional connection from the relay to the fuse, will constitute the exact same fault path, and the addition of the fuse presents an extra fault path. The mechanical aspects are the deciding factor. Unfortunately the starter cable is, and remains, THE dangerous item in respect of fire.