348 "Hot Starting" relay. Worth it?

My car has an aftermarket battery kill switch in the engine bay (fitted by others) . It isolates only the supply to the starter motor – so in effect its kind of like an extra bit of security because its got a removable key – a key I don’t keep with the car. (the rotary jobbies with the red removable switch you see on the outside of saloon race cars)

On Thursday it failed in the open position.

Now I’ve never been happy with its aesthetic, but haven’t sorted out getting one of the original terminal blocks because I like the additional security. Its simple , like me.

So on Saturday I replaced it - but I still think its ugly and poorly mounted.
(but my concern on Saturday was finding the fault – and was really pleased
a) it was something simple,
and b) it wasn’t anything intrinsically - and for that read expensive - wrong with the car)


However, I’ve read of and know others have fitted, an additional relay to the starter motor circuit to cope with a supposed “Hot Starting Issue” and to reduce volt drop onto the ignition switch circuit, and reduce electrical wear through the ignition switch.

(ie a relay whose coil is energised by the key, but the switching, and hence the control circuit through the starter solenoid is done by a new "fresh" circuit)

So… given that I want to sort the appearance of this switch out. I <could> fabricate something enclosing both the switch and a relay for the hot start thing OR just something for the switch.

So my question – given that I have never had a hot starting issue, and my car fires first pull every time, always has, – is there any point/advantage in pre-emptively fitting this relay? It is just something else to go wrong, unless it delivers real benefits.

And thinking it through, had this issue occured at the "roadside" I could easily have bridged the switch out and got going again. A relay failure and I'd have been stuck.

 

Just for clarification - there's 2 main sarting problems - the "hot start" problem where the starter turns but the car doesnt "catch" and start which is caused by lack of grease in the flywheel.

The relay fix is to fix intermittent non starts where the car doesn't even turn over which can occur randomly whether hot and cold.

 

Ah , right, thanks for that, Jeff.

My car has only ever failed to start once - due to this additional switch, so have not done much research on non-starting hot or cold. - but I guess my question remains - given I have to do something, is it worth adding the relay for precautionary reasons....?

I guess the risk is adding a potential source of unreliability, but the reward is reducing the load, and hence prolonging the life of my ignition switch.

 

One of the hard start problems with 348s is due to bad grounding, dirty wiring connections and the bullet disconnector switches. The starter doesn't turn and it makes a clicking noise. It happens when the starter receives lower voltage than needed, and it does not engage. That relay helps with this issue, and cleaning the grounds and connections helps too.

As you said, your car starts always at once. So, IMO if it's not broken don't fix it.

It's seems that your 348 has a propperly working electrical system. Just keep the grounds and connections clean and rust free for you still having fun.

 

Thanks, thats good advice.

In my experience, when working on these cars, making good electrical connections fixes many "faults" and only relatively rarely do I need to raid a parts bin.

As for adding an extra relay, I think, on reflection, why fix what isnt broken? I'll leave it be (though maybe if I do make an enclosure for this switch, I'll make sure I dont close any doors to future needs)