What and How is this fixing intermittent no start, .. Mayo Performance solution Options

[Literati914]

My friend took his car to Ed Mayo of Mayo Performance to fix a no start after driving issue. Ed has been working on these cars since new and he knew exactly what the trouble was. He installed the item in the following picture and all is well now. He said they even used to have to do this to NEW 914s back in the day!

He explained it to my friend who only caught bits of the explanation. Something along the lines of the wire to the starter getting hot and needing a 1/2 volt extra from this add on, to overcome the issue.

I assume it’s the typical heat related issue. BTW I think a lot of people assume vapor lock is the only heat related problem (fuel pump is in the front on this car). Can someone give a thorough explanation for what this is addressing and how? I’d love to see a wiring scheme of this fix also.

[Shivers]

The hot start kit. Mine uses a Bosch relay it bypasses the long skinny wiring running from your ignition switch to the starter. By using a dedicated, shorter wire directly from the battery, the relay, triggered by the ignition switch ensures the starter solenoid receives the full voltage it needs to engage the engine even when hot and suffering from electrical resistance.

@Literati914

[brant]

Very common

I have the same Bosch
The other more common similar solution is the ford relay which I’ve also used repeatedly

[JamesM]

I view these as more of a band-aid. Yes they are a solution but if you properly address the underlying problem its unnecessary.


I have had my hands on a LOT of 914s, never had to install a hot start relay, and in fact have removed quite a few of them.

Underlying issue is usually voltage drop at the ignition switch contact, crappy starter solenoid, or both.

I find the solenoids used on the modern gear reduction starters to be a lot less temperamental than the ones used on the factory/rebuilt starters.

[ClayPerrine]

I know Ed Mayo personally, and trust him implicitly. A lot of what I know about 914s I learned from Ed.

And that was the factory fix for the "hot start issue" in a 914. Installing one will fix that issue, and also make your ignition switch last longer because it doesn't have to carry as much of a load.

But with modern gear drive starters, I have found it to be unnecessary. But it will still make that damned cheap Brazilian ignition switch last longer.

[Superhawk996]

I view these as more of a band-aid. Yes they are a solution but if you properly address the underlying problem its unnecessary.


I have had my hands on a LOT of 914s, never had to install a hot start relay, and in fact have removed quite a few of them.

Underlying issue is usually voltage drop at the ignition switch contact, crappy starter solenoid, or both.

I find the solenoids used on the modern gear reduction starters to be a lot less temperamental than the ones used on the factory/rebuilt starters.

(IMG:style_emoticons/default/agree.gif)

I have seen excessive voltage drop on the yellow stater wire multiple times as a root cause. The source of the voltage drop has always been at one end termination or the other. I have yet to find one where I had to replace the actual wire. I’m sure someday I’ll find one where the actual wire needs to be replaced but haven’t encountered that yet.

The core problem is the inability of most shops and DIY’ers to be able to properly diagnose and repair wiring issues.

Other issues this quick fix often hides . . . For a while.

Bad ground from trans to chassis (often sourcing ground thru clutch cable - leading to eventual breakage of the clutch cable).

Bad negative ground cable from battery to chassis

Extreme corrosion between the starter itself and the transmission (ie another bad ground)

Bad positive battery cable to the starter lug.

[Ninja]

The relay allows your 50+ year old wiring system to provide the same (or better) power at your device than it had when brand new.

It's not just for starters.

I've relayed blower motors, audio systems, wiper systems, head light elements, fuel pumps, and a shitload of starters.

Anything mid amperage flow and above will live longer with a relay in it IMO.

Pretty much everything since the mid 80s have added relays for all of the above.

Most of my diagnosis procedures start at the relay box now-a-days and it's faster.

The relay ALSO protects your 50-year-old circuit from running heavy amperage loads through it.

This is especially helpful with ignition and headlight switches.

Absolutely Ninja approved! (IMG:style_emoticons/default/ninja.gif)

Only reason in my book for not using a relay is originality.

Source I've used for Bosch relays in the past.

https://www.waytekwire.com/catalog/relays