7 replies to this topic

[Haynes]

I have an inertia starter and a solenoid with the start button in the engine bay, most bits and pieces including the loom, starter and ring gear are new as its been a full rebuild. 

 

If you turn the key and it starts instantly then its fine.  However sometimes you turn the key and it just goes whrrrrr, ie it doesn’t keep cranking, more like it spins once then stops.  

 

Is this normal behaviour for an inertia starter?

Does the starter disengage or is power cut once the engine fires? 

Or should you be able to keep cranking it over and over until it starts (which is what I would expect)?

 

If you use the solenoid button, ignition off, then it will keep turning and if you take all the plug caps off then the key will keep turning it over.  From this im assuming that it is something to do with it firing or attempting to start that’s causing the problem rather than the starter not working.

 

If this isn’t right, any clues as to what the problem might be?

 

 

 

[Lplus]

I have an inertia starter and a solenoid with the start button in the engine bay, most bits and pieces including the loom, starter and ring gear are new as its been a full rebuild. 

 

If you turn the key and it starts instantly then its fine.  However sometimes you turn the key and it just goes whrrrrr, ie it doesn’t keep cranking, more like it spins once then stops.  

 

Is this normal behaviour for an inertia starter?

Does the starter disengage or is power cut once the engine fires? 

Or should you be able to keep cranking it over and over until it starts (which is what I would expect)?

 

If you use the solenoid button, ignition off, then it will keep turning and if you take all the plug caps off then the key will keep turning it over.  From this im assuming that it is something to do with it firing or attempting to start that’s causing the problem rather than the starter not working.

 

If this isn’t right, any clues as to what the problem might be?

Sounds like it fires on one cylinder and this kicks the inertia gear out of engagement.  When you disconnnected the spark or removed the plugs it wouldn't fire that one time so stays in engagement.

[Haynes]

I've just been out to start it. This time I turned ignition on and used the button on the solenoid rather than the key. It behaved 'normally' the starter kept turning over as it started up.

Seems to me that somehow the ignition key isnt getting it to crank as much as the button, or releasing prematurely.

[Spider]

If what Lplus described isn't occurring, then it's possibly a worn Ignition Switch.

[Ethel]

Ignition switches are worked pretty hard without a relay. When the solenoid switches in the starter motor the voltage will drop because much more current can flow through the chunky cables & motor - it's what ballasted ignition is supposed to emulate, so you can use a coil optimised for starting when the engine is running without melting stuff. If the ignition switch contacts are on the way out, there might not be enough oomph going through them to hold the solenoid closed when the motor hogs all the juice.

 

With an inertia starter, once the engine has started, it will turn the ring gear faster than the motor can, which will screw the drive pinion back up the bendix gear until it disengages. Of course, if you don't let go of the key it'll try to reengage & the clatter of the pinion & ring gear will let you know about it!  

 

We might be wrong - a poor earth through the solenoid mounting screws can do the same,

[Haynes]

Thanks for replies so far, ill try a new ignition switch, its the dash mounted type.  Or can they be repaired??

 

I did have problems with the earth to the solenoid when i first put everything together but thats sorted.

[Ethel]

The ignition switch connector block is pretty accessible  below the column cowl you could unplug it and do some hotwiring to eliminate just the switch. They can be pried open for a spot of Macgyvering, but replacement would be preferable. Adding a relay might squeeze some extra service out it, and a replacement if it comes to it..

[coopertaz]

consider relay to feed solenoid anyway as future proof