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Lets talk starter motors....


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Got mine off today (guide coming soon).

All seems to be fine, just a little confused on how the things work....if you know how they work (or dont work) you know how to fix it.

OK refer to drawing.

Red/white wire is the switched 12V from the battery from the ignition relay...when key is in position 3 this relay closes and the red/white wire becomes live.

There are 2 coils inside the starter body. One I assume is the electromagnet that forces the gearing forward into the flywheel (A), the other seems to be a loop that goes to the motor itself (B). Obviously the body if the unit is grounded.

My starter is just clicking, so I can assume that coil A is fine, certainly meters out as low resistance, but so does could B....I can't understand why B isn't supplying the motor to turn...all the connections are good.

Again I assume the gears should be thrown forward before the motor turns...how does this work ?

Only thing I can think of is that A has gone a little short on the windings and is dumping too much current to earth which is starving the motor from turning. There was a fair bit of rust in there too !

Anyone shed some light on to exactly how this thing should work ?

I've done some test but I am a bit reluctant to connect this upto the battery incase there is a short circuit somewhere.

Edited by Jonathan

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Its been a long time since I studied this at college, but here goes:

refer to the cross section diagram of a pre-engaged starter

The windings on the top solenoid (called a piggyback solenoid for obvious reasons) are energised (must be by the red/white wire), causing an electro-magnetic force which attracts the solenoid plunger.

As this is connected to the pivoted pinion fork (pinion engaging lever!), it moves the pinion into mesh with the flywheel ring gear.

Only when it is fully engaged is the travel sufficient to close the heavy duty contacts and allow current to be transmitted to the motor its-self.

When the red/white wire is de-energised, springs return everything back.

Have you tested it on the bench to see what happens?

Use jump leads to connect the earth (body of starter to batt negative)

and the batt positive to the large copper threaded stud furthest from the starter.

Then get a small wire and flick the positive to where the red/white wire fits.

BE READY, IT WILL JUMP OF THE BENCH SO BE AWARE

When you know what to expect, hold the small wire on.

Does the pinion move forwards and not turn?

Hope this is of some help

Glyn

Got mine off today (guide coming soon).

All seems to be fine, just a little confused on how the things work....if you know how they work (or dont work) you know how to fix it.

OK refer to drawing.

Red/white wire is the switched 12V from the battery from the ignition relay...when key is in position 3 this relay closes and the red/white wire becomes live.

There are 2 coils inside the starter body.  One I assume is the electromagnet that forces the gearing forward into the flywheel (A), the other seems to be a loop that goes to the motor itself (B).  Obviously the body if the unit is grounded.

My starter is just clicking, so I can assume that coil A is fine, certainly meters out as low resistance, but so does could B....I can't understand why B isn't supplying the motor to turn...all the connections are good.

Again I assume the gears should be thrown forward before the motor turns...how does this work ?

Only thing I can think of is that A has gone a little short on the windings and is dumping too much current to earth which is starving the motor from turning.  There was a fair bit of rust in there too !

Anyone shed some light on to exactly how this thing should work ?

I've done some test but I am a bit reluctant to connect this upto the battery incase there is a short circuit somewhere.

<{POST_SNAPBACK}>

Edited by glynherron
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Please explain to me how to put the attached document as a thumb nail, i've tried three times and its now getting embarrasing!!!!!!!!

Its been a long time since I studied this at college, but here goes:

refer to the cross section diagram of a pre-engaged starter

The windings on the top solenoid (called a piggyback solenoid for obvious reasons) are energised (must be by the red/white wire), causing an electro-magnetic force which attracts the solenoid plunger.

As this is connected to the pivoted pinion fork (pinion engaging lever!), it moves the pinion into mesh with the flywheel ring gear.

Only when it is fully engaged is the travel sufficient to close the heavy duty contacts and allow current to be transmitted to the motor its-self.

When the red/white wire is de-energised, springs return everything back.

Have you tested it on the bench to see what happens?

Use jump leads to connect the earth (body of starter to batt negative)

and the batt positive to the large copper threaded stud furthest from the starter.

Then get a small wire and flick the positive to where the red/white wire fits.

BE READY, IT WILL JUMP OF THE BENCH SO BE AWARE

When you know what to expect, hold the small wire on.

Does the pinion move forwards and not turn?

Hope this is of some help

Glyn

<{POST_SNAPBACK}>

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Good info - It's not quite how the Esprit starter works but same princial.

When the red/white gets live it supplies a large coil with a plunger inside it which moves forward when the coil is energised. This forces the gear forward and the spiral cut internal shaft rotates it slightly (is that the bendix ? cen't remember).

See photo.

Motor runs fine, and its actually quite fun shooting the spring 2-3 feet across the room by energising the coil ;)

Gonna do a refurbish guide now before piecing it back together and seeing whats what again.

Edited by Jonathan

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Changing the starter on my S3 was the first job i did on Esprits, easy!

;)

remember the new LOTUS oil filters are bigger, so the larger starters

foul them (i cannot remember but either the starter i fitted or the one

i took out was bigger, i think the latter as it's been serviced since many

times, ask Terry).

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Got mine off today (guide coming soon).

All seems to be fine, just a little confused on how the things work....if you know how they work (or dont work) you know how to fix it.

OK refer to drawing.

Red/white wire is the switched 12V from the battery from the ignition relay...when key is in position 3 this relay closes and the red/white wire becomes live.

There are 2 coils inside the starter body.

Edited by PVK 596Y
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Haha another Maistone-ite !

Not actually in Maidstone, little town outside called Aylesford - keep going out towards West malling on the A20 and my house is almost directly opposite 'teapot lane' on the A20 itself on the Aylesford / Ditton border - if you're in the area gimme a shout - pop round for a coffee, love to see the Griff - I used to have a Probe too :)

Got it all reconned and back together - tbh I was totally overlooking the main motor contact on the plunger. Actually a really easy 1 day job if you have the right tools.

Engine now starts nicely but when the thing fires up there is this horrible sound - I suspect this is when the motor picks upto the engine revs....bench test was fine, turns the engine with the plugs out lovely too.....bizzar, couldn't find a fault with it (although I have a spare rubber washer now...oops) but it allows me to have a drive at least.

EDIT: Just looked at some of my pictures from inside the engine bay and you can clearly see wear on the flywheel teeth closest to the starter motor. Can't understand why, bench test showed the starter fully engaging forward (or it wouldnt turn) - there is slight wear on the starter gear as well....any reason for this, is it normal ? I guess when I have to have a new clutch the flywheel might need looking at.

Edited by Jonathan

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Haha another Maistone-ite !

Not actually in Maidstone, little town outside called Aylesford - keep going out towards West malling on the A20 and my house is almost directly opposite 'teapot lane' on the A20 itself on the Aylesford / Ditton border - if you're in the area gimme a shout - pop round for a coffee, love to see the Griff - I used to have a Probe too  :)

Hi, I know Aylesford well, I live in Penenden Heath, off Sandling Lane.

You can't be more than 5 miles away.

I'll take you up on your offer of a coffee some time, as long as you don't mind me drooling all over your GT3.

I hope to acquire an S4 in the not too distant future, but it means selling the Griff first to raise the cash.

Anyway, look forward to meeting you some time.

Paul.

PS I went to the Oxford run a few weeks ago, and someone said they were from Eccles. Do you know them?

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Ahh you went to Oxford as well in the TVR ?

I was piloting in the Elise :)

Don't know who was from Eccles though...

If you wanna go car hunting sometime lemme know (I'll bring me gun hehe). Def bring the Griff round though, my uncle used to have one, I'm a fan tbh, pity you have to sell it :)

Feel free to pop by and have a look at the GT3 anytime, very similar the S4 apart from the interior and slight drop in performance but essentially very similar - mine's not in A1 condition (yet) so it'll give you a good idea of what goes wrong / what to look for. My phone number's on my sig :)

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Ahh you went to Oxford as well in the TVR ?

I was piloting in the Elise  :)

Don't know who was from Eccles though...

If you wanna go car hunting sometime lemme know (I'll bring me gun hehe).  Def bring the Griff round though, my uncle used to have one, I'm a fan tbh, pity you have to sell it  :)

Feel free to pop by and have a look at the GT3 anytime, very similar the S4 apart from the interior and slight drop in performance but essentially very similar - mine's not in A1 condition (yet) so it'll give you a good idea of what goes wrong / what to look for.  My phone number's on my sig  :)

<{POST_SNAPBACK}>

We were late leaving home, and arrived at Peartree Services just as the convoy was leaving. Someone kindly gave me a copy of the route, which we followed, but cut out the loop. We arrived at the hall ahead of most of the group and parked just beyond the Esprit parking area and to the right, so out of sight of the main group. There was another Griff there that actually was part of the convoy. Mine was the dark blue one.

I'm only about 80% sure I want to swap the griff for an Esprit, so a change of heart is possible (I used to be indecisive but now not so sure etc :) ).

I owned a very good S3 in the late 80s (it was only 5 yrs old then) and have some nice memories of Esprit ownership, which may help tip the balance.

Will be in touch.

Cheers,

Paul.

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