Bolt for the Starter MGTC

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Uwe Harlos
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Bolt for the Starter MGTC

Post by Uwe Harlos » Mon Jan 31, 2022 11:58 am

Hello all,

I think in my startermotor in the TC is a wrong bolt to hold the two cables.
Can everybody give me the right size?

Thanks very much and be save.

Uwe

bloodysalmon
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Re: Bolt for the Starter MGTC

Post by bloodysalmon » Wed Feb 02, 2022 2:03 am

Hi Uwe, I think you may need to explain your issue a little clearer as I'm not sure which bolt you are referring too as there is only ONE cable from the starter motor to the dashboard :? !
Chris Blood - TC2686& TC3615

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antijam
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Re: Bolt for the Starter MGTC

Post by antijam » Wed Feb 02, 2022 5:59 am

I wonder if he means the battery and ammeter cables ?
Capture.JPG
Capture.JPG (24.09 KiB) Viewed 1508 times
The battery cable is the one secured to the starter with the clip. The ammeter cable is usually routed alongside the battery cable for neatness, although not normally secured with the clip.

Not very clearly shown in this pic...
P1320215-002.JPG
.....but my ammeter lead is secured to the battery cable with heat-shrink sleeving, and is not held by the clip.

Don't remember the bolt size or thread form.

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jddevel
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Re: Bolt for the Starter MGTC

Post by jddevel » Wed Feb 02, 2022 8:45 am

Highly recommend viewing Doug Felton of the frame up video
https://www.youtube.com/watch?v=Fq_1yHFjpgM

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Uwe Harlos
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Re: Bolt for the Starter MGTC

Post by Uwe Harlos » Wed Feb 02, 2022 12:17 pm

Hello all,
I mean the Bolt how goes in the Starter on the front.
In the picture from amtijam where the batteriecable and the amperecable were
hold in the starter.
Thanks for a answer.
Sorry I have no picture.
Regards
Uwe

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Steve Simmons
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Re: Bolt for the Starter MGTC

Post by Steve Simmons » Wed Feb 02, 2022 12:24 pm

Hi Uwe, to the best of my knowledge, that bolt is a 5/16-24 UNF.
1949 TC8975 / XPAG 9609
1948 TC6011 / XPEG1182 (XPAG6472)
http://www.mgnuts.com

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antijam
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Re: Bolt for the Starter MGTC

Post by antijam » Wed Feb 02, 2022 3:21 pm

The unified thread standard wasn't adopted until 1948 and I doubt if it appeared on the TC at all. The thread form is more likely BSW or BSF - although since it's threaded into the block it might still be Metric as on the original Hotchkiss.

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Re: Bolt for the Starter MGTC

Post by Steve Simmons » Wed Feb 02, 2022 4:05 pm

I believe what he's referring to is the bolt that holds the battery cable to the starter, not the bolts that hold the starter to the block. My recollection says it's UNF even though a British thread would seem more likely. When I get a chance, I'll pull a spare starter out and double check.

Edit: Yes, double checked the spare starter and it is indeed 5/16-24 UNF.
1949 TC8975 / XPAG 9609
1948 TC6011 / XPEG1182 (XPAG6472)
http://www.mgnuts.com

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Duncan M
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Re: Bolt for the Starter MGTC

Post by Duncan M » Wed Feb 02, 2022 7:54 pm

It could well be UNF. UNF/UNC adoption was an early (late 40's) attempt at uniformity. The thread was in existence well before the adoption date. The head of the bolt in question does not fit any of the normal British wrenches. While 14mm wrench is a very (overly) tight fit on the head, 9/16" fits just right. If it is UNF, that would seem to make it 3/8" UNF. But, I have not examined the threads, because it is too difficult to remove when the starter is mounted in the car.

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ROGER FURNEAUX
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Re: Bolt for the Starter MGTC

Post by ROGER FURNEAUX » Thu Feb 03, 2022 5:34 am

It is indeed 5/16" UNF - I just checked with a new contact plate. This of course is made of brass, so there is a danger of damaging it with the wrong size bolt, such as 5/16" BSf or "Mad Metric" 8x1.0mm (which is very close!).

Roger

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Duncan M
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Re: Bolt for the Starter MGTC

Post by Duncan M » Thu Feb 03, 2022 8:28 am

So the obscure point of originality on that bolt is that a modern (standardized) replacement bolt of 5/16" UNF will have a 1/2" head, while the early (prior to standardization) original 5/16" UNF bolt had a 9/16" head.

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antijam
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Re: Bolt for the Starter MGTC

Post by antijam » Thu Feb 03, 2022 10:00 am

Ah - I have obviously misunderstood the OP's question (these senior moments are becoming more common :? ) The bolt he's referring to is that arrowed red rather than that arrowed yellow.
bolt.JPG
Apologies. :oops:

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Uwe Harlos
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Re: Bolt for the Starter MGTC

Post by Uwe Harlos » Thu Feb 03, 2022 1:41 pm

Hello all,
thanks for the answers.
I order today a 5/16 UNF-24.
Regards
Uwe

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ROGER FURNEAUX
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Re: Bolt for the Starter MGTC

Post by ROGER FURNEAUX » Fri Feb 04, 2022 4:11 am

It is indeed 5/16" UNF - I just checked with a new contact plate. This of course is made of brass, so there is a danger of damaging it with the wrong size bolt, such as 5/16" BSf or "Mad Metric" 8x1.0mm (which is very close!).

Roger

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Uwe Harlos
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Re: Bolt for the Starter MGTC

Post by Uwe Harlos » Mon Feb 07, 2022 11:34 am

Hello all,

I want give you a feedback.
Yes it is a 5/16 UNF.

Thank you

Uwe

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