Page 1 of 1

Bolt for the Starter MGTC

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

Re: Bolt for the Starter MGTC

Posted: Wed Feb 02, 2022 2:03 am
by bloodysalmon
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 :? !

Re: Bolt for the Starter MGTC

Posted: Wed Feb 02, 2022 5:59 am
by antijam
I wonder if he means the battery and ammeter cables ?
Capture.JPG
Capture.JPG (24.09 KiB) Viewed 3816 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.

Re: Bolt for the Starter MGTC

Posted: Wed Feb 02, 2022 8:45 am
by jddevel
Highly recommend viewing Doug Felton of the frame up video
https://www.youtube.com/watch?v=Fq_1yHFjpgM

Re: Bolt for the Starter MGTC

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

Re: Bolt for the Starter MGTC

Posted: Wed Feb 02, 2022 12:24 pm
by Steve Simmons
Hi Uwe, to the best of my knowledge, that bolt is a 5/16-24 UNF.

Re: Bolt for the Starter MGTC

Posted: Wed Feb 02, 2022 3:21 pm
by antijam
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.

Re: Bolt for the Starter MGTC

Posted: Wed Feb 02, 2022 4:05 pm
by Steve Simmons
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.

Re: Bolt for the Starter MGTC

Posted: Wed Feb 02, 2022 7:54 pm
by Duncan M
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.

Re: Bolt for the Starter MGTC

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

Re: Bolt for the Starter MGTC

Posted: Thu Feb 03, 2022 8:28 am
by Duncan M
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.

Re: Bolt for the Starter MGTC

Posted: Thu Feb 03, 2022 10:00 am
by antijam
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:

Re: Bolt for the Starter MGTC

Posted: Thu Feb 03, 2022 1:41 pm
by Uwe Harlos
Hello all,
thanks for the answers.
I order today a 5/16 UNF-24.
Regards
Uwe

Re: Bolt for the Starter MGTC

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

Re: Bolt for the Starter MGTC

Posted: Mon Feb 07, 2022 11:34 am
by Uwe Harlos
Hello all,

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

Thank you

Uwe