Bomb Type Starter?

[John Morrison]

Back on some mechanical stuff on my very long term 3A project - as a change from tin bashing, and looking at the starter etc.

Original is Bomb Type, with all that goes with it, and I'm wondering about folks experience of these as opposed to the exposed Bendix Type, 

of which I have stock!

I can leave as is, and hope the bomb type behaves, I can buy a High Torque or I can switch out to four speed synchro box, ring gear

and Bendix type, which would align with my TR4 mechanicals.

What would others do?

Cheers

John.

 

[Trumpy3]

John

For what its worth. I would do what ever it took to dump the bomb type if you plan to use the car often. At least that's my experience. If you are using TR4 mechanicals then a Bendix would be a good choice but I would go for High Torque as it's much kinder on the ring gear and battery.

The flywheel you use will play a big part of course as the early flywheel is only suitable for the bomb or HT. The latter flywheel is only suitable for the Bendix or HT.

Brian

[Richardtr3a]

My TR3A is 1958 with o/d and original gearbox.  I fitted a special new starter from Cambridge Motorsport and it has worked very well.  I made a small access panel in the gearbox cover to make access to the top bolt easy. I have got to the point where I am no longer nervous when starting the engine. This is a very unusual position. 

I have other problems  but the starter is in good working order.

Richard & B

[Lebro]

I thought the Bomb type was only for flywheels with shrink on ring gear, which (I had thought) would only have been 2's & early 3's ? anyway make sure you get a starter with the right No. of teeth to match the ring gear - 9 teeth for shrink on, & 10 for bolted.

FWIT I am running shrink on with a WOSP 9 tooth geared motor. & like it !

Bob

[BlueTR3A-5EKT]

The early flywheel with shrink on ring gear is a good 10 lb lighter than the later with bolt on ring gear.  I run same as Bob  -  Original Shrink on ring gear type flywheel, drilled for later diaphragm clutch mated to a Race Mettle lightweight geared starter.  https://www.racetorations.co.uk/product/high-torque-starter-motor-triumph-tr2-3-morgan-4-shrink-on-ring-gear/

 

[Lebro]

Mine is a GT6 diaphram clutch from TR Shop. still going well after 10 years, & many K's of miles. didn't bother changing it 2 years ago when engine was rebuilt, as it had no discernable wear.

Bob

[ewan2]

I ran the bomb starters in my TR2 for years but when they failed the replacement reproduction sleeves with bonded rubber failed a number of times in not many miles.

To save the effort replacing the starter often. I installed an HT starter which turns the engine over quicker and has been fine apart from it does not sound the same.

I would recommend an HT starter.

 

Ewan 

[John Morrison]

 

On 11/30/2023 at 9:03 AM, Trumpy3 said:

John

For what its worth. I would do what ever it took to dump the bomb type if you plan to use the car often. At least that's my experience. If you are using TR4 mechanicals then a Bendix would be a good choice but I would go for High Torque as it's much kinder on the ring gear and battery.

The flywheel you use will play a big part of course as the early flywheel is only suitable for the bomb or HT. The latter flywheel is only suitable for the Bendix or HT.

Brian

Thanks for the replies guys.

I guess my initial thoughts on this would be as above, and although my car is TS 58000 and a 1960 car it does have the bomb type and also the gearbox for the bomb type, I haven't removed the clutch yet (Minus 7 in Cumbria last night!) one would suppose it would be the shrink on ring gear.

It looks like my plans to keep all original, as far as possible, have been scupperred as, I've got all the stuff to convert to later flywheel, starter and 4 synchro box on the shelf.

That looks the way to go, shame as the three synchro box looks perfect, but it will keep the TR3A and the TR4 'The same' plus spares will be common to both cars, seems long term sensible.

Can anyone see a downside to this thinking?

John.

[iain]

I use an original bomb starter, rebuilt in 1979......fingers crossed :-)

[Tony_C]

Hi John, mine is a very late and very original 3A, I’ve run with the bomb starter for the 40+ years I’ve had the car (far as I know it looks original fitting) only ‘trouble’ I’ve ever had was fairly recently when after a lot of cranking I did not disengage… scared me but, I think that was more down to a flat battery and other circumstances although, I did then fit an isolater  which I had been planning but never got around to 

[ianc]

I recall that, sometime in the 1960s, my TR2 shredded its bonded rubber, and I fitted a replacement.

However, if I had a bomb type now and it failed, I would fit a modern geared type - as I have had on my TR4 for quite some years.  But be careful which type you choose as some have proved troublesome (search the Forum for advice).

Ian Cornish

[Lebro]

Can I just mention that I have a good Bomb motor for sale (no sensible offer refused!) I had to go the geared type when I fitted a SS exhaust manifold, the Bomb would no longer fit.

Bob