Flywheel sizes

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Slartibartfast
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Flywheel sizes

Post by Slartibartfast »

Hello everyone, this is my first time here, and my first post :D

I am a marine engineer, living in France, who has spent far too much time and money playing with Land Rovers. I am now in the process of repairing a 1956 M-M (my first M-M) for a friend. The starter ring was completely knackered and I asked her to buy another based on the year and 803. When it turned up it was too small in diameter by about about 4mm. The OD of the flywheel where the ring sits is 236.6mm, the ID of the ring is 232.5mm. My question is this : Can anyone tell me what is the correct part number for a starter ring that is suitable for the flywheel so that I can get one ordered.

Thanks in advance
Slartibartfast
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Re: Flywheel sizes

Post by Slartibartfast »

So at the same time as I posted here, I sent an e-mail to Moss and they have kindly provided the following :

The 12G290 ring gear for the 1098cc engine has the following specs.

NUMBER OF TEETH = 104
I/D = 235.70/235.90 MM
O/D 264.90/265.40 MM
THICKNESS = 12.60/13.10 MM
CHAMFER = LH CUT 45 DEGREES
NON ENGAGE STEP 236+/-0.05 MM
STEP THICKNESS 4MM

I hope this might be of use to someone in the future.

According to the V5 it's an 803, but now I'm not so sure seeing as the engine serial does not match the V5 either.
les
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Re: Flywheel sizes

Post by les »

Quite a comprehensive specification they have provided, thanks for forwarding, as you say it may be useful to someone.

philthehill
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Re: Flywheel sizes

Post by philthehill »

A photo of the distributer side of the engine would be helpful.
The 803cc engine has the oil filter element screwed directly to the block. The 948cc and 1098cc engines have the oil filter attached to the block by a separate housing.
If your engine is indeed 803cc this is the flywheel ring gear you will need.
https://www.morrisminorspares.com/engin ... ls-p830254
The internal diameter of the ring gear is slightly smaller than the external diameter of the flywheel so to fit the ring gear you have to heat and expand the ring gear to enable it to fit over the rim of the flywheel.
The 1098cc flywheel is different to the 803cc and 948cc flywheels and requires a different ring gear so for completeness here is the link to the 1098cc flywheel ring gear
https://www.morrisminorspares.com/engin ... ls-p830255

Slartibartfast
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Re: Flywheel sizes

Post by Slartibartfast »

The oil filter is in a housing bolted to the block, so not an 803. Original serial number has been machined off the block, so not much use. I have ordered the ring gear referenced above as the ID is roughly 1mm smaller than the OD of the flywheel which would make sense.
I'll update when the ring gear turns up.
philthehill
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Re: Flywheel sizes

Post by philthehill »

Thank you for ruling out the 803cc engine.
I would advise that before you order - the 1098cc engine has a block casting number of 12A497 and which can be found on the side of the block below the rear valve chest cover. If the numbers do not match 12A497 you have a 948cc engine and you will need the
https://www.morrisminorspares.com/engin ... ls-p830254
Good luck.

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