Lancia Motor Club

Model Technical and Interest => Lambda => Topic started by: davidwheeler on 30 April, 2019, 08:48:14 AM



Title: Starter ring gear
Post by: davidwheeler on 30 April, 2019, 08:48:14 AM
To save me taking off the flywheel, can anyone please tell me the outer diameter of the starter ring gear?   I am told that the teeth are not suitable for building up by welding so I am wanting to see if I can find a gear on line or, failing that, going to my local Church clock repair shop to see if they can make one (or several).


Title: Re: Starter ring gear
Post by: Dikappa on 30 April, 2019, 06:28:37 PM
I went to measure mine, it measures 396mm and seems to be in pretty healthy condition.


Title: Re: Starter ring gear
Post by: davidwheeler on 01 May, 2019, 09:34:13 AM
Aren't you lucky!  Thank you.   I make it 136 teeth.
But that is my replacement gear - the original is 130.


Title: Re: Starter ring gear
Post by: Dikappa on 01 May, 2019, 06:28:03 PM
You want a tooth count David?



Title: Re: Starter ring gear
Post by: davidwheeler on 02 May, 2019, 04:44:54 PM
32!   I can count them myself thanks and I did once but have forgotten.   The pitch and depth are more important and I have measured those as 9mm pitch, 7mm depth and 19mm length.  Anyway, I make it 130.


Title: Re: Starter ring gear
Post by: Mikenoangelo on 02 May, 2019, 08:07:23 PM
Careful - metric gears are identified as "Module" not pitch. You'll need to Google a bit to understand (excuse me if you already do!) but I suspect what you have is a gear of Module 3 which would give 130 teeth on a pitch circle diameter of 390mm (overall diameter 397 less 2 times 1/2 the tooth height = pitch circle diameter). If you work out the tooth "pitch" on the PCD that would agree with your 9mm. A replacement gear would most likely be listed as Module 3 x 130 teeth. Obviously check before you buy!

Mike


Title: Re: Starter ring gear
Post by: Dikappa on 03 May, 2019, 05:08:59 AM
Would it not be more cost effective to make the drawing and have a ring water jetted?  Off course there would be some grinding to to....


Title: Re: Starter ring gear
Post by: Mikenoangelo on 03 May, 2019, 03:36:04 PM
Be aware if you do commission a new ring gear that there is more than one tooth profile on these. I had a ring gear made by Freedom Engineering near Hull and they found that the original teeth were what they described as "stub profile". Best if you do get one made, to borrow an original flywheel to show to the machinists. It might also  be a good idea to have it induction hardened.

Mike


Title: Re: Starter ring gear
Post by: davidwheeler on 04 May, 2019, 08:30:12 AM
I have just enquired of a firm in New Zealand who have gears of 393mmOD but you may be right, it could be better to get one made.    I have a friend who works in a shop that rebuilds church clocks and may well have machines big enoug.  Would anybody else be interested?


Title: Re: Starter ring gear
Post by: Dikappa on 12 May, 2019, 02:17:00 PM
Preparing some bits for the engine I just put the two flywheels I have here next to each other, and: surprise surprise they are VERY different!

The reddish painted one carries the number 1326 so I suppose it's a rather early one.
The black (read dirty) one has number 6792 stamped into it, which would make it a 7th series flywheel.  It seems to have a shrinked on gear ring, as opposed to the red one.
It is also a few mm smaller in diameter.

Reading in Bill Jamiesons Lambda Bible reveals however only the sixt series cars fitted with Magneti Marelli starter had a detachable starter gear ring.

Any comments to the puzzle most welcome.

@David: is your car a late series car, as then a starter gear ring would be nice, seen the black one has some wear...so please keep me posted of the progress...





Title: Re: Starter ring gear
Post by: Dikappa on 13 May, 2019, 05:32:10 AM
@ David: re-reading your comments I reckon the 393 mm ring from New Zealand might be right...