Talk Morgan Forums Morgan Sports Cars Maintenance & Servicing Steering Column Spline Count

OK folks, it's not good news I'm afraid!

The 48-spline Optimill hub I purchased is designed for a steering shaft diameter of approximately 19mm (a 3/4" shaft), while the 36-spline variant is designed for a shaft diameter of approximately 16mm (a 5/8" shaft).

Sadly neither will work, I'm now finally with the car taking measurements and it appears I have a steering shaft that measures exactly 15mm and also seems to have 30 splines, or possibly 29 as hard to count with complete accuracy. I can also confirm there is no master spline, it definitely looks like I will need need a specific hub designed for the 15mm-30 spline configuration, which is a far less common fitment than the two standard Defender options offered by Optimill.

It needs further investigation but I believe in the world of Land Rover components what Morgan used on my 2012 Plus 4 is known as the metric "Fine Spline" 15mm-30 column, or I guess it could be a 19/32-29 spline shaft? As advised above, I'll reach out to Melvyn Rutter on Monday and see where that takes me?

Oh well, it was worth a try, the Optimill QR hub is a thing of engineering beauty but I always accepted there was a risk in buying aftermarket Land Rover parts for a Morgan. In my defense, I was encouraged by the Berrybrook Morgan listing showing an Optimill QR hub, and a chat I had with then over a year ago that all suggested one of the Optimill options would work.

Of course the moral of the story is.... Measure twice, buy once



NB: Decided to polish the wheel to cheer myself up, it came up lovely

Hi all,

I phoned Melvyn Rutter, he was super polite and wanted to help but despite his encyclopaedic Morgan knowledge he couldn’t confirm the shaft diameter or the spline count. I also spoke with Brown & Geeson Ltd who make a range of QR hubs, but unlike the Optimill that is internally splined direct fit, the BG versions are the bolt on type designed to use in conjunction with your existing hub so that isn’t going to work for me as I'm trying to achieve a shorter hub, not a longer one.

However, Luis from Brown & Geeson Ltd did have a steering column reference spreadsheet with a host of data on it, consulting it confirmed the 15mm shaft used by Morgan in the 2011/2012 period was almost certainly a Rover part, more specifically this 15mm shaft actually has 29 splines and was used on the Land Rover Freelander, the Rover 200,400,600 and the MGF.

In this case, knowing the origins of the shaft doesn’t really help as none of the cars it was used on are typically fitted with a quick release steering wheel. I did also get an email back from Optimill to say they are too busy to create a custom drilled and internally splined hub in 15-29 so it's now looking like I'll have to abandon the quick release idea all together.

The only shorted hub option that should bring the stalks back to where they were with the flat wheel and give me back the lost entrance gap is Moto Lita's part number B71J, obviously that's a fixed hub not quick release, however it should work as it seems highly likely it was specifically designed for post 2007 Morgan owners who are fitting one of their dished steering wheels.

The best solution I've come up with so far is to buy a Momo (MK4928R) steering wheel boss designed for an MGF, with the four collapsible fingers removed I'm left with a plate that has the correct 15-29 internal spline set in it.

https://momo-uk.co.uk/Momo-hub-boss-steering-wheel-kit-MK4928R

The plate appears to be approximately 10mm thick, so it won't add much length once safely bolted up to the column half of my Optimill, this will just need to be drilled and tapped accordingly to take a suitable number of countersunk high tensile machine screws.

I've also just found the following post where Heinz confirms what I've separately discovered, i.e Morgan used a Rover 200/400 steering column shaft which is definitely 15mm in diameter with 29 splines. Here we can see him fitting a Momo wheel, its possible if he'd bought a Momo (MK4928R) steering wheel boss designed for an MGF he could have saved the machining work?

https://www.talkmorgan.com/ubbthreads.php/topics/338887/Momo_Prototipo_fitted_for_4/4#Post338887

Blimy Dave what a faf it's turned out to be. Guess all the 15-29 shaft cars were just too complex in their steering wheel interactive modes to make that change possible, so no demand for the boss. I have definitely seen a Morgan with a QR wheel and your discovery of the MOMO option might explain it as the racing world use MoMo as their no. 1 choice.
You're right about the Optimill quality though, They really are so well made and to a high tolerance and the anodising depth is truly impressive. I think when my Defender drove out of my life for the last time with the very lucky new owner at the wheel it was the security cover in bright orange sitting on it's mount on the centre consul that almost finished me. I had quite a few Optimill parts amongst other upgrades. I absolutely loved my Defender and did not want to part with it but finding myself in my mid sixties, even with all the equipment I could possibly need everything just got to be too heavy! and I knew the writing was on the wall.

By the way, failing to engage the brain isn't all bad....... well, I'm finding it helps keep things fresh, Despite having done most things on the Mog innumerable times it all has a sense of discovery once more.....!

Martin.

Thanks for following the journey Martin!

There really is no substitute for measuring up before buying a part, however, the 36 spline Optimill wouldn't have fitted Monty either. If I had taken measurements in advance, I probably would have aborted the project when the 15-29 shaft dimentions revealed themselves.

As it stands, and having now seen how well made the Optimill is, I was motivated to find a solution and to that end I've been able to locate a Momo (MK4928R) steering wheel boss designed for an MGF, I located it by joining the Facebook MGF parts group, posting a simple wanted message turrned up the correct part in under an hour. I then agreed a deal with the seller of £25 including postage, a good saving over £90.00 which was the very cheapest price I could find it elsewhere online.

It's new/old stock, still in the box and should be with me by the weekend.





I'll cut the four collapsible fingers off and use the plate with the correct 15-29 internal spline set in it, I'll work out the best fixing method once I have it in my hand. However, after drilling and tapping it should be straightforward enough to just bolt it up to the steering column half of my 48 spline Optimill QR hub.

We're not there yet, but we are well on the way to a cost effective and safe way of converting the beatifully made Optimill quick release hub to a Morgan friendly 15-29 internal spline

Dave.

An additional confirmation of the spline count has just been sent to me by a lady called Karen at Moto Lita, it's possible she was the same lady I first spoke to on the phone who incorrectly informed me my steering shaft was 48 splines, in returning my follow up email perhaps she was looking to correct her earlier mistake?

Either way, Karen has kindly confirmed what I now already know, more specifically she explained all post 2007 traditional chassis four wheel Morgans used a steering shaft that measured 14.94mm and hold exactly 29 splines with no master spline. This is most definitely a Rover size, the 14.94mm shaft with 29 spline specification was used on the 200, 400 & 600 series models and the MGF sportscar, all produced by the Rover Group from the mid 1990's to the early 2000's.

There is also some evidence to suggest the 14.94mm shaft with 29 spline specification first came in to use on the Rover SD1 produced between 1976 and 1986, but this would need fully confirming. It could however point to the Morgan Motor company buying up a supply of new/old stock Rover steering shafts from one of the models referenced above, or perhaps even the venerable old SD1?

This is classic British low volume sports car manufacturing practice, supported by the wasteful over production of parts by the dying UK car industry, small volume manufacturers such as Morgan, TVR and many others made use of a ready supply of cheap new/old stock components that would have been costly for them to produce themselves in the small quantities required.

I appreciate none of the above is news to most of you, and the information I've uncovered on the correct specification of a modern trad steering shaft is largely just a geeky deep dive into answering my own question that spawned this post, but hopefully it will help others in the future?

However, in my typical 'rabbit hole' research fashion it also lead me to Rimmer Brothers who will sell you a brand new/old stock MGF electric power steering column with associated wiring for a very reasonable £336 including the integral electric motor itself.

https://rimmerbros.com/Item--i-500000040

I appreciate there are Morgan specialists already offering EPAS systems, and Morgan even did it themselves, but the aftermarket systems can be costly. I'm left wondering if my latest discovery of the cheap new/old stock MGF power columns would represent the ideal cost-effective starting point to convert a modern Trad chassis Morgan to power steering?

With excellent proven controllers available at reasonable cost from DC Electronics, a quality conversion to speed or strain gauge referenced EPAS could be created using only new parts, but for a very reasonable price!

I think you are right on the money there Dave..... post 2007 48 spline I think was for the Defender Tdci. Although I can't find my invoice for my Morgan boss But I do remember Melvyn saying there was a spline change and he needed my car details to get the correct one. Thinking about it I think it was the Heritage Defenders that returned to an earlier spline count so about 2015? or certainly a different spline configuration anyway. Hey perhaps it the brain addle again and I'm talking rollocks!

I have a Momo shallow quick release on my race Morgan 4/4. I can do a short on it maybe. I stripped off the steering column, took it to a local engineers who cut the old splined section off. They drilled and pinned both the steering shaft and the Momo weld on adaptor and we just welded it up (very carefully).

Jobs good. Works great.

Cheers Andrew, I'm loving your videos by the way, I am now a subscriber

I've already bought the Optimill hub and I want to keep it as it's very nicely made, I just need to convert the column half of the direct to column fit Optimill quick release hub to mate with my 14.94-29 steering column shaft.

Optimill make their quick release hub for the Land Rover Defender so they offer it in two variants to suit that application:

1. A 48 spline for version for a 19mm (a 3/4") shaft

2. A 36 spline vesion designed to fit a shaft diameter of approximately 16mm, or 5/8" in old money

I did ask Optimill if they would be prepared to machine a blank in the Morgan friendly 14.94mm and cut the 29 internal spline in it, but understandably it doesn’t make sense to tool up for a job of one. I have also asked Moto Lita if they would centre drill and spine cut a half blank if I could secure one from Optimill, my thinking being they are already tooled up for the job as their machine shop is already producing these two hub options for post 2007 Trads in the 14.94-29 size I need.

https://www.moto-lita.co.uk/collect...gf_121160=Morgan+Plus+4+Dec+2007+onwards

I've not heard back from Moto Lita on this proposal as yet, but I have my suspicions I'll likely need stick to my plan or harvesting the 14.94-29 internal spline from the MGF MOMO hub that I was able to buy for just £25.00, and using it to convert the steering column half of my lovely 19-48 Optimill quick release hub.


To complete the conversion, I really just need the help of someone with access to a lathe and a pillar drill

Update!

Karen from Moto Lita has offered to have her machine shop drill to 14.94mm and cut the internal 29 spline, all for £50, being already tooled up to to the job they just need an undrilled steering column half from Optimill, so I've asked Optimill if they'd be prepared to sell me a half hub that has yet to be drilled and splined?

In an ideal world this would be the prefferable approach, so I've got my fingers crossed Optimill will sell me the partially machined part?

I hope it comes together for you, it may also help others with the same steering column configuration...........