Marina/MGB axles

[petermads]

I have a just- deceased Marina rear axle with bolt-on wire adaptors. Yes I know expensive but an indulgence and look great. Can anyone tell me definitely that an MGB axle will fit a Marina roadster? There will be permutations with disc or wire wheels, but apart from that, any problems?

[petermads]

Re: Marina/MGB axles

Photo for effect.

[stevejgreen]

Re: Marina/MGB axles

Looks good with wire wheels.
Every option there is to swap the axle with any other will involve a fair bit of work.
For starters, an axle from whichever source apart from Marina will require a change of wheel stud PCD or thread diameter, and that will compromise your wire wheel fitting.
You will need to remove all suspension mountings and replace them with Ford Escort spring hangers to fit.
There is also the issue of brake cylinder sizing and arranging a new handbrake cable.
The diff nose length will change that may mean modifications to the transmission tunnel but certainly the prop shaft.
Finally, as with any second hand part, you may be faced with the refurb costs of your replacemet axle.
None of this is impossible as many including me have fitted a Dolomite Sprint axle that has all these problems.
My installation is documented at http://www.fastmarinamagazine.com/viewtopic.php?f=13&t=2860
But.
Quite possibly the best route, if you are not contemplating engine mods, is to refurbish the Marina axle with a new diffrenetial from a TR7, as Dave (Halifax) did, available from Rimmer Bros being a simple unbolt/boltup swap.
This was done late last year, Have a look at http://www.marlinownersclub.com/forum.php?read=13786&cat=0#n13795 for the parts and cost details
I also took the liberty of posting Dave's pictures at http://www.fastmarinamagazine.com/viewtopic.php?f=13&t=3040&p=29701&hilit=tr7+diff#p 29701

PS
You might have to register for the FastMarinaMagazine forum but the pictures are more detailed than tose available on this forum.

[petermads]

Re: Marina/MGB axles

Steve
Many thanks. Lots to consider!

[djj_engineer]

Re: Marina/MGB axles

I think there may be someone producing bolt on wire wheels for the normal B Axle.

[lil_red_roadster]

Re: Marina/MGB axles

Bear in mind the B axle is narrower than the Marina by several inches (52 vs 48 iirc?)...and I don't just mean the wire-wheel version...which is itself narrower than the standard steel wheel B axle. An MGB axle has been fitted to a Marina...but needed wheel spacers. It is also considerably heavier than the Marina axle, though on a par with the Dolly Sprint unit.

[stevejgreen]

Re: Marina/MGB axles

Jez, you are right about the MGB axles, but also I cannot confirm their widths buy you are in the ball park.
I would be concerned though that with a narrower MGB wired axle that it may not fit on Marina pitched spring hangers. But without the parts and a tape measure to hand I can't really comment.
I would hate to calculate the cost of fitting wire wheels now. I would guess that you would be looking at £250 a corner using second hand parts but new tyres.
I still recon that as long as Rimmers are stocking TR7 parts that it's got to be the cost effective solution to a tired Marina back axle, mostly being un-bolt/bolt-on technology provided you gan get the bearings and hubs off and back on the half shafts.
That is unless like me you come across a Dolomite Sprint axle at a good price.

[petermads]

Re: Marina/MGB axles

Thanks Steve & Jez. Just got the axle back after halfshafts extracted by local friendly classic workshop. The diff was 'lumpy' rather than seized solid. Cause was one of the bolts holding the crownwheel to the diff had come loose and was fouling the casing. Indeed, ALL the bolts were little more than finger tight. As there is blue Hylomar where the brake backplates meet the axle casing, the thing must have been rebuilt perhaps when the car was built, and the builder just clean forgot to do the bolts up properly. I've had the car for over 10 years so I'm surprised it hasn't failed before. Anyway, first impressions are that there's no permanent damage to anything, and that cleaning up the inside of the casing, sorting the bolts and reassembling with new oil seals should do the trick .

[petermads]

Re: Marina/MGB axles

Steve, just to add that the cost of converting to wires with 'kitcar' bolt-on splines and 5 new MWS wheels via the TR shop was about £600 plus tyres a couple of years ago.. Not cheap but part funded by a birthday collection from friends. As and when the car goes I'm sure I'll be able to dispose of them separately quite easily.