My alternative to the clone TKC1044 Sprint gearbox mount.

[Galileo]

Firstly may I add my thanks for the work done here, this really is a fine replacement for a poor re-manufactured unit.

But I would like to add one thing. You need to slot the mounting holes in the cross member to fit the mount. If you do this there is very little left and there would be a big risk of them breaking through when in use. So I will be adding plate to each side of the hole where the mount goes through the cross member to ensure it doesn't break through.

I considered that exact point, but decided that if it was okay for the OEM mount themselves to have slots in them, then from an engineering point of view it would be equally fine if the crossmember was to also have slots in it. Even ignoring this fact, the crossmember is made from 3.5mm steel, and there is 5mm of steel left after elongating the holes. I think that you are adding unnecessary complexity, though of course that is completely your prerogative to do!

The clamping effect of the fastener is enough to keep them from moving, and even if for some reason the fastener had been insufficiently tightened, and bear in mind that I used new bolts and nyloc nuts, then the crossmember opening itself would restrict movement with a clonk to alert the driver of something untoward happening down there.

Checked the work at the weekend and I'm happy to say that after 520 miles of mixed fast road and town driving, nothing has shifted. Actually when I say nothing has shifted, my appreciation of the car certainly has, I see now why Alun said to me when I first joined the forum "...every mile in a Sprint is a pleasure!", because it has now been so, the car is transformed. I realise that seems over the top for just a gearbox mount, but then I'm admittedly a fussy one for noises and rattles, they just grate, and this is probably why I can't remember the last time I broke down, I hear them complain long before they give way!

Edit: Typo

[tom16v]

This is perfect.
Thanks very much.
I spent an afternoon fitting a repro gearbox mount to drive it up and down the road once.
I was so traumatised by the shakes and noise that I undid all my work and put it straight in the bin. I put it back to my old jellyfied mount shimmed up with washers until I happened upon a NOS one on ebay one day and snapped it up. I have no doubt that this will eventually also degrade though and I will be needing your modification.

Cheers

Tom.

[olr159w]

I'm in the process of replacing the gearbox mount using this method and wanted to share a little bit of extra info.

Three things :

1. the Volvo mount is a pretty solid decent looking item and a close match to the OE part. See photos below showing heights and effects of washers. In terms of mounting hole alignment then as described earlier in this thread
2. I bought some subframe mounting washers from Rimmers for another purpose and it turns out they are ideal for the washers described as necessary above. The Rimmers part no is UKC312. These washers are 45mm OD, 13mm ID and about 3mm thick. I will likely use 2 to create a 6mm spacer when I reattach the assembly (Edit - actually ended up wrapping mount in thick plastic "bag" [used part of one of those garden plant protector "tubes"] and then decided I only needed one washer above the gearbox mount. The test was deciding whether the propshaft looked straight with the aid of a laser level)
3. There's no need to use the restrictor plate that clamps up on the underside of the OE part. The Volvo part can be clamped directly although I will add a small washer between mount and nut

rgds

[Busheytrader]

I wanted to say thanks for the information on this forum about the Volvo gearbox mounts.

I have a TR7V8 which shares the same item. After replacing / refurbishing a number of transmission items, including the mount, I thought my LT77 gearbox was about to explode. I was even told by one of the major wedge parts suppliers / workshops that it was my wornout gearbox not the fresh new mount that needed replacing.......

After finding these threads I adapted the Volvo mount to fit and have clocked up 500 miles without incident since. It's handling around 200bhp, the gearbox noise has gone, there's no judder and looked like oem equipment to the MOT tester. I don't know anyone else on the TR7 forum that's done the same thing but there are a number of owners who aren't happy with their noisy transmission after buying the granite mounts supplied in a "made in India" bag.

I now have 2 rock hard redundant gearbox mount paperweights and also a spare gearbox I never needed to source.

I don't know if this Study on the gearbox mounts has been seen on this forum before. It was undertaken in America and published by the TR Drivers Club

http://www.trdrivers.com/tr7_tr8_gearbox_mounts.html

Cheers,

Adam

[Galileo]

It's good to know that others are benefitting from this still.

I'm happy to report that well over 6,000 miles have been completed since this was done, and I had forgotten completely about it!

[tony g]

Top find this was. Mines been on about 1000 miles and as you say mostly forgotten about

Tony

It's good to know that others are benefitting from this still.

I'm happy to report that well over 6,000 miles have been completed since this was done, and I had forgotten completely about it!

[GTS290N]

Just ordered one, was under my 1850 and the tkc1044 mount is soaked in oil and splitting. I'll wrap this one in a plastic bag when fitting, as someone else did, can't remember who.

[olr159w]

Um, me, 4 posts above.

[GTS290N]

Um, me, 4 posts above.

It's an age thing.

[olr159w]

Its OK. I know, very familiar with the effects.................!

[GTS290N]

DSC_0006

Removed the old mount, new one fitted, fashioned a plastic bag 'umbrella' above the mountthat will hopefully prevent oil collecting in the mount.
Thanks to Galileo and olr159w for their posts.

Question - how do I know I've fitted enough shims? I can't get enough access for a laser level or anything. I reckoned 3mm was enough, but how can I tell? I'm guessing if the box is at an angle it's going to ruin the spigot bush?

[soe8m]

No it should be box+engine at the right angle. As long the box has all it's bolts and nuts tight to the engine the spigot bearing is not a player in the game.

Jeroen.

[Galileo]

As I did not have the OEM dimensions of the TKC1044 I measured the difference in height between my existing mount and the new one as 9mm, but of course the existing mount was very much past its sell by date. I used 6mm in the end, I doubt you would go far wrong with that figure.

What you are trying to do is keep the propshaft in alignment with the centre line of gearbox output shaft, though in reality I very much doubt that +/- 3mm makes that much of a difference however if out too much it would cause accelerated wear of the universal joint.

[Carledo]

Actually, having the crank/gearbox mainshaft and the front half of the prop in perfect alignment is NOT what you want, apparently, it leads to odd harmonics that create judders and resonances in the driveline, so my propshaft specialist informs me anyway!

Thinking about it, the angle is only approximate at best, a saggy engine mount or two will give a couple of degrees variation as well.

I've just fitted the Volvo/Febi mount to Mahesh's car without shim washers at all and it seems fine. Will be able to judge more exactly when his rebuilt and rebalanced prop is back in place, rather than the unknown one we borrowed off Alun (but thanks for baling us out at the 11th hour Alun!)

Steve

[Galileo]

Did you employ your best adenoidal nasal twang starting with 'Actually' Steve?! Quite correct though, the prop should not be in perfect alignment otherwise the torque stresses are not spread over the entire UJ bearing surfaces, so an offset is always desirable.

Maybe you don't need the shims, maybe you do, I was keeping everything approximately in the alignment that Triumph employed. The mount is far back with the pivot point being far forward, so any change in height will be exaggerated at the very front of the engine. Engine mounts are hardly a technical mount being just a slab of rubber so doubt it would stress them much.