The Lotus Grand Tourers

It's not for my diff Bash - I'm building a hybrid Salisbury 4HA/4HU for mine with a torque-biasing Diff. Virtually any ratio available. I'm making enquiries on behalf of a V8 Eclat owner - Eclat body, Excel chassis/running gear.

Marten - I don't know yet. It's just a "how much would it cost" query at the moment. The Salisbury I'm building has a couple of different crownwheel carrier offsets available - not sure about the Toyota diff yet. There may be enough space in the case to offset the bearings to achieve it - that's how the Salisbury works - there's about 0.100" clearance between the case and the bearings on each side so plenty of scope for adjustmant. I could do with a scrap Toyota diff to take some measurements if anyone has one kicking around!

Pete

Saga continues.
Partially dismantled suspension, but only to realise something was hanging up near the front carrier / chassis interface. Closer inspection showed the bolt head from the middle damper weight was too high to exit the chassis pocket.

But the carrier is touching the prop on its underside and prop is resting on the chassis, so I'm struggling to see how diff can be removed with the front carrier, without first getting the prop out of the way !! Hole in the rear of the chassis just doesn't look big enough ( deep enough). Must be missing the obvious, but I can't see it yet. Ideas please?

I think I could just about get at all bolts to separate the diff from the carrier, but surely that's not the only way?

It's too long ago for me to remember .

I saw the gear cutting company today - no-go on the crown wheel and pinion I'm afraid . They said it will be very difficult to find anyone who can do it these days! I'm genuinely amazed - no wonder everything is made in the far east nowadays .

Pete

Look up Harry Martens. (HML vitesse) based in Holland, he had some ‘reversed’ c&p’s made for Citroen Esprit transaxels a couple of years back…..(I used him to try and get a stronger box for my ‘Esprit based V8 Europa’ )

Andy

So, the diff is finally out, but without the front carrier - that's still in the car and from what I can see, needs either the drive shaft out of the way, or maybe I can take the weights off first - more about that another day.

As seen in the photo, the bolt holding the middle damper weight just can not pass the chassis opening. I'd like it out as it has the inevitable crack and having gone this far, I'd like to repair. Has anyone removed the drive shaft from the rear? I'm not yet convinced there's enough clearance where the diff was to allow a full withdrawal. Thoughts or experience appreciated.

At least I can now access a very badly broken down diff bush to replace, so at least all this effort is for a good reason:


I've done a search in the forum for diff removal or cracked front carrier and can not find anything. I'll start new subject specifically on this. I went into this job naively thinking I'd get the diff and carrier out in one lump, with minimal rear suspension dismantling - How wrong was I?

Hi Tony,

The body is currently off the chassis on my car - let me know if you need any pics of what is going on in there from any other angles.

I will have a closer look at mine to see if I have any cracks as well - is there a recommended repair procedure to stop it cracking again that you've seen?

Neil.

Drill a hole at the end of the crack to stop it going any further, v grind either side of the crack and mig weld it up. Did mine about 15 years ago and Ive had the diff out a few times since then and it hasn't come back. I think m t adds a strengthening plate but mines been fine without.

Bash

The body is currently off the chassis on my car - let me know if you need any pics of what is going on in there from any other angles.

Is your car the earlier "horizontal" rear fixing bolts, or the later vertical Neil ?



My car is the later vertical bolts, but it doesn't look much like the parts listings. I certainly can't see the 10mm Tapping plate ( Item 10), nor a bolt that secures any plate. Access inside the rear cross member looks nie on impossible ,so I'm curious if there is a plate welded to the inside of the chassis cross member. That bolt item 11 is an M6 according to parts list, nut I can't see it on my car, and what's the point in tapping a plate M10, then fixing it to the chassis with M6. Any connection is only as strong as it's weakest link. - Confused.
I'm wanting to check / understand the chassis to body fixings at the rear, since I get occasional strange creaking noises from the rear. Sometimes I'll hear it from outside the car on a hot day after a drive, presumably as something cools. The noises may go away with new bushes for the diff mount and a front diff plate without a crack, but access to the underside will never be better than it is right now.

Somewhat belatedly ,I've come across this topic.
viewtopic.php?p=11925&hilit=diff+crack#p11925
The only thing I can add is that I can't see anyway the diff carrier can be removed from the car with two Harmonic damper weights attached (the 3rd has to be removed before the diff can be separated). I would note that both the diff carrier and the rear cross mounting bracket are different between the Non HC and HC cars, so maybe on Non HC cars, it comes out, but I don't believe it does on HC cars.
The work around was to manipulate the plate and the drive shaft, effectively turning them over in the tunnel, so you end up with the prop shaft sitting above what is now an upside down diff carrier. This gives access to the bolt holding the larger (middle when they are all on) damper weight in place though an access hole underneath the tunnel. The weight can then be removed through the hole, then the diff carrier withdrawn from the rear. Fortunately the small front weight can stay put. Good job really as it is the only one of the three that has a Nyloc nut on the inside (not captive).
It should all be worth it though. Its a pretty impressive crack that's developed:

I wouldnt mind betting that when the rust is cleaned off that theres another one from the top edge where the curve is.

Bash

Hi Tony,

Mine is also attached with the vertical bolts (1987) - there is a bolt with a very thin head - see picture below - which holds the nut plate under the cross member. I think that plate can "float" around a bit to ensure it lines up with the body.



Pictures I can take of the chassis won't help with the diff carrier removal - anything useful you can see will be from under the car - it is closed in on top.

Surely just welding the crack won't change much strength-wise and it would be better to add material to beef it up a bit? I can't see any cracks on mine, but....

PS. I have had to resort to using this site with the Microsoft Edge browser to get to see all the pictures (including my own ones) - Google Chrome doesn't show most of them any more.

Neil.