Anybody know if the mounting points/brackets used to put an S type on a rotisserie are the same as the MkII?

 

Tell us where they are on the Mark 2 ! Seriously, I would think the front identical, but at the rear, who knows because the S-type has the independent rear suspension on a subframe, whereas the Mark 2 has the normal axle with leaf springs, and no subframe.

 

Cass will hopefully respond. He used a rotisserie to restore his S Type. I've seen the front & rear bumper mounts used but that might not be the safest way. (Bare body) ~ Mk2 rear is different.

 

The rotisserie has to be mounted in such a way that the cars shell can rotate around its centre of mass or axis. Set too high and the you cannot turn the car upside down, set to low and it will be top heavy and very dangerous and difficult to control. I have posted some photos of my S Type on the rotisserie to give you an idea how I set mine up.
For the front I made up a bracket which was bolted on to the front bumper irons which in turn were still bolted to the car. The bracket allowed the front of the car to drop slightly but still allowed full rotation of the chassis. There was about two inches between the lowest point and the floor. I do not have any photos of the car completely upside down but it would go all the way around. The wooden block was just to stabilize the chassis on the rotisserie in the position I needed it to paint the underside.

On the back it is slightly different as the centre line is just below the boot line and there is nothing to bolt the bracket to so I had to drill two holes in the back of the chassis just below the bumper line and I then bolted the bracket to the back of the car. I was tempted to bolt it to the bumper mount holes but I thought they were to small for the amount of weight the bolts were going to have to hold. The holes I drilled are still on my car as ideally you would want to weld them up when you remove the rotisserie but as I did all my paint work whilst the car was on the rotisserie I did not want to do damage the new paint work so I just left them and inserted rubber bungs in them after I had finished. They are hidden by the bumper anyway and I might want to use them again in the future. You never know.

Hope these help. If you want more info you have my email address and I can send you more photos.



White primer being applied showing front mounting bracket.

Rear mounting bracket attached below bumper line.

Rear mounting bracket side on.

Front mounting bracket attached to bumper irons from the top.

Front mounting bracket attached to bumper irons from the bottom.

Rear mounting bracket viewed from the bottom.

 

Thanks Rob. I thought you would have pics & method. Your front & rear is exactly as I have seen. Only difference is while rear line identical they had left the rear rubber bumper mounts/same as engine mounts in place & bolted to their centre hole. Your rear mounting is more robust.

 

I would advise against using the rubber bumper mounts as a securing point as these are not strong enough to take the weight of the car. These are strong enough to hold a bumper on but not a ton of chassis to the rotisserie. I had thought about the mounts at first and if you look at the picture of my rear bar you can see a slot I had cut to connect it up this way but as soon as I started to put the weight on I saw the mounts deform and the rubber was trying to delaminate from the metal as has happened to me with an engine mount. (Engine moved forward and took the back of the radiator out with the fan) Sat upright it was OK as the bar sits below the rear valance and the chassis was resting on the bar but as soon as you rotate it on to its side or upside down the rubber mounts will come under a lot of strain.
To put my chassis on to the rotisserie I used an engine crane to lift first the front then the back whilst I slid the rotisserie supports into place. This is a picture of the chassis being lifted off the rotisserie and onto the front subframe assembly using the engine crane.

 

Thanks Rob
That's a great help

 

I agree with you. The guys I saw just got lucky. I guess one could bolt direct to the bumper mount studs but you have done it. It's not going to break with your robust mounting method.

 

Glyn I had thought of drilling straight through the centre of the bumper mount so the hole would be hidden but I think the chassis leg comes up behind the mount so I had to move it to one side so I could put a plate on the inside to spread the load.

 

What I’m going to ask may be more important for Mk2s than S-types, as S-types have a lot more substantial underframe structure. At what stage in restoration can you put the car on a rotisserie and what sort of temporary frame or stiffening do you weld into the car first?

There are a lot of restored Mk2s with hopeless or less than perfect door gaps. I’ve even seen a couple where the waistline of the front door is half an inch below the waistline of the B-post. A corroded Mk2 is not very stiff. With my car, I’m working on the sills, sill to post connections, rear spring boxes all with the car upright. I have the doors in place. I adjust the support under the car to keep all the underbody aligned and maintain door gaps as good as I can.

It would be easier for me to work on the underside with the car on a rotisserie. But I’d have to make a major framework inside the car to fix everything square. Doing as I am, by the time I’ve got the car to a state in which I could put it on a rotisserie, I’m not sure if it will be worth the effort or investment.

Have I got something wrong?

 

The MK2 is pretty strong, I would put it on a rotisserie once the sills and chassis rails are in good condition and keep the doors fitted at all times so you can be sure that the gaps are ok.

I used a rotisserie from these people and its been great with their loading tool to get the car onto it:

https://www.rolloverjigs.com/

If ypou have a lot of welding/ bodywork to do then a rotisserie is invaluable.

 

The S Type has a substantially strengthened rear over the Mk2. The "Chassis" rails are extended over the rear axle & terminated at the bumper mounts & has a double skinned boot floor other than the centralised spare wheel well. Double skinned & fluted for strength section over the rear exle to mount the IRS bridge piece. The S type also has 3 element/part sills & box members on the sides of the boot inside of the dual fuel tank pods. Hence it's weight gain. The real strength in a Mk2 ends at the semi elliptic spring mounts & the 2 part side sills.

The S Type is an altogether more stiff structure.

 

Although not as comprehensive as the S-Type the MK2 "chassis" doesn't stop at the rear springs, there is a box section that extends over the axle and then a member which runs from the rear bumper mounting towards this although this relies upon the panels around it for strength to interface the two.

The MK1 and MK2 were Jaguars first monocoque cars and as such they are massively over engineered. On the two I have done they have been fine on a rotisserie even when the area around the bumper mounting has been in a very poor state.

 

Yes I agree they are over engineered. I was just parroting Cyril Crouch & James Taylor from various books on developing the S type with the help of Pressed Steel. Cass pics above clearly show what I'm referencing.

S Type's 3 part sill clearly shown here. Middle or centre sill piece shown with holes punched into it.

Peace ~ I'm certainly not trying to argue. I'm just trying to help Peter maintain his door gaps. You have far more hands on experience with the Mk2 than I have. I have researched the S Type backwards because that's what I restored ground up.


Picture courtesy of Orlando.

 

I think putting the car on the Rotisserie and how much reinforcement you add, depends on how bad the car is rusting away. My S Type was pretty solid as the sills had already been done and the major chassis legs that run the length of the car were solid. Being a Monocoque body means there is still a lot of strength in the structure and leaving the doors in place is a good idea to keep the car straight even when doing the sills. As the car is not like a soft top where all the strength lies in the chassis legs and sills I think you can mount the Mk2 or S type on the rotisserie as soon as you have the sill structures welded in place. If you wanted to weld the sills in place whilst the car is upside down you can mount the car in the rotisserie and add two long lengths of steel welded or bolted along the side of the chassis legs attached at either end to the Rotisserie so the rotation weight is taken up by these lengths rather than the chassis of the car but it would be expensive buying the metal you would require.
Welding upside down is a real pain as I have just done some welding repairs in a wheel arch but I would think that as soon as you have tack welded the sills in place they would then have enough strength to be able to spin the car over with the doors in place and the weld could be completed with the car upside down.

 

Thank you all for your good advice. It’s very much appreciated. I very much admire the work that you and others in this forum have done on your S-types and Mk2s.

I didn’t buy my Mk2 to restore – I’d have found a better one. It’s one that’s been in my family since 1964 so it’s a case of sentiment over logic. To make things worse, it has suffered twice from some ‘not too good’ professional restorers. What I’ve done is on the right side of the car: repaired the right side inner sill, added an S-type inspired intermediate sill, repaired and improved the sill to post connections, and replaced the spring hanger sections of the chassis rail. At this stage, the right side doors look a decent fit. I’ve left enough not welded to make some more adjustment should things change following work on the other side of the car. Since I did all the above more than a quarter of a century ago (before life got in the way), the Practical Classics Mk2 work in the 1980s was my main source of information. Time may have passed, but I absolutely agree that working on the underside with the car upright is awful.

Following your comments, my plan is to do similar work on the left side. After that, I’ll do some tests on stiffness by jacking at various points. If all looks good, the car can then go on to a rotisserie.

The Mk2 floor pan is very strong, but that doesn’t necessarily make it stiff. After all, not matter how strong it is, it’s still a reinforced sheet. I suspect that may be why Jaguar added the intermediate sills in the S-type and made huge changes for the Mk10 and XJ. The Mk2 relies on the sill to door post connections that I'd guess were details designed by the Pressed Steel Company more for easy fabrication than structural performance. By any standard, they are rather feeble, highly stressed and inclined to corrosion.

 

Yes ~ I think one needs to differentiate between strong & stiff. I was surprised at how stiff my corrosion free S Type shell was considering age. Obviously not modern vehicle stiff.

 

Hi Glyn, apologies, no intention to argue either, just providing my 2 pence worth based on what I have found. Care needs to be taken to ensure that nothing moves and I found with mine repairing the sills and the chassis rails was enough to make it strong.

When I restored my S-Type I was impressed with the middle sill and considered adding it to the MK2's I have done but always shyed away as they seem ok without it and it does add cost.

The main thing is to make sure that the shell is strong enough to put on the rotisserie and I would avoid any welding that might alter/lock in the door gaps. The rotiseriee is great for repairing things like the inner and outer front wings, the rear arches and bits of the floor. I would only set the door gaps with the car on the floor and its wheels.

As an aside I too have read the bit about the S-Type having a double skinned boot floor but I don''t recall this being the case but don't have one to look at. Any idea which bit is double skinned?

 

Understood and no problem whatsoever. We are all here to try & help one another.

I don't know exactly where it is double skinned. Certainly not the spare wheel well. I took the comment on face value from Crouch.

My car had a completely rust free shell having spent it's entire life in SA's dry interior. Did not even have the little rust spot on the rear door skins where Jaguar mounts that little felt pad where the vertical window channel touches the skin and usually remains damp.

As a result never having to cut any rear bodywork I could never validate the claim. Only rear repair was knocking some minor dents out of the spare wheel well. I can't see where it's double skinned. It's certainly solid if you tap on it.

 

I have just looked through my photos taken during my rebuild and specifically at the blasters and cannot see any double skinning on the rear end.
The only double skinning on the back of the car is between the outer rear wing and the inner rear wing which forms the inner wheel arch and the outer wing This continues along to where the fuel tanks sit and strengthens this area so the rear bumper mounts are bolted through the outer wing and on to the inner panel.
You can see from these photos that the strengthening indents in the panel across the rear subframe mounting area are the same from under and as above. I would say that the metal in this area is a lot thicker than say the boot spare wheel well but it is only single skinned.
Don't understand where Crouch got the idea it was double skinned.