With some time to think about it, I start to question why the sensor and magnet on the propshaft should have come together. I'd checked the sensor yesterday and it seemed to be still tight. This morning, I thought I'd give the car one further check over before going up to Aldeburgh in it with my son. I was looking to see what could make the propshaft move.
|Taking the rear tunnel top off, I had a look to see if the propshaft could move but it all seemed solid. I then started looking at the differential. It was whilst looking at the rear differential mounts that I spotted this crack in the chassis rail. It's actually a clean break that runs right though this rail. That would explain the very loud noise!|
I decided to put any plans on driving the car today on hold, though it pains me when the weather is this good. Firstly, this is the only rear differential mounting point on the car. Secondly, this horizontal bar also has the upper wishbone mounts fixed to it, at each end. This means that if this bar flexes the rear geometry changes. Thirdly, the black thing behind this bar is the plastic petrol tank and the fixing bolt is only 25mm from the tank. I'm keen that this gap gets no smaller.
Basically, it is game over until I can get this fixed properly. So rather than driving, I'm fixing today :-(
|I realised pretty quickly that access to this chassis rail is going to be a right pain in arse. It's going to need the fuel tank out of the car at the very least. Needless to say, the car wasn't put together with removing the fuel tank in mind. I started by jacking the car up and draining the fuel tank into a couple of 20 litre jerry cans.|
|The large holes in the rear of the bodywork were made to provide acccess to electrics, lights, etc. These are normally covered by my rear difuser. The red tape marks out the extra fibreglass that needs to be removed, to get the tank out. This was a quick job with a rotary tool. I'd recommend the difuser approach to anyone that builds a Fury because it provides a much more rigid fixing for the bodywork. This rear trailing edge would flex about in the airflow otherwise. It also tidies up the rear of the car in my view. You need to be careful it doesn't become an air-brake though!|
|I took out the roll bar out, to make it easier to get to the fuel tank strap fixings. Even so, it is really tough to get to the nuts as they are hidden. I'd also not designed the wiring for the fuel level sensor to be easily undone. It won't be put back this way!|
|With the tank removed, I could get a better look at the damage. This is the chassis rail that has snapped right through. Now I know why it was a bigger bang than a magnet and sensor coming together could have made. It is likely that the welding had weakened the tube and caused a fracture to appear, which then expanded under the repeated stresses into a full break.|
|The break is not as structural to the suspension as I first thought. There are other rails running front/back onto which the suspension points are made. It is the only rear mounting point for the differential though and as such, I'm not sure I'd want to drive the car like this.|
Looking at the design, I'm going to feel a lot happier with some kind of triangulation added to ensure it doesn't happen again. There are also two bolt fixings on the Sierra diff and only one is used on this installation. I'd like to use both.
Booked the car in for the repair work with AB Performance . It will be put on a trailer and towed up to Andy.
Dropped the Fury off with AB Performance .
Took the day off work to go and visit the Team Lotus F1 team up at Hingham in Norfolk. It was a real shame the Fury is currently off the road because there are some fantastic roads through Norfolk and the weather was perfect.
Picked up the Fury from AB Performance . The broken chassis rail has been significantly strengthened with some solid steel bar underneath it. This has beenm drilled through and a much thicker walled tube welded into it, to provide a new stronger support.
Whilst the car is off the road, I've also been contemplating converting my differential from an open diff to a limited slip differential (LSD). This can be done without having to modify any other parts as described here but, it is the best part of £900 to do this work. It should make a big difference in getting the power down though, something I struggle with in the cold and also on track.
|Not enough spare time to put the car back together this weekend but prepared the repaired chassis rail for painting and stuck a new magnet onto the propshaft. ETB Instruments can supply the magnets in packs of four. The repair involves a solid piece of steel being welding onto and along the repair chassis rail. This provides a much more solid mount for the diff bolt.|
I didn't opt to fit an LSD in the end. going to make the most of this summmer and look at it again over winter.
Put the car back together today and made sure things were easier to take apart again if need be. Getting the fuel tank in is a right pain though. Getting access to the strap bolts and nuts is very hard work. Did a short test drive in the afternoon and found the banjo bolt on the exit to the fuel tank was leaking. Replaced the washers and all was well.
Quite a short test run but, car generally feels much quieter and gear shifts are quieter too.
Glorious day and a time to do a proper drive out and check the car over proprely. One of the best drives I've had in years! It might be the enforced abscense but when you get back into a car like this after a long break, you realise just how good the handling is. It really is one of those cars that you wear, rather than sit in. The connection with the car is just amazing.[Previous] [Next]