Sunday 18 January 2009

Reverse update..

Well it turns out the reverse gear selects with no problem at all, if you look in the right gate position!! I was trying to select it in right and back behind 5th when in fact its left and forward next to first!! Hey ho, you live an learn.

I did however find something which may be more concerning, upon removal of the magnetic drain plug there were a couple of teeth tips or bits of synchro clung on. I'm not sure what exactly they are, if they are left from a previous failure or what implications this could have.


So I have taken the decision to get the box rebuilt, I think its worth the extra cash. I'm hoping they wont find anything terribly amiss inside leading to an expensive bill!

I just need to sort out the logistics of getting the box over to the re builders (once I've sorted out just who is getting the job) and whether to paint all the bits first or wait until it comes back.

Moving forwards....and backwards....

Literally! I took a step closer to getting this thing moving last week.

Following a discussion on the CRC I became aware that there were more options open to me with regards to a gearbox. I had always thought that the only way to go was with a new Tremec TKO 600 box, I always dismissed using a 2nd hand box as too fiddly to get working and too risky for reliability. However I have been enlightened as to the benefits of fitting a used Getrag box.

The first concern was ease of fitting. Well BAE are developing a bespoke bell housing for the 302 to mate with the Getrag box so thats that issue sorted.

My next issue was reliability. Well I am now informed that many people are driving around with more powerful engines than mine and are quite happy with a Getrag fitted. Most with only the front and rear seals having been replaced before fitting so that looks like not being an issue.

With this in mind I set out to find a suitable Getrag box from either a BMW or JAG, the JAG being the preferred box due to the gear ratios.

I had been advised via the CRC website that the ratios are as follows:


More on ratios later.

I was contacted by Pete in Bristol (fellow CRC member) who offered a box for sale and after an interesting morning discussing all things, and checking the gearbox apperaed OK, I drove aware with said box acquired.


All forward gears select OK but it currently wont lock into reverse, now some of that might be down to it having no oil in it and also that I don't fully know where reverse should be!

Before doing anything to the box I decided to re-visit ratios to make sure I was happy. I managed to find a copy of the Jag service manual for the 3.6 XJS from which I was informed the gearbox had originally been taken

I found that the ratios were slightly different to those I had been advised previously, ratios and speeds in red are for the Getrag 270 box which I believe this to be, unfortunately Getrag helpfully do not appear to mark this on the box anywhere!


(double click on image to see readable version!)

So plotting the various box options together I can see very little difference and hopefully little difference to driveability.


The box is in need of some work so my first job was to remove the bell housing. Four nuts undone and off it came.


Next up I will remove the metal work for stripping and painting, clean the box fully and then consider if I need to paint the gearbox casing.

First job though is to get some oil in it to soak things a bit. Then I need to replace the front and rear seals but Ill only do that once its soaked and I've managed to get reverse operational otherwise its a pro rebuild at £250 plus!

Thursday 1 January 2009

Happy New Year

Well that's 2008 out of the way.

I'd be lying if I said that things had gone according to plan and I'd achieved what I wanted to on this build. By this stage I had hoped to have the engine/gearbox set up and mounted and most of the remaining chassis components in. But as usual life dealt another duff hand of cards and we've had to make the best of what we had with no progress on the car since June.

Hopefully, although I am far from confident, 2009 may be a bit better and I can take the closed sign down. In reality I think its staying up for a while longer yet.

Hope you had a good New Year, we had a laugh and my experiment in firework displays went off really well, if I can get a video done Ill post it up.

Thanks for watching..