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The Easter weekend has seen a bit of progress. I raised the rear suspension up to balance out the increase in the front rideheight. This involved clearancing the side of the IRS frame to allow the springplates more clearance and then turning the springplates by a notch. The rear now sits 1 1/2 inches higher than the front. With the 16 inch wheels it almost looks like the rideheight is stock.

The clearancing of the frame allows more travel for the rear suspension, previously the springplate would have hit the frame on full rebound, causing possible wheel hop. This has now been cured.

Another thing that I've been doing this weekend is rebuilding the Porsche 5 speed gearbox that I have. Originally I was going to take this in to have it rebuilt but having run out of decent sized jobs to do on the Ghia, I thought I'd have a go myself.

The gearbox was supplied to me in an 'unknown' condition - I bought it from a Porsche dismantlers / spares supplier when I was back in the UK. The only thing that was known about the box was that it was beleived that the synchro's needed replacing on 1st and 2nd, so they also supplied me with all the stuff needed to fix it.

After removing the nosecone I discovered that to strip it down any further I needed to remove the nut on the end of the shaft that holds the 5th / reverse synchro mechanism in place. OK - no prob - Just exactly where are those oversize sockets I thought I had?????? After a not so successfull search for a 36mm socket I decide that I will tackle it the 'old fashioned way'

After half an hour with a club hammer, cold chisel and a blow torch the thing still isnt shifting. Time to revert to Plan B (Go out and buy a 36mm socket). After scouring the local DIY stores, motor factors and 'cheap as chips' shops I discover that the largest single socket anyone supplies is 32mm. Bhah!!?! So I decide to buy a complete set of sockets as I'm sure they will come in handy again one day (mnnnnnn likely story). $160 later I can now undo anything (provided it's no larger than 50mm).

Great. Now back on with getting the nut undone...

Turning the nut is only one half of the problem (now solved with $160 36mm socket) - Holding the rotating shaft is a different story altogether!! I try the trusted 'jam in a screwdriver' method - The nut won't budge (the gearbox simply moves round the bench) - I do the same thing with the gearbox on the floor with me standing on it - nope - still not moving.

Then I decide that I need something more substantial to hold the shaft and provide me with some leverage. I find a chain wrench which I use to hold the end of the shaft - Things look promising. That is until I disciver that what I thought was the nut coming undone is simply the chain wrench being mangled. Phah!!?!! Looks like it's back to the drawing board.

The tools for doing this job properly are quite simple to make - that is if you have a spare 915 gearbox - all you do is weld a handle onto the sliding ring that the synchro mounts to and use it as a giant ring spanner to hold the shaft with. Unfortunately I have neither a spare 915 box nor anyone to borrow the correct tool from. I tried engaging forward and reverse gears at the same time to lock out the shafts (seemed like a logical thing to do to me) but due to the helix of the gears - without the case to retain it in position the reverse gear simply kept popping out of mesh.

I figure that now I have a socket, I need to crank up the compressor and get out the impact driver and that'll take care of things. As usual - nothing is a simple as it seems. The compressor still has a UK style plug on it, I take care of that small issue. Then I check the oil and get it running to build up some pressure. I oil up the gun and check it over before finding an adaptor for the socket (not an ideal thing to use with an impact wrench). I connect up the air hose and.........

I decide that Google is my friend and that hopefully I should be able to find the answer to my problems as I'm sure someone has felt this pain before. The bigest question for me is a simple one - Is it a right or left handed thread????????
Try as I might I can find no info on rebuilding a 915 box - Well I found one person who had done it but there was no mention of the dreaded nut. Damn. It appears that most Porsche owners don't like getting thier hands dirty.

Ok. What's next?? Ahhhhh........ The bench vice!!!!!

I lift the box back up onto the bench and put the end of the shaft in the vice. (Just thought I'd mention that the end of the shaft is hardened and so isn't getting damaged by all of this). I get my new $160 socket in place and the giant T-bar that came with the giant socket set and put some effort into cracking the nut off. At first the only cracking I can hear is my joints, then there's some movement - excellent!!! it's finally coming loose.

NOT!!!!!!!

I hear some more cracking - the top of the bench splits.

I decide that another trip to the local DIY store is in order to see if I can buy a more substantial chain wrench. After a little searching I find a massive set of adjustable 'water pump' pliers. $26 later and I'm ready for round 5.

I get home and get the gearbox back on the floor. I apply some more heat to the nut - just for good measure - I then manage to get the water pump pliers in position so that I can stand on them with one foot and the socket and T-bar in position so that I can stand on them with the other foot. After a little jumping about it finally comes free.

WooHoo - There's cellebration!!! (I have a well deserved cup of tea!).

With the nut removed I can lift off the gearbox casing to reveal the inner workings and after a little inspection the worn synchro appears to be more like a shredded synchro. No probs - I have all the parts.

I strip down the selectors and gears, and remove the worn dog rings (when I say 'worn' I actually mean obliterated) and mangled synchro rings. The dog gears need a little heat and a cold chisel to remove but come off relatively easy.

I put first and second gears in the freezer and whilst they are shrinking I give everything a good clean in degreaser and take check of the situation.

After applying a little heat to the dog gears they can be 'pressed' onto the first and second gears. These are then reassembled with the new synchro rings ready to be put back in the gearbox.

All is good, apart from the wrecked spider that supports the sliding gear - the three teeth that the sliding gear locate on are completely missing on the 1st gear side. My guess is that it must have been one huge launch followed by a huge bang. I will have to order one of these before I can finish reassembling the box.

I'll order this next week and hopefully get the box back together next weekend (If I get the part in time).

I'm also going to write a tech article on rebuilding the box as there is not too much about on rebuilding these - Maybe I can help someone avoid several hours of torment trying to undo one simple nut....