Engine & Gearbox Installation - Part 5 - Propshaft

The final major part of installing the engine and gearbox was to install the propshaft to connect the gearbox to the differential.

Most other builders have used Bailey Morris in St Neots, Cambridgeshire, to manufacture their custom units, and for once I decided to follow the herd.

I downloaded the order form from the Bailey Morris website, completed as many details as I could and emailed the form back with some photos to request a quote.  The guys at Bailey Morris had a couple of further questions for me and asked me to double-check the PCD measurement for the differential flange as clearly the original details I gave them were not something they were expecting (they were correct and when I measured it again I got a completely different answer - but one that did match the expectations of the experts!).

That done, they gave me a quote which I accepted, and all I had to do then was send my transmission yoke off to Bailey Morris so that they could attach it to one end of the propshaft.  I had a confirmation email that my yoke had arrived on Monday and I was amazed to have a new propshaft delivered to my door on the Friday of the same week!

Candidate for the world's shortest propshaft?

While I knew the propshaft was going to be short, when I unboxed it, it was even shorter than I imagined!  It looked like something that would be more at home between the Rover V8 and the Jag IRS of the Mighty Mouse Fiat 500 that was a regular at Santa Pod in the late 80s early 90s...

Of course installation of the propshaft, as with everything on this build, was anything but easy.

Before installation, I greased up the UJs with a lithium-based grease, as per Bailey Morris's instructions, until grease was squeezing out of all the seals on the UJ spiders.

I then slid the transmission yoke fully into the gearbox and tried to get the other end over the locating pin that was protruding from the centre of my differential input flange.  The guys at Bailey Morris did suggest I might have to just cut the end of this pin down slightly to get the prop in.  However, all seemed good, and I could get just get the flange on the propshaft over the end of the pin. But no further, unfortunately...

20mm diameter locating pin on differential input flange

So, not for the last time, I removed the propshaft and proceeded to sand all the paint off the locating pin with some emery paper.  This allowed the pin to seat slightly further into the flange when I reassembled the unit, but I still couldn't get the flange to slide very far onto the pin.

I had to resort to some gentle fettling of the hole in the propshaft flange with a grinding stone in my die grinder to just try and open the hole up fractionally to allow the pin to slide fully home.  This took a few attempts as I didn't want to open it up too much and make the fit too loose, but finally, I managed to get the flange to fully seat onto the pin and the differential input flange.

Propshaft in place

Then it was just a simple matter of getting the fixing bolts in place...

No matter to what position I turned the flange, I could find no orientation at which I could get an M12x35mm bolt into any of the holes (and the bolts were too long to insert from the differential side).

So I removed the prop shaft again; this allowed me to get one bolt in place (with some wiggling) but due to the position of the UJ there was no way I could get bolts into the other two holes from the prop shaft side.

I decided to order some M12 cap head bolts, hoping that the smaller head dimensions would allow for wriggle room to allow me to get the bolts in.  I made the mistake of reinstalling the prop shaft so when the bolts arrived I discovered that I still couldn't get the bolts in with the prop shaft in situ.

So out it came again and with some gentle persuasion from a soft-faced mallet, I managed to get the bolts into all three holes on the flange.  Then hopefully, for the final time, I reinstalled the prop shaft, lining up the bolts with the holes on the differential flange.  For once I had thought ahead and realising that I wasn't going to be able to install a bolt longer than 35mm in length and that the length of exposed thread was going to be quite short, I had ordered some thin Nyloc nuts at the same time as the cap head bolts.  For extra security I used some high strength threadlock on these nuts as well and, as I was unable to get a torque wrench onto the bolt heads, I tightened them up until my face went purple.

Bolts finally installed...

I rotated the propshaft a couple of times to make sure that the bolt heads didn't foul any of the parts of the UJ; it was close but there was clear air, so all good!

Heating & Cooling - Part 1 - Radiator and Fan

Installation of the radiator and cooling fan was a reasonably straightforward job.

I had purchased the AK aluminium radiator when I was up at their open day last September; as they had one in stock it seemed rude not to take it away with me!

I went for a Davies Craig 16-inch unit from Merlin Motorsport for the cooling fan.  This pulls a huge 2120cfm so it should keep my LS7 nice and cool.

The first step was to install the lower radiator mount, which is supplied as part of the AK chassis kit and is fitted with 4No. M8 bolts, washers and nyloc nuts.

Lower radiator mount fitted

There are two pins on the bottom of the radiator which are approximately 10mm in diameter and 20mm in length.  The proper way to sit the radiator onto the lower mount is to purchase some rubber top-hat washers; these slide over the pins and then locate the bottom of the radiator into the two 20mm diameter holes in the lower mount.  Other builders have used a variety of alternative solutions including a couple different diameters of rubber or silicon hose to create the stepped bushing.

I knocked up a couple of top-hat bushes from some 30mm nylon bar which hopefully will do the job.

Two bushes machined from some nylon bar 

Bush in place and keeping radiator from sitting directly onto lower mount

The upper radiator mount is attached to the top of the radiator using 2No. M6 bolts and washers and to the chassis using 2No. M12 bolts and washers.  I needed to clean out the threads in the chassis mounts with an M12X1.75 tap to remove the powder coating before the bolts would thread in easily.  The holes in the top radiator frame also needed some work with a file to remove the excess powder coat.  Initially, I assembled the top mount and radiator to check the fit but did not fully tighten any of the bolts.

The Davies Craig fan comes with four mounting feet that can be installed in several locations around the perimeter; I was hoping that by using the topmost and bottommost locations I could fix the fan to the upper and lower radiator mounts and not have to rely on zip-ties to secure the fan to the radiator.  

Fortunately, this was the case. I started with the holes in the upper radiator mount and drilled two 6mm diameter holes equidistant from the centre of the mount to match the spacing of the fan mounting holes.  I then loosely fitted the fan to the top mount with a couple of M6x25mm cap-head screws and reassembled the radiator and top mount with the fan to locate the bottom holes for the fan in the lower mount. I put some tape on the lower mount before reassembly and used a broken 6mm drill bit to mark the tape at the hole locations.  I then had to take the whole shebang apart again to drill the holes into the lower mount.  These ended up being lower than I had anticipated but still allowed enough space to install the cap-head screws; I might have had a problem with a normal M6 bolt.

I could then fix the fan to the upper and lower radiator mounts using the M6 cap-head screws, washers and some nyloc nuts.  I had to insert the cap-head screws the wrong way around from what I would have preferred to prevent the excess length of the screw from rubbing against the radiator; this meant that I had to tighten up the fan fixings fully before reinstalling the radiator.  Luckily there was enough play in the mounts for this not to be a problem.

Fan fixed to upper and lower radiator mounts

I could then reinstall the radiator, and fully tighten up the bolts securing the upper mount using a dab of blue Loctite for good measure.

A quick check showed that I had some clearance between the fan mounting bolt heads and the radiator so all was good!

Radiator back in and fully secured...

...with the cooling fan snugly sitting behind!

Free air between fan mounting bolts and radiator!

It's starting to look more like a proper car every day!!