Oil Temperature Sender

My Acewell digital dash has two inputs for temperature senders.  One is mounted in the thermostat housing and measures the coolant temperature.  For a while now, I've wanted to use the spare input to measure the oil temperature.

First I got hold of a spare 1/8" NPT temperature sender that is compatible with the Acewell unit.  The only place that this can be fitted is in the Raceline sump plug.  I called Raceline and they kindly informed me that the sump plug is 1/2" BSP, whereas the front plug that is used to access the gauze filter, is slightly larger at 3/4" BSP.

So, to get the sender to fit in the sump plug I needed a 1/2" BSP male to 1/8" NPT female adapter.  Thankfully, eBay came to the rescue again with a nice anodised blue item.  Thought I'd get blue to replace the blue Raceline sump plug.

First job was to fit the sender in the adapter.  As the NPT thread is a tapered one I used just a couple of turns of PTFE tape to lubricate the threads.  Then I swapped the Acewell plug for a waterproof 2-way AMP plug.  The white Acewell connector was used at the other end to connect into the short wiring harness that plugs into the back of the digital dash.  Some spiral wrap was added to give some protection to the wires.

The best metric copper crush washer would have been 21mm, but the nearest commonly available is 22mm.  This was slightly too large and leaked.  In part because the head of the adapter is not very wide, so the crush washer needs to fit very closely to the threaded part.  In the end I got hold of a 1/2" BSP washer, normally used for sealing air lines and tools I believe.  This seems to be holding up well so far.

I'm conscious that the end of the sender, along with the associated wiring, is a little vulnerable hanging out the side of the sump.  I'm not planning on putting any additional protection on just yet, as one of my next job will be to fit a sump guard.  This can be made in such a way to provide some cover for the sender and wiring.

I've been out twice now: once at around 5oC ambient air temperature and once at around 15oC.  Both times the oil temperature got to only the high 70's oC.  It did fall a little when moving at speed and did rise a little when at rest, so there is certainly a degree of cooling of the sender, or even sump, due to airflow under the car.  I think the oil temperature is not rising further due to the large volume of oil in the Raceline sump (5 litres) plus the large surface area, including cooling/strengthening fins.

It will be interesting to see what temperature the oil gets up to on a quick run on a hot summer's day.  I think once the sump guard is fitted, this will allow the sump to run a little warmer.  Also, the sender is shielded a little inside the cavity of the adapter so this might knock a few degrees Celsius of the reading.

FIA Kill Switch

I'd been meaning to fit a battery isolator for a while.  Partly as a safety feature for when the car is stored in the garage and partly in preparation for possibly taking part in formal motorsport events, e.g. sprints.

There are simple isolators available that just cut the positive connection to the battery.  They achieve the goal of isolating the battery, but if turned off whilst the engine is running, will very likely kill the circuit in the alternator, as the load has nowhere to go.  Also, if the ignition coil/ECU is not isolated from the alternator, it is possible for the engine to continue running even after isolating the battery.

The solution to both of these issue is to use the more advanced model of isolator switch.  As can be seen below, this not only breaks the supply to the coil/ECU, but also dumps the alternator load to a resistor for the short period after the isolation switch is activated and before the engine ceases to rotate.

The main challenges to fitting the switch to an Avon with the bodywork fitted was finding a suitable location for the switch as well as routing the wiring.  I had some bespoke cables made up by a seller on eBay.  These were 170 amp rated and had the appropriately sized ring connectors fitted on each end.

I decided to locate the kill switch in a hole that was used for a side mirror before I fitted the cage.  The one on the other side of the car still has as blanking bung.  This location for the switch should also comply with the MSA regulations, i.e. it can be activated by the driver whilst strapped in to the car, as well as a marshal from the outside of the car.

IVA Re-Test Modifications

IVA re-test booked for 22nd February.  Modifications to address the fail items have now completed.

1.  Exhaust clamp rotated around towards the sill of the car.  Also cut of the excess thread that was showing through the clamp.

2.  Minor wiring change behind the fog light switch so that the switch light only comes on with the fog light iteself.

3.  Brake lining wear inspection holes (13mm) drilled in brake back plates.  New bungs were inserted.  

There aren't too many options for where to drill.  Some of the flat areas are indented for the purpose of holding the shoes in position.  Had to use one of the few spare recesses.

It was quite fortunate that I spent a bit of time working under the rear of the car as I spotted a problem.  I had installed the rear dampers with the adjustment wheel facing up/outwards.  This was okay during the build with the chassis up on axle stands and the suspension hanging.  However, once the car was on the ground and with the suspension moving through its full travel this adjustment wheel was fouling slightly on the horizontal tube of the upper wishbone.  It was lucky I spotted this before any permanent damage was done.

The fix was quite straightforward.  Unbolt the damper top and bottom, spin through 180 degrees so that the adjustment wheel faces downwards/inwards and re-install the bolts.

Front Lighting

The IVA test requires that the front indicators are no more than 400mm from the outside edges of the car.  On the Avon this would be measured in from the rear wheel arches (being the widest part of the car).  The rear arches are 1750mm in width so the indicators need to be no less than 950mm (1750 - 800) between their outside edges.  As with most sevens the indicators needed extending on stalks.

I found a plastic waste overflow pipe at B&Q which is the perfect fit to hold the motorcycle indicator units.

To create a fixing to the nose cone of the car I used a 22mm copper pipe blanking cap with a M8 bolt.  An 8mm bolt was used as this is the same as the indicator unit bolt.  The centre of the bolt was drilled out to allow the wires to pass through.  A length of rubber sleeve was used inside the bolt to prevent chafing on the edge of the hole.

As well as using glue a couple of 3.2mm rivets were used to lock the bolt in place and prevent it spinning when tightening the nut.  Finally, prior to fitting, a quick coat of black paint was used to cover the copper and rivets.

To allow more clearance on the cycle wings I've changed from the 5 3/4"  light units to the smaller 4" Dominator motorcycle units.  Being smaller they should reduce drag (a little) and boost the top speed (a little).

The wires needed extending and protective sleeving added.  The colour scheme for the wires was very bizarre.  I had to trace each one to the bulb holders to work out what was going on.  After the bullet connectors were attached I labelled each one to prevent future confusion.

Being a motorcycle light the Dominator has a flat beam pattern, with no kick-up to the left.  This is fine for the IVA test, but to help it pass the MoT the light unit is best rotated a few degrees to give the required kick-up.  To do this a second locating cut-out was filed, to the right of the original one.  This causes the whole light unit to be rotated anti-clockwise when viewed from the front of the car.

Front indicators and headlights mounted and wire in.  I'll replace the bullet connectors with soldered connections after the IVA test.  I've ordered some proper two pin connectors from Ebay for the front indicators.  This will make it easier to detach prior to removing the nose cone.

I had some black card handy in the garage so I thought I'd use it to check the beam patterns.  Here is the dipped beam.  Hot spot in the centre and kick-up to the left.  Hopefully good enough to please Mr (or Mrs) MoT tester.

And here is the full beam.

These are small light units and are mounted quite low.  As such their beam will be masked partly by the front cycle wings.  This should not be too much of an inconvenience as they will really only be used to get home around dusk.  I don't plan to be making too many long distance trips at night.

Rear Lighting

All fitted, wired up and tested.

Some of the wiring could be attached to the chassis tubes, but inside the wheel arches there is nothing to attach the wires to.  Some Grip Fill was used to glue clips to the inside of the wheel arches and then cable ties could be used.  Sprial wrap was then added to all wires to prevent chafing, particularly where the wires pass through the fibreglass.

As the fog light needs to be vertical for the IVA test I used one of Tiger's fibreglass 'wedges'.  I didn't need to use them on the rear light clusters as my light units are tapered at the back.  To mount the wedge I made up a small bracket.  I made sure the holes in the bodywork are the same spacing as on the fog light until, so in theory I can attach later without the 'wedge'.

Cycle Wings

After the bonnet the job I was least looking forward to was fitting the cycle wings.  It did indeed turn out to be quite involved.

First off I needed to clear the threads in the front uprights - these were rusty and also had some paint in them.  I hadn't realised when renewing the uprights that these threaded holes would be needed.  A second hand 8mm tap from a local tool shop did the job easily.

Spacer tubes need to be cut to mount the cycle wing vertical arms the correct distance from the tyres.  This is a bit of trial and error and I found it easiest to use washers to calculate the length prior to cutting the tubes.

With the stays mounted in the correct position I could start to fit the cycle wings themselves.  They don't just bolt on unfortunately.  The horizontal arms of the stays need to be bent up into the curvature of the cycle wings.  To work out how far to bend them I tried spacers of different thickness.  A couple of pencil rubbers turned out to be perfect for the job.

Then the stays were bent in the vice, ensuring that the upper part remained parallel with the tyre.  Due to the bending of the stays some of the powder coating flaked off.  Some Hammerite was applied to prevent rusting.

The cycle wings were then trial fitted using an axle stand as a height reference.  The current IVA manual states that the cycle wings must extend at least 50 degrees to the rear and 30 degrees to the front.  The rear was nearly 90 degrees so that was okay.  The front was harder to measure.  In the end the geometry of the wheel came to the rescue.  There are 12 spokes.  360 degrees divided by 12 equals 30 degrees per spoke.  With one spoke vertical I could easily determine that I had about 45 degrees coverage to the front.

A length of bicycle inner tube (700c x 23) was pulled over the horizontal arms to protect the fibreglass from the metal edges.  Holes were drilled in the cycle wings and stays and then dome head bolts used to secure them together.

19mm holes were drilled to accommodate the LED side repeaters.  I had to be careful here as it is quite close to the edge and I didn't want to split the cycle wing.  The repeaters are mounted by inserting the rubber collar into the hole and then pushing the light through, making sure the 'TOP" marking was uppermost.  Due to the curvature of the cycle wing shoulder the rubber did not want to sit fully flat with the (curved) surface.  A little persuasion from Mr Super Glue did the trick.

Finally, the wiring for the side repeaters was extended to reach the inside of the car.  This was cabled tied to the cycle wings stays and under the cycle wings cable tie mounts were attached using Grip Fill.  Before fitting the side repeaters I tested them on the car battery.  They are reassuringly bright.  One oddity is that the black lead is not negative, but positive!  White is negative.

In the end I am quite pleased with result, but the cycle wings are quite a lot of effort from start to finish.

Wiring Check Out

Now that the wiring is complete (standard Tiger loom, not Webcon Alpha loom) I decided to give it a little test.  It is much easier to fix errors now, before the body is on.  There were just a few gremlins to fix, like the relays in the wrong sockets and the low and high beam wires mixed up on the steering column switch.  Once corrected everything seems to be working correctly.

Here are the rear lights all switched on.  The camera on the phone has not coped too well though.

Once satisfied that the loom was all correctly wired in it was time to try the digital dash again.  Here all the 'tell tales' are illuminated.  Not something that you'd want to see while driving along!

There is just the reverse switch to wire into the digital dash.  The dash supports a reverse gear logo ('R') as well as 'calculated' gears.  To light the 'R' on the display requires a connection to ground.  However, the output of the reverse light switch on the gearbox is +12v, so I need to use a relay.

Once this reverse gear indicator is working I'll tidy up the Tiger loom and move on to the Webcon Alpha loom.

Polo Radiator Fitted

Some simple brackets made up from 5mm steel strip.  B&Q had exactly the right piece of steel available from which to cut these.  The brackets were given a quick couple of coats of Hammerite.

Lightweight (tinfoil and plastic) Polo radiator fitted and fan mounted.  I decided to go for a 'pull' type fan in the end. This leaves the front of the radiator free for fitting an oil cooler later - no plans at the moment though.

The 12 inch fan fits in very nicely behind the radiator.

The radiator was mounted at angle for two reasons.  The first, as I don't yet have the bodyshell on I don't know how much space I have to work with, so erred on the safe side.  Second, if mounted vertically both the pipe openings clash with other things (steering rack and upper chassis rail).

The fan wiring will be connected once the wiring loom in the engine bay is properly routed and mounted.