Fuel Tank Sender Update

Fuel Sender Gasket

When re-fitting the fuel sender, we utilised a custom TPU gasket. By adjusting the infill density and wall thickness during the printing process, we were able to fine-tune the gasket's compressibility and seal quality 

*Update* - The TPU gasket looks to be a little on the firm side and petrol is leaking from the sender. Sourced the correct rubber and cork alternative to replace.

Fuel Sender Float

For the floats we tried a couple of different wall thicknesses and left them to soak in petrol for a week or so to see if they held up. The good news was they all floated but not as buoyant as the cork. These were fitted with the TPU sender gasket, although the gauge functions I suspect our initial thoughts on them not being as buoyant is the problem.

 

With the goal of re-fitting the tank the next day, I turned to Amazon for large pieces of cork. I ended up using two 50mm keyring floats, and cutting one in half did the trick perfectly. After doing some research, I found several recommendations to seal the cork to prevent it from drying out over time.

Re-fitting

Balls are too big for the hole..... 10 seconds on the belt sander, re-seal and we are finally good to go. 

A new wiring loom part 2 - Fuse holder and Relay Base

Main Aims 

- Improve reliability (existing wiring 79 years young)

- All circuits above negligible current operating via relays

- Minimise the current flowing through old switches in the dashboard

- Upgrade to modern head and spot lamps

- Reinstate Trafficators alongside new indicators

- Addition of hazard switch

- Addition of electric fan to cool engine

- Addition of electric fuel pump

- Provision of electric water pump

- Aux for USB sockets

- Additional interior light

- Upgrade from Dynamo to Alternator

- Replace starter solenoid

- Future proof with spare ways for fuses and relay

- Modern Thin wall copper cabling

- Modern fuse box and relay holder

There are many different fuse boxes available, some are pre-wired and others you build from scratch. I like the look of the MTA range of fuse boxes which are readily available in the UK. They offer a 16 way fuse holder, 4 way automotive relay base and a 7 way micro relay base. They are supplied complete completed with covers and come supplied with all the necessary connectors. They can also be connected together in any combination.

The initial draft required 1 x 16way fuse holder, 1 x 4way automotive relay and 1 x 7 way micro relay. The idea was micro relays for all the load switching and the 7 way base for the LED flasher relays.  Unfortunately the flasher relays are slightly too tall to fit with the lid so I ended up with 2 x 7 way relay base and remote mounting the flasher relays. 

I've used multiple suppliers for the re-wire including:

https://www.3waycomponents.co.uk/ - MTA Fuse Boxes

12 volt planet - Thin Wall Cable in a range of colours

Car Builder Solutions -  Wiring Accessories

https://www.3waycomponents.co.uk/ - MTA Fuse Boxes

Fuse Holder

Using a spreadsheet I listed all the circuits and divided them between the fuses based on power requirement. Some juggling required to observe the max current for 1mm or 2mm cable allowing for volt drop and heating due to bunching the cables together.  

Worth noting the numbers below are rounded up values with everything ON at the same time. In practice having measured the current with the car running the values are far lower. . 

Relays

The number is probably overkill but it does simplify the wiring and means the original switches on the dashboard and within the steering column only need to switch the current necessary to operate the relay coil. This massively reduces the load on the switches and they can happily operate for many more years. 

 
Fusebox prep

1st step was to add the feeds to the fuse holder. These are a combination of 1mm or 2mm wires. They will all need to be terminated at the supply side of the starter solenoid or battery. 

Sunbeam Talbot Ten - Adding 12v feeds to the fuse holder

The fuse holder and the relay terminals all use a similar type of crimp. 

Crimp connection to the fuse holder blade terminal

A new wiring loom Part 1 - Out with the old

From owning old cars electrical gremlins are the ones that let you down. The wiring on the Ten was original except the modifications to the head lamps, fitment of indicators and voltage regulator for a engine temperature gauge. For this, the loom was cut about and different wires added to suit. 

The build quality of the original loom is great. The loom is clipped to the chassis via brass nuts and bolts with steel p-clips. The cotton harness braiding is a delight and something you don't see now but at 79 years young an update is needed.

Sunbeam Talbot Ten Engine bay - old loom

Sunbeam Talbot Ten Engine bay - old fuse box &regulator, modern flasher relays

Sunbeam Talbot Ten Engine bay - reverse of old fuse box and regulator

Sunbeam Talbot Ten - original wiring to dashboard

Sunbeam Talbot Ten - original wiring to dashboard

Sunbeam Talbot Ten - Original Loom and cotton braid

Sunbeam Talbot Ten - Dashboard area

Sunbeam Talbot Ten - Original Loom with later additions

My main worry is the full current for the circuits run through the switches in the dashboard. I want to reduce this down to the bare minimum with the use of micro relays. For aesthetics I'm planning to refurbish the original fuse box in the engine bay and locate a new modern unit under the dashboard away from the elements. 

Paintwork restoration

Since purchasing the car I've been in regular contact with the son of a previous owner, it has been great to hear the stories of his late father owning the car and the changes he made during his ownership. His father put many hours into improving and polishing the paintwork. Sadly it was something that always let the car down and I'd assumed could only be corrected with a re-spray. 

My father-in-law came to stay over Christmas and was confident under the orange peel was decent paintwork lurking. The whole car was pretty much like the door below.

Started off with a mild cutting compound and a rotary polisher, overall not much of an improvement. It did confirm however the issue seemed to be the clear coat applied on top of the paint. We (FIL) then switched to 3000 grit wet and dry to cut back the top coat. I looked away at this point! 

Throughout the whole process no red paint was removed hence the assumption the issue was the top coat. 

Further machine polishing to remove the scratches from the wet & dry and the difference was stark. Paintwork has flecks and resembles metallic paint! 

At this point with one highly polished door there is no going back so we (FIL) proceeded to work over the whole car.

It has totally transformed the appearance of the car. 

Alternator Belt Sizing

 Bearing Boys have a helpful link to calculate the belt length by measuring the diameter and the centre distance. The centre distance is 440mm, crank pulley 126mm and alternator pulley 59mm. It suggests a pitch length of 1173mm.

The SPBX belt is designed to go around a smaller diameter pulley. I'll update once the belt arrives.

Dynamo to Alternator upgrade & Dynamator pulley shenanigans

As part of the upgrade to the head lamps it was clear we need a bit more power than the Dynamo could provide.  The Lucas C45 unit comes complete with fan to cool the engine, the bearings were in need of replacement. 

A couple of C45 Alternator upgrades are available, a cheaper option which is the Dynamator or a more expensive option. I've read the 2 units are different inside and one is made to a price point. They both retain the look of an original Dynamo which I wanted and the relative ease of mounting using existing brackets it seemed the easy choice. It doesn't come with a cooling fan so we also upgraded to an electric fan and mechanical thermostat. (see different post)

Wiring is easy with a 6mm cable to the battery and a single wire to the ignition light on the dash. It provides 40A, not a high valve compared to modern cars but covers what we need. 

Samuel turned some spacers from 16mm Aluminium bar stock to replace the washers used when aligning.

Crank Pulley

The Crank pulley was out of shape and we tried to straighten the best we can. It is a pressed steel affair which is brazed onto a mounting boss that fits on the crankshaft. I did look a re-manufacturing, again the Rootes Archive Trust came up trumps with the drawings but I can't justify the cost and unsure if I could sell a small batch to recover costs. 

The original crank pulley on the Ten is roughly based on an a SPB profile belt. On buying the car a previous owner had fitted a SPA belt which did the job but the wear rate was high as it didn't fit correctly. Dave Bamforth sourced the correct belt but with the change to the Dynamator a different length belt was required.

.

Image copyright - www.bearing-king.co.uk/

Image copyright - www.bearing-king.co.uk/

Dynamator Pulley Machining

The Dynamator pulley is fitted with a SPA belt profile which doesn't match the crank pulley. That leaves running the SPA belt and suffer excessive wear or machine the Dynamator pulley to match the Crank pulley. 

Not the easiest to machine and on our small Myford not the easiest to hold in the chuck. Using a ground down boring bar we could make the necessary 20 degree cut to remove enough material. Both SPA & SPB profiles have a 40 degree profile.

 

Capillary Temperature Gauge

 An advantage of the Hillman Minx Cast Iron cylinder head is a pocket to take a capillary temperature gauge. The gauge will be mounted under the dashboard. 

CBS - Durite 52mm Temperature Gauge

Front Indicators & Trafficator Upgrade

 The car was fitted with additional front indicators. Again they had used Halogen spot light bulbs which was totally overkill power wise and being mounted on the front bumper the cables were on show.

The new head lamps are fitted with side lamp which frees up the original front side light to be used as an indicator.  As part of the re-wire the Trafficators are back.