Wiring Appendix II Technical Notes

(Not intended for the experts !!)

There is a lot of information regarding wiring a Robin Hood (most of which can also relate to other Sierra based kit cars) on the RHOCaR web site. Although this is excellent it is very fragmented, but where applicable the text underlined in blue will give a hyperlink to the additional information. The notes below give a very brief idea of the function of some components, and how they operate. If you know how it works it is much easier to fix !!

Crimping:-

Virtually ALL Aerospace and Automotive wire connections are CRIMPED and not soldered. A correctly crimped connection is generally considered to be a better long term connection than a soldered joint, particularly on stranded wires. It is also cheaper, faster and has less possibility for error.

Column Switch Unit:-

It is essential to determine the date of this unit before starting, as the early and late units vary, and your wiring will need to reflect this change. Remove the Steering Wheel and the date code is on the switch LH (some codes are on the RH) front vertical face. Look for 83 BG (1983 unit) or 87 BG (1987 unit) There is also a 90 BG (1990 unit) but this unit is the same as the 1987 units. The BG is the Sierra code. The other numbers are irrelevant.

Relays:-

A Relay or Solenoid is an electrically operated switch. This can be an electronic, mechanical device or even thermal. (Thermostat) Its main use in car electronics is to enable a small light duty switch to turn on a much larger high current device(s). It can also be used to switch on a number of (connected) devices, such as a Rear Fog Light and the Warning light. Relays can very often be the cause of a circuit failing to work. To test the relay, put 12 volts across the input terminals, and check that the output terminals open or close using your Avo or Continuity tester.

Fuses:-

These are a safety device to prevent damage to a unit, protect against short circuits or the overload of wiring, which can lead to fire. If a fuse fails always find out why. Do not put in a bigger fuse in the hope that the problem will go away. If in doubt check with the Continuity tester. A failed fuse is usually visible by eye.

Wire:-

Always use colour coded stranded copper wire of the correct current rating. (Number of strands and wire diameter) Use of incorrect wire leads to poor performance and overheating which may lead to fire. A proper " bought out " loom will have of course have correctly rated wire.

Clip to the wires to the chassis at regular intervals using plastic tywraps to avoid chaffing, where possible lace or tape and fit into trunking. See the original loom and methods employed by Ford etc.

Bulbs:-

The following is a list of all the bulbs used on a standard Robin Hood 2b.

Ignition Module:-

Ford used a number of these modules starting with a simple Transistor unit and going on to fully Electronic Modules with "mapped" ignition timing linked to a wide variety of external inputs, particularly on Injection Engines. It is essential that you match the Module, Coil & Distributor to the correct engine. The chart below shows which modules & distributors fitted which engine. Injection engines MUST use the complete Sierra donor system. (at least until you know what you are doing.) The module must be mounted on a substantial Heat Sink. Some engines used a "built in " distributor. (CVH) so if you are using a standard Pinto take care to select compatible units. The Bosch Inductive System & Transistor Module is recommended by some builders for simple SOHC Carburettor Pinto's.(highlighted in RED) These units are getting a bit scarce, if you see one buy it.

Coil:- (Type a) All engines seem to use the same coil ??

25.0 kv

Primary winding resistance 0.72 to 0.88 ohms

Secondary winding resistance 4500 to 7000 ohms

See Appendix VIII for Transistor Ignition Module Pin Out

Cooling System Electric Fan:-

This unit requires special circuit arrangements for optimum performance. See Section XVI The Cooling System and Fan with particular reference to the RHOCaR link.

Sierra Engine Codes

The Engine ID Code is stamped on the Crankcase/Bellhousing mounting web on the drivers side, (the large bolt hole just behind the exhaust manifold) in general the 3rd letter can be ignored. Unleaded heads are stamped with a code on the cylinder head, next to No. 4 spark plug. The engines stamped with these codes can be run on unleaded fuel but the Ignition timing must be set as follows:- (c/o the Haynes Manual) As a general rule try and use a tankful of leaded 4 star every fourth tankfull of unleaded. Also the Timing belt cover is marked with a white painted letter F but this is not a 100% guarantee as the cover may have been changed in the past.

CASTROL sell Valvemaster plus. A lead replacement petrol additive and octane booster. Recommended by the MG Car club of GB. What Castrol do not know about oil/petrol is is probably not worth knowing !!

More comprehensive details in Haynes Chapter 4 Pg 143.or the Des Hammill/Peter & John Wallage books.

Pre SVA or MOT Check

Before you go for your SVA or MOT at least check all the following are fully functional:-

And this is a simple car !!

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© Colin Usher 2008