What "Switch" in 2.6 Litre Engine - 2A

[Lionelgee]

Hello All,

Could someone please identify an unknown "switch" and describe what its function was?

I have one fully functioning 2.6 litre six cylinder motor out of a 2A, and a number of the same type of motors in the Series 3 vehicles. I noticed that there is a plate with a male bayonet fitting located on the head towards the top radiator hose mounting. The 2a engine has the fitting while my Series 3 engines do not - they just have a blank plate located in the same place.

I looked at my 1975 Series 3 Parts Catalogue and it states there is a "switch" Part Number 545010. There is no mention of what type of "switch" it is. There is also a note numbered with a circle of 2 that suggests that this switch was discontinued and replaced with the blank plate from November 1972 onwards.


So what was the switch and what role does it perform?

The main reason for finding this out is that the Series 2A motor with this switch is hooked up to an electronic ignition system and there are wires running from the black box that is connected with the choke cable that run to this unknown switch.

I am thinking of swapping this electronic system over to one of my Series 3 engines and it would be handy to know if this "switch" should come across in the conversion?

By the way the fourth attachment shows the black rectangular box that sits on the choke cable. The Parts Catalogue identifies this as Part Number 563318 and it is labelled - you guessed it "switch"! Can someone please let me know what this rectangular "switch" with two fittings on it is and what role does it play?


I have attached photographs that identify the bits and bobs. Thank you.

Kind Regards
Lionel

[Lotz-A-Landies]

I'll have to check the SIIA wiring diagrams when I get home, but from memory it is the choke warning light (thermocouple) switch.

When you pulled out the choke cable a switch (your image 4) was closed, a wire continued from this to the switch on the engine. When the engine came up to operating temp the thermocouple switch closed completed the circuit and the amber light on the dash illuminated.

Diana

[rover-56]

Lionel, the switch in the head is a water temperature sender, some models have a conventional threaded sender in a tapped hole on the rhs behind and below the one in your pic. The one in the cable switches the choke warning light as Diana said.

Terry

[PhilipA]

Yep, same in early Rangies. AFAIR , the light comes on at 60C or so to remind you to push the choke button in.
Regards Philip A

[JDNSW]

The cold start* warning system on all Series 1.2.2a and, I think, some 3, comprises three bits - a thermal switch on the head, which is what you refer to, a switch on the cold start control cable, and an orange warning light on the dash, plus the wiring between them.

It is intended to come on when the "choke" is pulled out and the engine reaches a temperature that allows it to run with it pushed in.

John

*Rover used the term "cold start" rather than "choke", because the Solex carburettors, used until the mid sixties, did not have a cold start device that could strictly be called a choke - it does not restrict air, but adds petrol.

[Lotz-A-Landies]

Hi Lionel

Just to hyjack your thread a little.

If you are using a SIIa 6cyl in your Army SIII there are a couple of things to consider.

The Army units didn't use the SU carby but a Stromberg CDI.

The Army ones used a Bosch dissy the civvy ones a Lucas.

The civilian lifting brackets only have a small slot, the army ones had a large hole through which you could sling a chain.

If you want people to overlook the origins of your engine, it may be worthwhile swapping over these bits.

Diana

[Lionelgee]

Hi Lionel

Just to hyjack your thread a little.

If you are using a SIIa 6cyl in your Army SIII there are a couple of things to consider.

The Army units didn't use the SU carby but a Stromberg CDI.

The Army ones used a Bosch dissy the civvy ones a Lucas.

The civilian lifting brackets only have a small slot, the army ones had a large hole through which you could sling a chain.

If you want people to overlook the origins of your engine, it may be worthwhile swapping over these bits.

Diana

Hello Diana,

I have a totally civilian Series 3 ute that was originally fitted with a six cylinder motor. I bought it with a Holden 202 motor. The previous owner said that it had started to jump out of top gear when going down hill or cruising along flats - not under load. From what little I know about the Holden conversions this signals alignment issues and a box with a limited lifespan.

One option I have is to take out the Holden 202 and the gearbox and replace it with the gearbox from my Series 3 stock diesel and mate it to the Series 2A engine. The Holden conversion was never approved by Queensland Department of Transport although the conversion was done professionally in Maryborough. This means there are no blue plates fitted to it.

Carburettor wise: the 2A has a Zenith Stromberg CD 175 s. My 1978 ex-Army Land Rovers have the CD 175. My 1980 FFR has a CD 175 2.

Sparks: Yes all the army stuff is Bosch.

The 2A is all Lucas and other electronic conversion parts.

Kind Regards
Lionel

[Lionelgee]

The cold start* warning system on all Series 1.2.2a and, I think, some 3, comprises three bits - a thermal switch on the head, which is what you refer to, a switch on the cold start control cable, and an orange warning light on the dash, plus the wiring between them.

It is intended to come on when the "choke" is pulled out and the engine reaches a temperature that allows it to run with it pushed in.

John

*Rover used the term "cold start" rather than "choke", because the Solex carburettors, used until the mid sixties, did not have a cold start device that could strictly be called a choke - it does not restrict air, but adds petrol.

Hello John,

Thank you for the reply. So the cold start = choke warning light is similar to what I may remember the EH Holden used to have. It was with a cluster of three lights. The other two were too late lights - once the lights came on your engine was just about history!

Kind Regards
Lionel

[Lionelgee]

Lionel, the switch in the head is a water temperature sender, some models have a conventional threaded sender in a tapped hole on the rhs behind and below the one in your pic. The one in the cable switches the choke warning light as Diana said.

Terry

G'day Terry,

From your description I might have tracked down the site of the "conventional threaded sender" located on the block below where the plate is? The photographs of the site are on a Series 3 block made in 1978.

The other photographs show different angles of the Cold Start switch that was taken off the 2A motor attached to the CD 175 s carburettor.

This was done to eliminate the carburettor as a possible cause of the Series 3 motor not starting. I knew the 2A engine's carburettor worked well and made the engine purr. It turns out the Series 3 CD 175 had a very seized main piston. I have since got this carburettor sorted out and running on the 2A engine, so it is going back on the Series 3. The 2A's carburettor will be going back on the 2A engine again to keep it original to how it first arrived here.

Kind Regards
Lionel

[Lotz-A-Landies]

Hello Diana,

I have a totally civilian Series 3 ute that was originally fitted with a six cylinder motor. I bought it with a Holden 202 motor. The previous owner said that it had started to jump out of top gear when going down hill or cruising along flats - not under load. From what little I know about the Holden conversions this signals alignment issues and a box with a limited lifespan.

One option I have is to take out the Holden 202 and the gearbox and replace it with the gearbox from my Series 3 stock diesel and mate it to the Series 2A engine. The Holden conversion was never approved by Queensland Department of Transport although the conversion was done professionally in Maryborough. This means there are no blue plates fitted to it.

<snip>

Kind Regards
Lionel

Hi Lionel

A series box slipping out of top may actually be the 3rd/4th synchro cones, the detent springs around them or wear on the bronze bush supporting 3rd gear +/- too much end fload on the thrust washer between 2nd and third. As you say it could have been caused by an out of alignment adaptor.

The diesel gearbox will need a SIII 6cyl bellhousing (but you likely have one of those on the dodgy box behind the 202). Otherwise I have a spare.

Diana