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Early S3 aluminium radiator piping


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Hi, I am in the process of replacing both aluminium radiator pipes and both aluminium heater pipes (running through the chassis) on my right hand drive early S3 Esprit. The otter switch is near the water pump in the rear of the car and not at the radiator end. I have looked at various radiator layout diagrams in the manual and have the following questions.

1. Are both aluminium heater pipes meant to be the same length?

2. I notice the passenger side aluminium radiator pipe has a large bend on the pipe where it exits the chassis and it then connects via a hose to the radiator. Is that correct?

3. I also notice the drivers side aluminium radiator pipe does not have a bend but exits the chassis and has a small length of straight rubber radiator hose which then connects to a short length of curved aluminium pipe and then to a radiator house and then to the radiator. Is that correct?

4. Are the rubber grommets for the heater hoses and the radiator hoses where they pass through the chassis still available?

I ask because the front end does not appear to be original according to the diagrams in the manual. I have removed all four pipes and all are corroded.

Thanks for helping


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I believe that both the coolant pipes have bends at the front of the car. I also think that the otter switch should be at the front of the car attached to a curved pipe just before the radiator. It sounds like someone has 'adjusted' your car. 🙂

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It's getting there......

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Thank you. The Esprit Manual I have shows the otter switch at the front as you say but the manual also says Esprit S3 cars prior to mid 1985 and USA Turbo models have the otter switch fitted into the water pump outlet pipe. The exploded view of the USA Turbo does show the otter switch in the water pump outlet pipe which is in the engine bay. 


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1 hour ago, Spin said:

If anyone has an early S3 NA 1981/1982 Esprit, could they please have a look or post a photo of the two aluminium pipes where they exit the front chassis to confirm if both aluminium pipes exit with a bend. 

As I understand, 2-fan models have a straight pipe on the RHS of the car, and 3-fan models have a pipe with a bend on the RHS.  The radiators are slight different. But fitting a straight pipe on the RHS isn't a fatal course action as you can purchase generic silicone coolant hoses to suit.

That is what I did when I replaced the alloy pipes on my year 1983 S3 NA with self-fabricated stainless steel pipes.

The aluminium elbow in which the Otter switch is located are the same in both configurations, just that the rubber hoses are slight different.


Edited by ekwan
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