1984 Turbo Esprit overheating after 48 hours of ownership! Seriously worried!

[GreenGoddess]

That’s great info, thank you guys. 
So when cold, the coolant should be 3/4 of the way UP the header tank? Mine is 3/4 DOWN when cold. 
 

I may just install a new otter switch if I can’t figure out what the trigger temperature is supposed to be. If I don’t know the trigger temp then I can’t test the one that is already installed. 

[Elite 4.9]

One thing I also have done on my Elite with a very modified aluminum engine, which is very sensitive to overheating and one can tell with his right foot when this occurs, is to put a separate switch that enables me to turn on my electric radiator fans when ever I want to. So if I know I am going to be sitting in traffic or I see my temps going up, I can turn it on. And of course you can also had an oil cooler.

[GreenGoddess]

38 minutes ago, Elite 4.9 said:

One thing I also have done on my Elite with a very modified aluminum engine, which is very sensitive to overheating and one can tell with his right foot when this occurs, is to put a separate switch that enables me to turn on my electric radiator fans when ever I want to. So if I know I am going to be sitting in traffic or I see my temps going up, I can turn it on. And of course you can also had an oil cooler.

Thank you. I was going to add a manual override switch but I have been warned that the Esprit does not like having the fans running at max power for any length of time due to the cars wiring. There is a factory fitted thermal cutout switch fitted for that purpose. 
 

I think the Esprit’s already have oil coolers fitted as far as I am aware. 

[TAR]

On 26/08/2022 at 19:46, GreenGoddess said:

My otter switch is on the top of the radiator pipe under the wheel arch

It should be facing down. I suspect the hard pipe has been put on upside down.  

[GreenGoddess]

19 minutes ago, TAR said:

It should be facing down. I suspect the hard pipe has been put on upside down.  

Early cars had it fitted to the top of the pipe. Later models were fitted with a new pipe with the otter switch at the bottom. So I’ve read online anyway. 

[GreenGoddess]

I have decided I’m going to replace the coolant temp sensor, the otter switch (fan switch) and the thermostat just to be on the safe side. It will give me peace of mind. 
 

Newbie question: Where is the thermostat and do you have any tips for changing it?

[jonwat]

Take a look in the parts manual engine/water pump & use a new gasket 

Edited August 28, 2022 by jonwat

[snowrx]

From one of the manuals;

Cars used in hot climates a r e f i t t e d w i t h a b l u e c o l o u r coded switch
which makes/breaks a t temperatures of 82/72OC. The switching point f o r
c a r s i n temperate climates was r a i s e d from 86/76 t o t h e 92/82 of the
c u r r e n t green colour coded switch.

A thermometer and a continuity meter can check the setpoints as you heat it in a pan of water on the stove. I assume they are stating "Close/Open" temps above, ie Cose at 92C/ Open at 82C.

[TAR]

You may have some searching to do if you want a new thermostat.

Cars before MY87 used an exterior thermostat in a non removable cover.

I think they were used on old Mercedes cars from the 1950's  

[GreenGoddess]

2 hours ago, snowrx said:

From one of the manuals;

Cars used in hot climates a r e f i t t e d w i t h a b l u e c o l o u r coded switch
which makes/breaks a t temperatures of 82/72OC. The switching point f o r
c a r s i n temperate climates was r a i s e d from 86/76 t o t h e 92/82 of the
c u r r e n t green colour coded switch.

A thermometer and a continuity meter can check the setpoints as you heat it in a pan of water on the stove. I assume they are stating "Close/Open" temps above, ie Cose at 92C/ Open at 82C.

That’s fantastic info! Thank you. I heated my otter switch in boiling water and couldn’t get a continuity reading. Perhaps that’s my car’s problem. If so, it’s a nice easy fix. 🙏

2 hours ago, TAR said:

You may have some searching to do if you want a new thermostat.

Cars before MY87 used an exterior thermostat in a non removable cover.

I think they were used on old Mercedes cars from the 1950's  

Ugh, I don’t like the sound of that. Thank you 🙏 

[GreenGoddess]

2 hours ago, TAR said:

You may have some searching to do if you want a new thermostat.

Cars before MY87 used an exterior thermostat in a non removable cover.

I think they were used on old Mercedes cars from the 1950's  

Is this the blighter?

[ekwan]

Perhaps you should look at diagnosing things logically, step by step before diving in at the deep end.

First of all, any coolant or engine contamination, or if the levels are drastically raised or lowered (expansion due to heating excepted). Then, check if your coolant is really at 120C, thermometer in the coolant tank or an infra thermometer pointed at the correct places. If the above checks out, perhaps and only perhaps I'd start pushing the panic button, may just as there are other small issues like temperature sensors or even a non working cooling fan due to failed thermo switches, witing, relays or fuses. 

[snowrx]

MY '85 has the thermostat in the top of the water pump below the hose elbow, but its a USA car and might have been switched by a prior owner.

[910Esprit]

8 hours ago, GreenGoddess said:

Is this the blighter?

Yes - Its tucked away at the front of the engine at the lower right hand side.  Access will be tricky!   If someone can remember the brand name, they do appear on Ebay, but be aware there are several similar looking variants

 

1 hour ago, snowrx said:

but its a USA car

Its completely different from a UK domestic 1984 LC model, with regards to sensors, thermostat, piping, water pump, cylinder head stubs etc....   Pretty much the only 1984 domestic market difference would be the water pump if it is an AC/non-AC model  From GG's earlier descriptions we know its not been retrofitted with the later 'aftermarket' HC cooling kit.

Edited August 29, 2022 by 910Esprit

[GreenGoddess]

6 hours ago, ekwan said:

Perhaps you should look at diagnosing things logically, step by step before diving in at the deep end.

First of all, any coolant or engine contamination, or if the levels are drastically raised or lowered (expansion due to heating excepted). Then, check if your coolant is really at 120C, thermometer in the coolant tank or an infra thermometer pointed at the correct places. If the above checks out, perhaps and only perhaps I'd start pushing the panic button, may just as there are other small issues like temperature sensors or even a non working cooling fan due to failed thermo switches, witing, relays or fuses. 

Thanks. I did try an infrared thermometer but it was completely useless. I may buy a better one and try again. 

[GreenGoddess]

7 minutes ago, 910Esprit said:

Yes - Its tucked away at the front of the engine at the lower right hand side.  Access will be tricky!   If someone can remember the brand name, they do appear on Ebay, but be aware there are several similar looking variants

 

Its completely different from a UK domestic 1984 LC model, with regards to sensors, thermostat, piping, water pump, cylinder head stubs etc....   Pretty much the only 1984 domestic market difference would be the water pump if it is an AC/non-AC model  From GG's earlier descriptions we know its not been retrofitted with the later 'aftermarket' HC cooling kit.

Thanks. In that case I will try and confirm that the thermostat is working rather than just jump in and change it. 
 

What’s the easiest way to test the thermostat without removing it?

[ekwan]

1 hour ago, GreenGoddess said:

Thanks. In that case I will try and confirm that the thermostat is working rather than just jump in and change it. 
 

What’s the easiest way to test the thermostat without removing it?

By feeling the pipe downstream of the thermostat while the engine is warming up. It should suddenly feel warm as the thermostat open up. 🤣

Otherwise, try running the engine without the thermostat and see if overheating still occurs. 

Needless to say which is the easier option.

Edited August 29, 2022 by ekwan

[GreenGoddess]

2 hours ago, ekwan said:

By feeling the pipe downstream of the thermostat while the engine is warming up. It should suddenly feel warm as the thermostat open up. 🤣

Otherwise, try running the engine without the thermostat and see if overheating still occurs. 

Needless to say which is the easier option.

Thank you. Would the pipe that houses the otter switch be a good place to feel? 

[ekwan]

2 hours ago, GreenGoddess said:

Thank you. Would the pipe that houses the otter switch be a good place to feel? 

There are a few variations of flow patterns for the S3. You have to see (from the workshop manual) which is yours and trace the pipe that comes off the thermostat outlet.

[TAR]

If you go as far as removing the thermostat, you can test it by pouring boiling water into it. You'll need to block the bypass outlet but it should open and let the water pass through. You can easily see inside it through the openings.  

[drdoom]

On eBay, search "Behr" when seeking the thermostat.

Cheers

[GreenGoddess]

22 hours ago, ekwan said:

There are a few variations of flow patterns for the S3. You have to see (from the workshop manual) which is yours and trace the pipe that comes off the thermostat outlet.

Thank you. Where will I find the workshop manual? Is it on this site if I subscribe? (I could only see an offer for the parts manual). 

[ChrisJ]

The Parts manual is available when you upgrade to Full Forum Member.

For the workshop manual, SWLC have them: Lotus Esprit Turbo + S3 Service Notes 1980-87 - The South West Lotus Centre Ltd (thelotuscentreonline.co.uk)

 

[GreenGoddess]

1 hour ago, ChrisJ said:

The Parts manual is available when you upgrade to Full Forum Member.

For the workshop manual, SWLC have them: Lotus Esprit Turbo + S3 Service Notes 1980-87 - The South West Lotus Centre Ltd (thelotuscentreonline.co.uk)

 

Perfect. Thank you 🙏 

[TAR]

Service manuals occasionally pop up on eBay as well at varying prices.