Lotus Elan Central

by **stu** » Fri 04.04.2008, 21:30

Looking for the thermal switch for the afterun pump this has packed up and caused a head gasket failure aaaaaargh :twisted:

Anyone got info. Chrissy Neals want £££££££

by **GeoffSmith** » Fri 04.04.2008, 21:40

That's the cooling fan switch as well. $52 from Rockauto.

by **Monty** » Fri 04.04.2008, 23:39

stu wrote::( Looking for the thermal switch for the afterun pump this has packed up and caused a head gasket failure aaaaaargh
Anyone got info. Chrissy Neals want £££££££

Are you talking about the Auxiliary pump that runs after the engines off and the temp is 3/4+, if so then that wouldn`t cause you a HGF as it`s extremely rare that these run. Yous should always let the cooling fans do the work, so if there on when your parking up you should let them run and only turn the engine of when the fans have switched off.

by **GeoffSmith** » Sat 05.04.2008, 11:04

On a new thread (now deleted) Stu wrote: Ok Geof...f..
This sensor s/w has it got one wire plug ? in other words thermal s/w to earth to operate ? is there no uk contact ?
Cheers

by **GeoffSmith** » Sat 05.04.2008, 11:09

The cooling fan temperature switch is indeed a single contact one - see the diagram in the Wiki. I don't know if there is a UK source but Rockauto are cheap and you should get it in a couple of days based on past experiences.

I took it that you overheated because the fans didn't cut it - as Monty says, the lack of a coolant pump is unlikely to cause the head gasket to go.

by **Monty** » Sat 05.04.2008, 15:03

Have you tested the pump to make sure thats working?

easy to do, stick a wire in to the wire loom for the thermal fan switch and earth on to the engine lift bracket the pump should be wroking with ignition off and the fans with ignition on.

by **clemo** » Sat 05.04.2008, 18:21

there is more to this than meets the eye...

the car was running with the wrong expansion tank top.
this has the wrong pressure release values (if any) as stu's car turned up to donny being pushed..

his header tank was blowing water out the top and into his single point coil (na)

i reckon this is all part of the same..

if he hadn't have put samco hoses on recently i rekon they would have been popping off by now..

i think this is a pressure related problem caused by the wrong expansion tank head.

the car has been boiling up (as normal) but the presssure is looking to blow out .. this has been at the weakest point being the head gasket...

has the radiator been replaced recently?

stu i have a head gasket set for na..
but 1st go and buy yourself a block tester...
they are £20 from a motor factors ..every elan owner should have one.

check that it is this

by **stu** » Sat 05.04.2008, 21:30

Thanks for that Clemo !
As to your question, the rads been recored in 2007 after total failure.
All has been well up untill about a week ago after a quick run...
Then also at Donny park....

Engine temp shows all fine ....
Nothing looked untoward even on the drive home from Donny park,very carefully.
The afterun pump sender unit has failed....So trying to source a new one!!!!! The advised website show nothing

As far as the gasket set, just bought one from SJs @ £80 inclusive

Cheers

by **Monty** » Sat 05.04.2008, 23:03

Stu,

Forgot yours is a NA :roll:

and didn`t know that it even has the `after-run` pump.

I bet your HG was going for a long time and thats why your Rad failed last year (to much pressure in the system) and the symptons have just got worst.

How do you know that it`s the switch thats failed?

by **GeoffSmith** » Sat 05.04.2008, 23:42

Monty wrote:I bet your HG was going for a long time and thats why your Rad failed last year (to much pressure in the system) and the symptons have just got worst.

Spot on.

by **paulwatkins** » Sun 06.04.2008, 08:13

Stu,
sorry to come to this late, but theres Engine gasket sets (A100E6183S) for the NA in the Lotus Aftersales list for £20.

Theres only a quantity of 3 shown, so I dont know if there will be any left. Worth a try?

Out of interest Clemo, what is the pressure rating of the yellow cap that Stu has, and the pressure rating of the correct black one?

by **stu** » Sun 06.04.2008, 13:50

Hi Monty
Checked the switch to ground everything runs, pump with ign off and fans with ign on...
Trying to source a new switch ,tried Rock auto but could not see anything to do with temp switches on that site

As i said earlier ive bought a gasket set from SJ sports £80 + but never mind eh.. :m100:

Cheers thanks for the help

by **clemo** » Sun 06.04.2008, 14:33

Monty wrote:Stu,

I bet your HG was going for a long time and thats why your Rad failed last year (to much pressure in the system) and the symptons have just got worst.

blimey monty you are a genius !

didn't think to ask about the radiator !

well did but did'nt want to give stu a complete kicking...

stu can you send the gasket set back?

by **Monty** » Sun 06.04.2008, 14:34

Stu,

So does that mean that your fans don`t kick in when the temp goes high ie 3/4 (don`t know if the NA is the same)

I had the same problem with Pinky1, fans wouldn`t kick in and though it was the thermal fan switch, so replaced it and that never cured the problem. The only way i sorted it was by crashing it in to the barrier and buying Pinky II LMAO :-D