Thermostat

Author
Discussion

Chim450

1,452 posts

261 months

Friday 7th September 2012
quotequote all
I agree with the fact that changing the Thermostat will not change the running temperature problems. Are you using up a lot of coolant? If you are and there are no obvious leaks, then the possible culprits are; dodgy radiator, dodgy heater matrix, dodgy hoses, silted up water channels and finally and the most undesirable, a cracked block or head gasket. These last two though would probably have other signs, such as; lumpy running, white smoke from the exhausts, mayonnaise on the oil filler cap etc....

S6 Devil

Original Poster:

3,556 posts

233 months

Friday 7th September 2012
quotequote all
Thanks guys!

Ahh, I didn't know that changing the thermostat for a lower temp one won't change the ultimate running temp of the engine, just help heat the oil sooner. That's a relief to hear...all sorts of worst case scenarios were going on in my head!!!

No, it's not using up any coolant at all and no leaks. The radiator is an aluminium one, fitted by Power when the engine was rebuilt 8000 miles ago and is in fine fettle. Both fans work and kick in at the right temps. The engine runs beautifully, no lumpiness, white smoke from the exhaust or mayo on the oil filler cap.

Coolant sensor is in the post and will be fitted as soon as it arrives. I will report back! Many thanks thumbup

Edited by S6 Devil on Friday 7th September 23:26

Basil Brush

5,080 posts

263 months

Friday 7th September 2012
quotequote all
S6 Devil said:
Thanks. Any feedback on the answer to your earlier question about the symptoms.

"Yes, odd temps but engine and fans seem fine. It runs at between 91 and 94 on the move but when stationary slowly creeps up. It got to 110 yesterday when I let it idle at home after a run. I switched it off sharpish!"
Do you mean it got to 110 without the fans kicking in, or that temp with the fans on?

The dash and ECU are fed by different temp sensors so it's possible that the dash can display odd temps but the ECU, and therefore the fans, are getting the correct signals. If it's creeping up to 110 with the fans coming on though that sounds like a different issue.

S6 Devil

Original Poster:

3,556 posts

233 months

Friday 7th September 2012
quotequote all
Basil Brush said:
Do you mean it got to 110 without the fans kicking in, or that temp with the fans on?

The dash and ECU are fed by different temp sensors so it's possible that the dash can display odd temps but the ECU, and therefore the fans, are getting the correct signals. If it's creeping up to 110 with the fans coming on though that sounds like a different issue.
Yes, it's creeping up to 110 with the fans on. Surely the ecu is telling the fans to kick in so would seem to be ok. It must be the dash sensor that is faulty...yes?

Any idea where the dash sensor is?

Edited by S6 Devil on Friday 7th September 23:33

Basil Brush

5,080 posts

263 months

Saturday 8th September 2012
quotequote all
Same side as the ecu sender but towards the front of the engine. It is the same as the oil temp sensor with a short cable coming out of it and a plug on the end.

S6 Devil

Original Poster:

3,556 posts

233 months

Saturday 8th September 2012
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Basil Brush said:
Same side as the ecu sender but towards the front of the engine. It is the same as the oil temp sensor with a short cable coming out of it and a plug on the end.
Bu**er, looks like I've bought the wrong one! I've ordered the one for the back of the engine.

I'm puzzled though.

The one at the front is described by RG as: the temperature sensor for the ECU

"Thermistor, coolant temperature sensor
Part No TVR M1275
To fit TVR Speed Six engines. This is the front sensor in the TVR Speed 6 cylinder head and is the temperature sensor for the ECU"

RG's description of the one at the back is that :The coolant temperature sensor sends it's information direct to the ECU

"Sensor, coolant temperature
Part No TVR N0113
Coolant temperature sensor is compatible with all TVR Speed 6 engines and AJP V8s. The coolant temperature sensor sends it's information direct to the ECU, failure of this sensor can result in major running problems and overheating"


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As I've ordered the one for the back of the cylinder head, I guess I'll have to try this one first and if no joy move to the other one...hohum!

dvs_dave

8,609 posts

225 months

Sunday 9th September 2012
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Robertjp said:
remember it doesnt run on post vista machines....
Yes it does. Windows Vista Pro and above. It comes with an XP virtual PC mode and it works flawlessly with the serial to USB adapter. smile

dvs_dave

8,609 posts

225 months

Sunday 9th September 2012
quotequote all
S6 Devil said:
Yes, it's creeping up to 110 with the fans on. Surely the ecu is telling the fans to kick in so would seem to be ok. It must be the dash sensor that is faulty...yes?

Any idea where the dash sensor is?
I had this and couldn't figure out the cause. Turned out to be low coolant level due to a pinhole in the top of the rad so any leaking fluid just evaporated immediately hiding any obvious telltale leak, until it finally went properly and leaked all over the garage floor.

I also learned that checking the coolant level is actually quite difficult and very easy to be mistaken with. Just seeing some coolant in the neck of the header tank is not enough as it does actually pool there irrespective of actual coolant level. You have to actually be able to see a 10-15mm depth and it properly sloshing around in there when you shake the car. That ensures that the level in the tank is the same as what you see in the filler neck.



S6 Devil

Original Poster:

3,556 posts

233 months

Sunday 9th September 2012
quotequote all
dvs_dave said:
I had this and couldn't figure out the cause. Turned out to be low coolant level due to a pinhole in the top of the rad so any leaking fluid just evaporated immediately hiding any obvious telltale leak, until it finally went properly and leaked all over the garage floor.

I also learned that checking the coolant level is actually quite difficult and very easy to be mistaken with. Just seeing some coolant in the neck of the header tank is not enough as it does actually pool there irrespective of actual coolant level. You have to actually be able to see a 10-15mm depth and it properly sloshing around in there when you shake the car. That ensures that the level in the tank is the same as what you see in the filler neck.
Dave you're a star! wink I checked the coolant level and found it very low. There was a pool in the filler neck which fooled me into thinking it was full. I have topped it up so there is a 10-15mm depth in the neck. I took it for a run and now when the fans kick in the temp starts coming down...phew what a relief! thumbup

Anyone need an uprated Bosch temp sensor?

Robertjp

2,281 posts

225 months

Sunday 9th September 2012
quotequote all
dvs_dave said:
Yes it does. Windows Vista Pro and above. It comes with an XP virtual PC mode and it works flawlessly with the serial to USB adapter. smile
just to reiterate i said *post* vista machines wink

Virtual mode doesnt work on win 7...

Robertjp

2,281 posts

225 months

Sunday 9th September 2012
quotequote all
S6 Devil said:
Dave you're a star! wink I checked the coolant level and found it very low. There was a pool in the filler neck which fooled me into thinking it was full. I have topped it up so there is a 10-15mm depth in the neck. I took it for a run and now when the fans kick in the temp starts coming down...phew what a relief! thumbup

Anyone need an uprated Bosch temp sensor?
so do you think you have a leak?


Basil Brush

5,080 posts

263 months

Sunday 9th September 2012
quotequote all
Ah the good old basic checks first. smile

S6 Devil

Original Poster:

3,556 posts

233 months

Sunday 9th September 2012
quotequote all
Robertjp said:
so do you think you have a leak?
Yes, found a leak under the expansion tank to thermostat hose. Tightened up and all seems good. I will keep a close eye on the coolant level and see how it goes. The car is due a service soon so I will get it all checked out then and maybe fit some ACT silicone hoses for peace of mind.

S6 Devil

Original Poster:

3,556 posts

233 months

Sunday 9th September 2012
quotequote all
Basil Brush said:
Ah the good old basic checks first. smile
Thanks for your input. Bit of a schoolboy error!

Chim450

1,452 posts

261 months

Sunday 9th September 2012
quotequote all
Chim450 said:
I agree with the fact that changing the Thermostat will not change the running temperature problems. Are you using up a lot of coolant?
S6 Devil said:
No, it's not using up any coolant at all and no leaks
rolleyes


biggrin

Edited by Chim450 on Sunday 9th September 23:28

S6 Devil

Original Poster:

3,556 posts

233 months

Monday 10th September 2012
quotequote all
Chim450 said:
rolleyes


biggrin

Edited by Chim450 on Sunday 9th September 23:28
Haha. In fairness it seemed not to be losing coolant and no leaks were evident. It was only when I ran the car with the main bonnet off that I found one. It was dripping onto the bottom of the engine and evaporating as fast as it was coming out. No puddles were collecting under the car.

I now know to check the coolant level more carefully and not just assume that the puddle in the filler neck indicates that it is full. Lesson learnt!
wink

Robertjp

2,281 posts

225 months

Monday 10th September 2012
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good news you found something smile

There is a silicon hose set for a sagaris on the PH classifieds at moment...not sure how different they are to a Tuscan...but comparing the two there are some different hoses, just not sure if you could make up the set with the odd missing pipe for the Tuscan.

I considered it but the guy never responded to me...and i think i want to be a tart and have red hoses hehe

Basil Brush

5,080 posts

263 months

Monday 10th September 2012
quotequote all
S6 Devil said:
Thanks for your input. Bit of a schoolboy error!
I've been there many times!

m4tti

5,427 posts

155 months

Monday 10th September 2012
quotequote all
dvs_dave said:
I had this and couldn't figure out the cause. Turned out to be low coolant level due to a pinhole in the top of the rad so any leaking fluid just evaporated immediately hiding any obvious telltale leak, until it finally went properly and leaked all over the garage floor.

I also learned that checking the coolant level is actually quite difficult and very easy to be mistaken with. Just seeing some coolant in the neck of the header tank is not enough as it does actually pool there irrespective of actual coolant level. You have to actually be able to see a 10-15mm depth and it properly sloshing around in there when you shake the car. That ensures that the level in the tank is the same as what you see in the filler neck.
Interesting.. im pretty sure ive got about 4/5mm in the neck of the coolant tank. If I fill it up to 15mm it simply over flows. The temp never goes beyond 95 even when sitting in traffic. Every part of the cooling system has been replaced aswell.

S6 Devil

Original Poster:

3,556 posts

233 months

Monday 10th September 2012
quotequote all
Robertjp said:
good news you found something smile

There is a silicon hose set for a sagaris on the PH classifieds at moment...not sure how different they are to a Tuscan...but comparing the two there are some different hoses, just not sure if you could make up the set with the odd missing pipe for the Tuscan.

I considered it but the guy never responded to me...and i think i want to be a tart and have red hoses hehe
I also considered them but I don't know which would fit the Tuscan. TVR Power have both sets but I'm not sure that many would be transferable from the photos.

Tuscan



Sagaris