Suspect failed thermostat

[Ootohere]

Cold snap and winter formulation diesel and the rise in fuel usage. 

Ridiculous but as winter comes so does what can be expected with winter motoring if temperatures are lower.

Longer warming up time to efficient operating temperatures and more drain on the battery.

[brianja138]

 to do the 'stat whilst they are in there?  £413.15!!  

Can that really be correct? Even without trade discount these cannot cost more than £40 plus fitting, I would have thought. Personally I would try another place for a comparison quote.

[Ryeman]

OK, so the recent cold snap has brought this back.  I left it last time but this time I am investigating a fix.  The car is going in for a cambelt and water pump change in a couple of weeks, so I asked how much extra to do the 'stat whilst they are in there?  £413.15!!  That is more than the price to do the cambelt!  I have asked them if they have quoted me for a standalone job, rather than an incremental one (seeing as though the coolant has to be dropped out anyway to do the pump and all the covers and many parts will be off of it - I'd have expected a few quid in parts and maybe an extra hour of labour).

 

Let's see how far customer loyalty goes, especially seeing as though they 'owe me one' for previous ****-ups.

 

Going back to the cold weather behaviour, one other factor I have noticed is a significant drop in fuel economy (same happened last winter).  I barely get 500 miles between fills now, whereas I would usually expect at least 550.  Aside from the weather, all other factors remain 'constant' (as constant as driving on open roads can get).

Have they made an attempt to justify that ridiculous figure?.

[muddyboots]

If you're interested, you can get hold of the Skoda workshop manuals via Erwin; IIRC it's only about £6-£7ish to get an hours access, it's surprising what you can download in that time.

You'd then be able to see what was involved, and know whether the £413 is anywhere near justified. And also whether to try doing it yourself...

[weasley]

Have they made an attempt to justify that ridiculous figure?.

 

They said they'd call me back.  Of course, they haven't.  I've just called again - "busy, can we call you back?".  My breath is bated.

 

[uPDATE] they have called as I was typing this.  However it's a new person who doesn't know the back story, so I tell it again.  And the outcome....?  £80.89 extra, fitted.

 

If you're interested, you can get hold of the Skoda workshop manuals via Erwin; IIRC it's only about £6-£7ish to get an hours access, it's surprising what you can download in that time.

You'd then be able to see what was involved, and know whether the £413 is anywhere near justified. And also whether to try doing it yourself...

 

Worth thinking about, although there's no way I'm doing the cambelt and pump, so I though I would just add this little extra to the job whilst they have it open.  Surely the 'stat is on the other end of the water pump outlet pipe anyway, which has to come off?!  For £80 (see update above) they can do it.

[Ryeman]

They said they'd call me back.  Of course, they haven't.  I've just called again - "busy, can we call you back?".  My breath is bated.

 

[uPDATE] they have called as I was typing this.  However it's a new person who doesn't know the back story, so I tell it again.  And the outcome....?  £80.89 extra, fitted.

 

 

Worth thinking about, although there's no way I'm doing the cambelt and pump, so I though I would just add this little extra to the job whilst they have it open.  Surely the 'stat is on the other end of the water pump outlet pipe anyway, which has to come off?!  For £80 (see update above) they can do it.

What's a zero or a five between friends.......it seems

[vRS G60]

Might as well reply to this rather than starting a new thread.

My 60 plate 1.2 petrol Yeti has always taken a while to get to 90° when the weather is cold but lately it's been hovering below that.

I've started a new job and it's only 8 miles to work, my previous journey to work took me over the moors so the engine was working harder going up the hills.

But when it hit 90° it always stayed there.

The heater gets warm but the temperature gauge takes 2 or 3 miles before it moves and has been stopping at around 80° or getting to 90° then dropping again.

I've also noticed it dropping if I stop at traffic lights.

The speed limit is 50 mph and the 2nd half the journey is downhill, (the uphill is a steady climb, not too steep).

Has anyone else seen this on a petrol engine?

[Urrell]

4 hours ago, vRS G60 said:

Might as well reply to this rather than starting a new thread.

 

Sounds just like a stuck open thermostat.

[vRS G60]

My thought too.

I'm trying to find out how much they are and how easy to replace,

[Urrell]

26 minutes ago, vRS G60 said:

I'm trying to find out how much they are and how easy to replace,

Looks like there are 2, one on the main circuit which I take is the block and the other on the head.
None easy but it sounds like your heater is working so the head one should be OK.
This shows the main circuit thermostat and there is a bit of dismantling before even getting to here.

 

[Austin 7]

Hi vRS G60.  Probably worth noting that many modern cars, Yeti included, have software between the engine coolant temperature sensor and the dashboard gauge.  This is designed to show a rock solid 90 degrees or centre scale for any temperature which is in the acceptable range, e.g. 75 to 105 degrees C.  I presume this is done to avoid worried drivers nagging their dealers unnecessarily. So, if the engine is properly warmed up and still doesn't stay at 90, you can be fairly certain it's being over cooled.  The heater radiator is rated at perhaps 5 kW and the main radiator at perhaps 50 kW or more, so it seems unlikely that the heater is robbing enough to cause over cooling.  My Yeti is a petrol 1.4 and always warms up within a mile or two even in cold weather, after which the needle never budges ( as expected from the design described above).  I would suspect a thermostat that isn't fully closing.

[vRS G60]

18 hours ago, Urrell said:

Looks like there are 2, one on the main circuit which I take is the block and the other on the head.
None easy but it sounds like your heater is working so the head one should be OK.
This shows the main circuit thermostat and there is a bit of dismantling before even getting to here.

 

 

 

Thanks for that, however the only part I can find when I do a search for a 1.2 TSI thermostat is this type. No one list a thermostat in the coolant pump housing!!!!

 

 

[Urrell]

Could that be a difference between the earlier and later 1.2 engine?

[vRS G60]

Possibly, that's what I was thinking.

[voxmagna]

Before launching into buying and replacing parts why not hang diagnostics on and see what's going on? You need to look at the engine cyl. head temperature sensor readout and the coolant temperature. Without diagnostics you can drive 4 or 5 miles from a cold start then quickly feel around the radiator and hoses. If they are warming up, then the stat is open when it should still be closed! When the cooling system works normally starting from cold, coolant should only be circulating around the block and head in 'bypass'.  As the coolant in the jacket warms up, the stat starts to open and is fully open when your dash gauge settles at normal. Diagnostics should show the engine temperature rising more rapidly than dash gauge temperature. If both are rising at the same rate, then your thermostat is open when it should be closed! If both temperatures are similar and stay cold, then your thermostat is closed and heat losses (although unlikely) from the heater matrix and engine are most likely causes. Making sure the temperature controls are working correctly is important, because the engine uses them to set the fueling rich for cold weather. The quicker you get warm up the better will be fuel economy.

 

When it is extremely cold and a vehicle has been left parked outside overnight, the cylinder head and block will be very cold. Added to that will be the cold rush of air coming through the radiator and passing over the engine, so it will take longer to warm up. That is the one reason why a radiator blind or partial covering of the front grill with cardboard (cheaper) in winter can help get faster warm up for short commute journeys. But you have to remember to remove it in Spring!

[Ryeman]

The old ‘hand on the hose’ costs nothing too.

However, I’m not sure if their aren’t cars with the thermostat down on the bottom hose these days .

Edited 10 January, 2018 by Ryeman

[voxmagna]

1 hour ago, Ryeman said:

The old ‘hand on the hose’ costs nothing too.

However, I’m not sure if their aren’t cars with the thermostat down on the bottom hose these days .

 

That's often where they are, but you often need to remove the engine tray first and for me it's a lot easier to plug in vcds vagcom.  Some of the new stats have got really clever now, but I don't know if the Skoda stats are (clever). 

 

The regular way of doing bypass is the stat is fully closed and holds back coolant from the rad. so it only circulates around the restricted bypass loop - the block and cyl. head. As the stat. opens, the easier flow route is then through the radiator. But the bypass loop is still open and some cooling efficiency from the rads is lost, particularly when stalled in heavy traffic and water pump speed is low.

 

And so somebody came up with the smart solution: Build a bypass flap valve into the stat. and add a port to the hose plumbing. When the stat is fully closed the bypass loop gets all the coolant. When the stat is fully open, it pulls a second flap closed to shut off the bypass loop completely and all the coolant then flows through the radiator without loss of efficiency. In stalled traffic with idle pump speeds, all the coolant is going where it should and no flow is lost around the bypass loop.

.

Edited 10 January, 2018 by voxmagna

[Ryeman]

1 minute ago, voxmagna said:

 

That's often where they are, but you often need to remove the engine tray first and for me it's a lot easier to plug in vcds vagcom.  Some of the new stats have got really clever now, but I don't know if the Skoda stats are (clever). 

 

The regular way of doing bypass is the stat is fully closed and holds back coolant from the rad. so it only circulates around the restricted bypass loop - the block and cyl. head. As the stat. opens, the easier flow route is then through the radiator. But the bypass loop is still open and some cooling efficiency from the rads is lost, particularly when stalled in heavy traffic and water pump speed is low.

 

And so somebody came up with the smart solution: Build a bypass flap valve into the stat. and add a port to the hose plumbing. When the stat is fully closed the bypass loop gets all the coolant. When the stat is fully open, it pulls a second flap closed to shut off the bypass loop completely and all the coolant then flows through the radiator without loss of efficiency. In stalled traffic with idle pump speeds, all the coolant is going where it should and no flow is lost around the bypass loop.

.

....plus on demand electric pumps it seems.

Its becoming simply tech overload , making the ICE even more dubious as a long term, worry free, proposition.

I long for the MGB motor’s simplicity .....long gone.

[Ryeman]

I was reading about a problem with the auto close feature on a Jeep, and the solution was to start with a software update.

That fixed it.

How long before a software update fixes a cooling problem, I wonder.

[Urrell]

I would think the small coolant circuit thermostat is OK as the heater is working and would probably be easier to feel for heat in the hoses from that one rather than the large circuit thermostat near the water pump.

[vRS G60]

I have no access to any diagnostics so I'll feel at the hoses.