Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length

[Nick W]

So just for my understanding, with engine at normal temp and everything as it should be. You would not expect to see pressure changes in coolant system under RPM changes?

I'll pop the stat off at the weekend, pop it in some boiling water. I take it I will see the coiled part retract slightly? If nothing then it's stuck shut?

I guess that would give the same symptoms? - Coolant in the engine block gets too hot, the stat refuses to open, thus not allowing colder coolant in from the rad into the block?

The pump is for coolant flow. Pressure comes from the coolant heating up in a sealed system.


Your symptoms are a flow issue. Whether that is caused by a blockage(and a faulty thermostat is  the usual cause) or a defective waterpump can only be confirmed by actually checking the car. One of these  http://www.ebay.co.uk/itm/Handheld-Digital-LCD-Temperature-Thermometer-Laser-Non-Contact-IR-Infrared-Gun-/361435030500? hash=item542734e3e4:g:A4YAAOSwosFUXKVK is an efficient way of checking the flow, as you can easily track the temperature of various parts of the cooling system. £11 is dirt cheap for a tool you'll find allsorts of uses for; blocked exhausts, bad wheelbearings, seized brakes, central heating faults are all easily diagnosed and the laser makes a good cat toy.
I think you have a loose impeller on the waterpump, a fault that is becoming increasingly common.

[Andy H]

So just for my understanding, with engine at normal temp and everything as it should be. You would not expect to see pressure changes in coolant system under RPM changes?

I'll pop the stat off at the weekend, pop it in some boiling water. I take it I will see the coiled part retract slightly? If nothing then it's stuck shut?

I guess that would give the same symptoms? - Coolant in the engine block gets too hot, the stat refuses to open, thus not allowing colder coolant in from the rad into the block?

If a thermostat is going to stick shut then it will normally do it from cold.

Have you inspected the pump yet?

[Sir Tigger KC]

I'd flush the rad before dismantling stuff, especially as you need to disturb the cam belt. 

[zirk]

One of these

http://www.ebay.co.uk/itm/Handheld-Digital-LCD-Temperature-Thermometer-Laser-Non-Contact-IR-Infrared-Gun-/361435030500?hash=item542734e3e4:g:A4YAAOSwosFUXKVK
 

Dont tell Him to buy one of them, for Gods sake, He be playing with for weeks, He be posting up all sorts of issues, heated seat temp, wing mirror temp, inner ear temp, LPG tank temp, the list will be endless.   

[Nick W]

One of these

http://www.ebay.co.uk/itm/Handheld-Digital-LCD-Temperature-Thermometer-Laser-Non-Contact-IR-Infrared-Gun-/361435030500?hash=item542734e3e4:g:A4YAAOSwosFUXKVK
 

Dont tell Him to buy one of them, for Gods sake, He be playing with for weeks, He be posting up all sorts of issues, heated seat temp, wing mirror temp, inner ear temp, LPG tank temp, the list will be endless. 

You've got one too

[zirk]

One of these

http://www.ebay.co.uk/itm/Handheld-Digital-LCD-Temperature-Thermometer-Laser-Non-Contact-IR-Infrared-Gun-/361435030500?hash=item542734e3e4:g:A4YAAOSwosFUXKVK
 

Dont tell Him to buy one of them, for Gods sake, He be playing with for weeks, He be posting up all sorts of issues, heated seat temp, wing mirror temp, inner ear temp, LPG tank temp, the list will be endless. 

You've got one too

No, but as Trigger say's on 'Only Fools and Horses' "Im thinking of getting one though" 

So, why that one Nick, and not one of the cheaper 5/6 quid ones?, or was that an example on ebay.

[tunnie]

Firstly, thanks for everyone's comments OOF at its best 

Cheaper one here:http://m.ebay.co.uk/itm/Handheld-Digital-LCD-Temperature-Thermometer-Laser-Non-Contact-IR-Infrared-BIT-/121858599675?nav=SEARCH

Is Nicks one better quality? Also thanks for suggesting. Looks very useful, will get one of these 

[zirk]

Firstly, thanks for everyone's comments OOF at its best 

Cheaper one here:http://m.ebay.co.uk/itm/Handheld-Digital-LCD-Temperature-Thermometer-Laser-Non-Contact-IR-Infrared-BIT-/121858599675?nav=SEARCH

Is Nicks one better quality? Also thanks for suggesting. Looks very useful, will get one of these 

See, I toid ya, we'll never going to hear the end of it now.   

[Nick W]

One of these

http://www.ebay.co.uk/itm/Handheld-Digital-LCD-Temperature-Thermometer-Laser-Non-Contact-IR-Infrared-Gun-/361435030500?hash=item542734e3e4:g:A4YAAOSwosFUXKVK
 

Dont tell Him to buy one of them, for Gods sake, He be playing with for weeks, He be posting up all sorts of issues, heated seat temp, wing mirror temp, inner ear temp, LPG tank temp, the list will be endless. 

You've got one too

No, but as Trigger says on 'Only Fools and Horses' "I'm thinking of getting one though" 

So, why that one Nick, and not one of the cheaper 5/6 quid ones?, or was that an example on ebay.

Delivery times, it's in the UK, the cheaper ones are sent from China.


Mine's Bluepoint, bought off the Snap-On van at least 13 years ago for £30. Which was half the price of the next cheapest I'd seen  at the time. Now, I'd buy a cheap one, as I only use it for diagnostics and that's comparative rather than accurate.

[tunnie]

Ah yes. Point taken, much quicker delivery. 

[tunnie]

Much to Zirk's disappointment, I've just ordered one Nick linked to 

Thoughts and actions so far:

 - Sub 25mph, with low RPM, temp stays stable. Higher speed = higher temps, also low speed but under load (ie climbing a hill) also increases temp.
 - Cooling fan even at 95c is not coming on. However it's been shorted out as a test, it spins up fine. 
 - Engine starts and runs well, no miss-fires, it also runs fine on either LPG or Petrol.
 - Cabin Heat is good.

1) Next test I will get to do is putting the stat in boiling water, see if it opens.

2) One test would be to use new thermometer to see how hot rad is when fully warmed up, is it failing to trigger fan?  That said higher speeds would keep temp down I would have thought, which is not the case.

3) Take cam cover off, so that the new thermometer could get a reading off the water pump.

4) Get a temp reading on the LPG vap.

Any other thoughts?

[Nick W]

Much to Zirk's disappointment, I've just ordered one Nick linked to 

Thoughts and actions so far:

 - Sub 25mph, with low RPM, temp stays stable. Higher speed = higher temps, also low speed but under load (ie climbing a hill) also increases temp.
 - Cooling fan even at 95c is not coming on. However it's been shorted out as a test, it spins up fine. 
 - Engine starts and runs well, no miss-fires, it also runs fine on either LPG or Petrol.
 - Cabin Heat is good.

1) Next test I will get to do is putting the stat in boiling water, see if it opens.

2) One test would be to use new thermometer to see how hot rad is when fully warmed up, is it failing to trigger fan?  That said higher speeds would keep temp down I would have thought, which is not the case.

3) Take cam cover off, so that the new thermometer could get a reading off the water pump.

4) Get a temp reading on the LPG vap.

Any other thoughts?

Low speed/low RPM doesn't put much heat into the system; just look at how long it takes to open the thermostat when idling.


Cooling fan not coming on at indicated 95* suggests that the sensors are seeing different temps, and they are as far apart as they can be. Likely cause: poor coolant flow


Starts and runs well means it's unlikely to be a serious mechanical fault(head gasket, cracked head etc). You would have mentioned water loss, which is either a visible leak or going out the exhaust/into the oil.


I would normally just replace a thermostat due to its low cost but you've already done so a that, so simple testing is justified.


Use the thermometer to check all accessible parts of the cooling system; hoses, water pump, housings, heater hoses, outlets, various points across the radiator(you might be surprised how a healthy one will measure). This is just a more sophisticated way of feeling the radiator hose for the 'stat to open.


I still think you've got a defective waterpump

[tunnie]

Thanks 

Stat is very new, but just an ECP one, so who knows how well these last. But I would have thought better than weeks!

Still, testing the stat is dead easy and easily accessible on the 2.2. So a nice quick test before disturbing the cambelt.

[TheBoy]

I'd check pump at same time. Quick and easy on 2.2.

You could have both checked in under an hour (double if nursing a Friday night indulgance)