Cooling a 2.0 16v - rad fan (new switch fitted..)

[davidwort 0]

bummer, I bet you're sick and tired of draining coolant, I don't know what it is with old valver cooling systems, I changed bally's stat to a VAG one and even though it opened and closed almost identically with the new pattern one he had fitted(heating in a pan of water), there was a noticable change in the engine temp when we put the VAG one in.

I don't think the wiring and dash clusters help, they seem to contribute to some funny gauge behaviour when they get old too, possibly the voltage regulator on the dash.

[Jim 1]

Mind you, it's pretty cold out, so the rad temp should be held fairly low while driving. Did you ever use Eric's thermometer?

 

Well when actually driving the temps stay nice and low. So I gave it some welly for a few minutes then pulled up at the side of the road and let the temps climb (and climb) - coolant hit around 110 degrees as usual with no sign of the fan budging so I just gave up and drove off again.

 

bummer, I bet you're sick and tired of draining coolant, I don't know what it is with old valver cooling systems, I changed bally's stat to a VAG one and even though it opened and closed almost identically with the new pattern one he had fitted(heating in a pan of water), there was a noticable change in the engine temp when we put the VAG one in.

 

Well its a Stealth fitted one in there at the minute so it'll be GSF. I promise as long as I own Corrado's, I'll never ever fit another pattern part to my car again if a new genuine thermostat cures it. The pattern GSF belts I have on my car are currently making all sorts of whirring and squeaking noises, and don't even get me started on their fecking wheel bearings. I'll go to Stealth with genuine parts and get them to fit them from now on!!

 

possibly the voltage regulator on the dash.

 

Been meaning to change this for some time but was a bit afraid of getting the clocks out and breaking plastic trim seeing as the car has done so many miles (expecting stuff to be brittle) but might do it sooner rather than later..

[Toad 0]

My Ex-Housemate's Jetta GTI used to blow all the coolant out with distressing regularity, I swapped the stat for a genuine VAG one, and while they seemed to work similarly in the saucepan, it seemed to sort the issue out straightaway.

[Toad 0]

The pattern GSF belts I have on my car are currently making all sorts of whirring and squeaking noises.

 

Mine makes a very funny noise from cold (don't think it was too bad when you were with me) but it's the idler on the water pump pully being knackered. Really need to get round to welding it on solidly.

[Supercharged 2]

idler on the water pump pully being knackered. Really need to get round to welding it on solidly.

 

Get a pulley off a later car of MK3 mate - thats a well known issue with the KR engine...

 

Jim - Yeah change the stat mate, if this isn't working spot on then nothing else will as the whole system is designed and regulated by this component...

[Toad 0]

idler on the water pump pully being knackered. Really need to get round to welding it on solidly.

 

Get a pulley off a later car of MK3 mate - thats a well known issue with the KR engine...

 

 

Yeah I know about those, but I'm a pikey and don't want to spend the money. ;)

[Jim 1]

The pattern GSF belts I have on my car are currently making all sorts of whirring and squeaking noises.

 

Mine makes a very funny noise from cold (don't think it was too bad when you were with me) but it's the idler on the water pump pully being knackered. Really need to get round to welding it on solidly.

 

Is it like a metallic squeaking / buzzing noise from 2,000RPM up to about 3,000RPM? Mine's recently taken to making a similar noise and I was at a loss to explain it. I was going to blame the cat heatshield which seems to unweld itself around once every year and makes bizarre noises like that, but would be interested to know if the 9A and the KR share the same idler pully design!

[keithabc216v 0]

looking at the haynes manual for the passat with kr & 9a it just

says dohc engine so would think they are the same

[davidwort 0]

the idler pulley on the waterpump on a KR (up to early 1991 chassis no. 50-M-009000) is unique to the 1.8 KR and is needed becasue the alternator drive belt needs to be deflected around the waterpump.

The late KR blocks (1991 cars) have the same setup as the 9A, where the PAS pulley is driven by a belt dedicated to the PAS and doesn't drive the waterpump as on the earlier design, this means one belt can drive the alternator and waterpump without the need for an idler pulley.

It's not as easy as just swapping a couple of pulleys though, the 9A engine has a crank pulley for the PAS which is different and a PAS pump with a longer driveshaft (distance from pump body to pulley).

 

If the KR idler pulley is worn it tends to chatter at idle and the outer part is quite wobbly. The slip surface/bearing thing tends to break up into pieces. I've seen a few welded up as Toad says, and I guess it doesn't generally cause much of a problem, although I'd imagine the belt would wear quicker as it'll have to slip on the pulleys a small amount.

[G Charged 0]

my g60 has been similar to yours...just runs too hot for my liking....so at the moment i have a switch in my glovebox which i turn on and off myself..

 

been looking at the neuspeed lower temp rad switch from awesome...im going to try that and see if it fixes my problems

 

 

also out of curiousity, are you sure your alternator is charging properly?..you may have a voltage drop which is why the fan wont spin as fast/not spin at all...im sure i read all early corrados are suspect of doing this...

[Jim 1]

I'm fairly sure my alternator is charging OK - I never have a lack of power to crank the car even after a week or more of it standing around.

 

Just bumping this up as I'm going to have to get onto sorting this out.. was slightly alarmed earlier sitting in traffic (had only been there 5 minutes!) to notice the oil temperature at 118 centigrade! In this weather?! Jeyzus! Had a bit of a panic and thankfully the traffic moved and the airflow helped get the temperature back down again quickly.

 

So - for those that were helping with this, I don't remeber where we got to? I was going to look at changing the thermostat, right? :)

[davidwort 0]

yup, it's thermostat time definitely,

in this weather it will be closing up when you're on the move as the air is chilling that engine down pretty quickly, once you stop or slow the temp will pick up and the stat opens more fully again, so it will be moving open and shut (or partially) a fair bit in this weather and if it's not quite operating right then your symptoms would be worse

with the symptoms you've had before and what's going on now, it must be the stat, but 118 oil isn't a big problem, don't forget the manual says back off when it reaches 145 :lol:

[Jim 1]

Last time I ever allow a GSF piece of kit to be fitted to my car EVER again. Cheers davidwort - you've been super patient analysing this problem and giving me useful answers!

 

And it wasn't so much the temperature mate but how quickly it got there. I toddled into town in light traffic, and just stopped at a junction and before I knew it the oil was there and the coolant was at 110 centigrade.. the car had only been running for 30 minutes max! And again as soon as I set off down the road the temperature plummeted - could almost watch the gauge falling if I watched it.

[Jim 1]

Ok - had it in to Stealth today for a service so let them do the thermostat. Got a brand new VAG one. Car warms up a lot quicker (like matter of minutes) but interestingly it's still running warm. Just on the 20 minute drive back from Stealth in light traffic the coolant temp was up to 110 centigrade and the engine oil was up to 120 degrees. I don't get it. I'm sure it's not supposed to run this warm, especially in comparatively cool weather and untaxing conditions.. I frankly don't know where to go from here :(

[RDH 0]

No help I'm afraid Jim, but mine does exactly the same, this was following a top end rebuild when I had the water pump and stat replaced (pattern parts), my next step will be OEM parts. Will let you know if I sort it.

 

Rich

[Jim 1]

Have to admit I'm debating getting a Mocal fitted.. should help wrestle oil temps back into the right sort of place but would rather know what the exact cause is!

 

Interestingly the fan did briefly come on but went off again just before putting the car away - it really is as though the temp sender that feeds the temp display on the dash is incorrect. If the coolant was as hot as it reckons, the radiator fan should be on. I'm really tempted to buy another just to rule it out as its such an easy swap, and a relatively cheap part.

[keithabc216v 0]

or the dash its self reading wrong ?

[Walesy 0]

Ok - had it in to Stealth today for a service so let them do the thermostat. Got a brand new VAG one. Car warms up a lot quicker (like matter of minutes) but interestingly it's still running warm. Just on the 20 minute drive back from Stealth in light traffic the coolant temp was up to 110 centigrade and the engine oil was up to 120 degrees. I don't get it. I'm sure it's not supposed to run this warm, especially in comparatively cool weather and untaxing conditions.. I frankly don't know where to go from here :(

 

I've not read the rest of the thread, but if you haven't already done it - change the rad, i've had a few that have not overheated but just run hot and only changing the rad has cured it :)

[Henny 0]

Ok - had it in to Stealth today for a service so let them do the thermostat. Got a brand new VAG one. Car warms up a lot quicker (like matter of minutes) but interestingly it's still running warm. Just on the 20 minute drive back from Stealth in light traffic the coolant temp was up to 110 centigrade and the engine oil was up to 120 degrees. I don't get it. I'm sure it's not supposed to run this warm, especially in comparatively cool weather and untaxing conditions.. I frankly don't know where to go from here :(

 

I've not read the rest of the thread, but if you haven't already done it - change the rad, i've had a few that have not overheated but just run hot and only changing the rad has cured it :)

 

Exactly my thoughts there Walesy... I've just read the last page of this thread (trying to catch up on 2 years of posts!) and that was the first thing that jumped to my mind - blocked/furred up radiator... :|

[davidwort 0]

he's got a new VW rad on it :?

worth flushing through with a hose to make sure though?

[mrbeige 0]

Jim, have you tried cleaning the pins on the sensor connectors? It could be your sesnors giving you a false reading??

[KipVR 1]

Just seen the thread, I think it could possibly be a water pump problem, how many miles has it done? If the pump is not pumping enough water through, then there will be a big heat differential between the water in the rad where the fan switch is and the water at the top of the head where your temp sender is for the MAF.

[Jim 1]

The water pump is about a year and a half old. Though I bought it from Supercharged - he assured me it was new / refurb VW item and I do trust him but not sure where else to look!

[Jim 1]

I've not read the rest of the thread, but if you haven't already done it - change the rad, i've had a few that have not overheated but just run hot and only changing the rad has cured it :)

 

It's a new genuine VW (Denso) radiator mate - no more than a year old :(

[Jim 1]

I've not read the rest of the thread, but if you haven't already done it - change the rad, i've had a few that have not overheated but just run hot and only changing the rad has cured it :)

 

It's a new genuine VW (Denso) radiator mate - no more than a year old :(

 

Will just do an update list now of everything that has been replaced within the last 2 years so I can take stock of where I'm at!

 

Genuine VW Rad

Genuine VW Thermostat

Expansion Tank

Expansion tank pipe from top of radiator

The two coolant pipes at the top and bottom of radiator

Genuine VW water pump

Genuine VW ECU Coolant temperature sensor

Genuine VW radiator fan / temp switch (changed 3 times)

Genuine VW dash temperature sender

2nd hand fan controller module (lives in front of the expansion tank)

 

Water pump seems plausible. The water temp gets up WAY quicker than the oil temperature does..

 

Possible I have a blocked water way somewhere? Worth changing the oil cooler..?!