HELP - Over heating issues since intercooler fitment

[MickeyT 0]

Since fitting my FM intercooler I've been having very high oil and water temps, this has culminated with it overheating on the motorway the other day and pissing out coolant :( (guessing the pressure got too much as I was in traffic) But the temps were hot even when cruising at 70.

 

Managed to get home but trying to figure out the probs. Done a search and it appears to be one or a combination of the below:

 

An air lock: I will flush out the system and replace coolant via top hose.

 

The fan doesn't seem to work or only very slowly (can be stopped easily by a finger!) I think the connector on the plug in the centre motor have gone so I will replace with 'slip on' connectors. Could it be anything else??

 

The rad gets warm and so does the top hose but the bottom hose stays cool - Does this mean the thermostat has gone?

 

Gotta get this sorted as I'm car less, :evil:

 

Cheers guys!

[Riley 0]

The rad gets warm and so does the top hose but the bottom hose stays cool !

 

sounds like air in the system to me.

 

i always have the car running without expansion cap on.

 

while squeezing the bottom hose,you should see any air bubble up into the expansion tank.(carefull of any moving parts!)

 

edit:leave it ticking over for a while to get upto temp,keep an eye on the gauge,then after leaving it for a while(turned off) slowly and carefully remove the cap and let the level settle,then top up as required.

 

also the temp switch for the fan will not read properly if its sat in air rather than water.

 

neil. :)

[h100vw 0]

Fan motor could be forked. Jump the rad switch with a paper clip or a piece of wire.

 

I wouldn't poke a finger in the fan on my Syncro without an ambulance present. :mrgreen:

 

Like Riley I fill up the cooling system with the engine running and cap off. Never had problems yet with airlocks.

 

Gavin

[MickeyT 0]

Fan motor could be forked. Jump the rad switch with a paper clip or a piece of wire.

 

Is that literally taking off the plug with the ignition turned on and making a connection between two of the three terminals on the fan motor?

[h100vw 0]

Yeah, if I remember right there is a red straight off the battery in the plug. Jump that to either of the others. One wire is low speed the other high.

 

OBVIOUSLY don't be surprised when it sparks a bit. :mrgreen: It won't take your hand off.

 

Gavin

[MickeyT 0]

Cheers Gavin I'll give it a go!

[h100vw 0]

Just re-read the first post. Cold bottom hose is not good. At tickover with no airflow I would expect the top and bottom hoses to be pretty much the same temp.

It could be a jammed thermostat.

GAvin

[MickeyT 0]

No luck when putting something across the fan terminals - Buggered fan motor as well then??

[h100vw 0]

Did you try all combinations of teh 3 wires?

[MickeyT 0]

Right I've got a speed on one of them (far terminal from live) but not the other (middle terminal) even thats not exactly fast!!

[h100vw 0]

Sounds like the fan is gone then.

 

Do you have a volt meter just to confirm that power is going to both the terminals at the motor and proving that it's not a wiring issue.

 

I have a couple of serviceable fans in the garage, having had one die on me I keep them on the shelf.

 

Gavin

[MickeyT 0]

Yeah looks like the fan is knackered. Got a reading of 12 across the battery terminals as a test but nothing across any of the fan connectors

[gradeAfailure 0]

If the bottom rad hose is staying cool then it could well be a stat issue - personally, I'd run one of the Neuspeed 180deg stats from AwesomeGTI, they're well worth it...

 

Alternatively, if you just want a std replacement VW one, then I've got a brand new one you can have for a few pannies...

[g60bv 0]

aren't those stats just diesel ones. ? the low temp fan stat is, but the thermostat my also be the diesel one ?

[gradeAfailure 0]

I have no idea, but it did have "Neuspeed" stamped on it IIRC! :)

[MickeyT 0]

Just ordered one of the Neuspeed stats. Guessing it must be the stat as when the rad was hot the bottom hose was still stone cold.

 

Are they easy enough to remove??

[Guest]

MickeyT, before you start creating sparks mate.. to test the fan easiest way is the pull the spade off the temp sender above fuel rail and then earth the spade to inlet by holding it. that will trigger your fan. if it doesn't its gone, whether it be fuse etc.

[fla 9]

G60Dub, you just wanted to show off you engine bay! Very nice though, well done m8. And yes, I am jealous.

[Guest]

lol.. its not that clean at the minute, but yeh i did wanna show it off hehe

[Henny 0]

when I did my conversion on J-DUB I found I had the same problem as you're describing... turns out that the wiring to the fan was only getting 9V under load (shows 12V on a multimeter when disconnected though!) I made up a loom similar to one of Gav's headlamp looms to stick in a nice fat power supply to the fan and haven't had any problems since... 8)

 

Also, you don't want to be shorting out the connector onto the FAN, you want to be shorting out the connector onto the radiator switch! I'm hoping you've just typed that wrong else you've almost certainly blown the fuse by now! :|

[MickeyT 0]

Well I've checked all the relevant fuses in the fuse box and earthed the temp sender as suggested by G60Dub. No joy. I guess this suggests the fan itself is fooked.

 

Is it worth buying an aftermarket jobbie (eg Pacet) instead of the oe fan. I think they work out about the same price. Got any recommendations??

[Henny 0]

I bought a 12" one (DCSL 12) from Think-Auto and it's knocked the running temps RIGHT down... it's also a shed load smaller thickness than the original one and tidies the bay up LOTS... 8)

 

It's only a single speed, so I've wired it up via a relay to come on flat out as soon as the low temp comes on, although I may re-wire it soon via a large resistor to give me the 2 speeds again... 8) I didn't bother with their relay kits, I just used a normal 15A relay from a local motorfactors and the original radiator thermo switch which kept the costs down lots... ;)

[MickeyT 0]

Sounds good Henny, do you know of any that come as complete kits or are a simple fit using the original wires as electrics isn't my forte!!

[Henny 0]

if you can't be arsed to put in a relay, you don't have to... ;)

 

All you need to do is to put on 2 male spade terminals onto the wires to the new fan and plug it into the original fan connector, one into the earth and the other into the wire which is the +ve for the low speed. This will mean that your fan will come on flat out as soon as the low speed trigger temp is reached, and will stay on until it goes below that temp again... 8)

Easy as pie... 8)

 

Mounting it is a little more tricky... I used some metal holed strips (looks like meccano!) and cable ties to hold mine in place with the ends of the strips held onto the radiator by the original 4 screws which held on the old fan shroud... Sounds a little like a bodge, but is actually very sturdy, allows some flexibility, and, if done nicely, looks good too... ;) 8)

[MickeyT 0]

Cheers Henny - Think I'll have a look at those fans