M@tt 77 Posted August 1, 2008 (edited) Right well my GTI6 conversion has behaved pretty much flawlessly so far however i've noticed that the coolant temp gets VERY hot if in traffic for any period of time it its right up to where the red light is but without the redlight coming on. One thing i need to fix is that i've blanked off one of the outlets on my expansion tank but used a bit of walking stick and this is fizzing and bubbling once the coolant gets up to temperature. I'm wondering if this is causing the coolant system to not maintain pressure properly and therefore get overly hot. The fan does kick in but i dont think at the lower level only full speed so that resistor could do with changing. Obvioulsy the first port of call is to get something to properly blank off that expansion cap outlet but i'm not overly convinced that will cure it. I've had a good go at bleeding the system so i dont think its got an airlock but could be wrong. Anyone else experience this at all? Matt Edited August 1, 2008 by M@tt Share this post Link to post Share on other sites
Alastairh 47 Posted August 1, 2008 Night mare! If you have problems tracking down a blank, let me know mate How good is your rad, any signs of head gasket? Al Share this post Link to post Share on other sites
NeilGTi85 5 Posted August 1, 2008 (edited) Right well my GTI6 conversion has behaved pretty much flawlessly so far however i've noticed that the coolant temp gets VERY hot if in traffic for any period of time it its right up to where the red light is but without the redlight coming on. One thing i need to fix is that i've blanked off one of the outlets on my expansion tank but used a bit of walking stick and this is fizzing and bubbling once the coolant gets up to temperature. I'm wondering if this is causing the coolant system to not maintain pressure properly and therefore get overly hot. The fan does kick in but i dont think at the lower level only full speed so that resistor could do with changing. Obvioulsy the first port of call is to get something to properly blank off that expansion cap outlet but i'm not overly convinced that will cure it. I've had a good go at bleeding the system so i dont think its got an airlock but could be wrong. Anyone else experience this at all? Matt I have exactly the same problem at the mo except that the outlet on my expansion tank is blocked with a socket of some sort but it does not leak. I have found that when im stuck in traffic if i put the blower on full blast it levels the temp......but thats just a way to avoid it Im going to buy some water weter (redline) which changes the properties of the water and makes it flow faster round the system.....There was a thread somewhere about it, ill try and find it Neil Edit - This is the stuff ( http://www.opieoils.co.uk/p-1035-redline-w...er-coolant.aspx ) could not find the thread about it though... Edited August 1, 2008 by NeilGTi85 Share this post Link to post Share on other sites
Garry 1 Posted August 1, 2008 Mine does the same. I don't think it is your blanking as that is what you have to do anyway. If you look at my build thread I use a socket extension! I find it runs OK in normal driving and when sat idling, the problem occurs during crawling in traffic when some revs are required. The fan kicks in but very late, I think its at the last notch or so. This weekend I will be fitting a manual overide switch for traffic use, the fan can control the heat, it just comes on too late, I didn't want to fit a lower temp fan switch as when on track and the temperature does start to rise I didn't want it kicking in too early. The other thing to consider is how accurate the actual gauge is? Also, which header tank cap are you running? I used to find that my old 1.9 cap used to allow coolant to blow out as the spring wasn't strong enough. I now use a 306 xsi cap which seems to have solved the problem. Share this post Link to post Share on other sites
pj838 0 Posted August 1, 2008 Mine doesn't like traffic either, if sitting for a while it is getting on for the red - most time it is sat about vertical driving normally. I have the gti6 oil cooler setup as it was and a new ali 205 radiator. But as you say these gauges are not exactly the most accurate... Share this post Link to post Share on other sites
welshpug 1,657 Posted August 1, 2008 (edited) I wouldn't say that they are inaccurate, more that the scale isn't that appropriate for an engine that runs warmer than the original alloy block 8 valver. Here's a picture of the gauge from the Handbook that has the figures on the dials, had to tidy it up with the editor to make it clearer. IIRC the fans come on full circa 100 degrees, so seeing the needle near the top of the gauge wouldn't worry me. Edited August 1, 2008 by welshpug Share this post Link to post Share on other sites
kate205gti 4 Posted August 1, 2008 same here - ive got a manual switch wired in though so click it to low level as soon as i stop then max level if im sitting for more than 5 mins and it levels just be wary about letting it out of your sight in tyre places (or switch it on before you let them touch it!) Share this post Link to post Share on other sites
Matt Holley 11 Posted August 1, 2008 I had this problem, I have since fitted a new nissens rad and done away with the oil/ water cooler, its alot better now. Share this post Link to post Share on other sites
NeilGTi85 5 Posted August 1, 2008 I had this problem, I have since fitted a new nissens rad and done away with the oil/ water cooler, its alot better now. Have you got a link to where you got this? Cheers Neil Share this post Link to post Share on other sites
M@tt 77 Posted August 1, 2008 My only concern with the blanking is that i'm using a bit of wood and water/coolant is able to bubble boil through it but i havent been able to find anything as yet suitbale for blocking it off Yep when i'm driving normal the levels are absolutley fine, sits vertically on guage (4th bar) but in crawling traffic the temp really starts to climb. i'm using an uprated expansion cap (306 one) so its definitely not blowing past that. I'm using the standard 306 temp sensors though so i wonder if perrhaps its a different resistance to the 205 one that the dials are expecting and therefore reading differently?? Share this post Link to post Share on other sites
welshpug 1,657 Posted August 1, 2008 4th bar = 90, as shown above about right for the normal running temperature of these. Share this post Link to post Share on other sites
Miles 331 1 Cars Posted August 1, 2008 Be careful with the Cap, When Garry did this his top hose expanded to the size of well, Busting point as the pressure was just too much, For a blanking plug you can use a bit of solid round bar from B&Q etc Share this post Link to post Share on other sites
Alastairh 47 Posted August 1, 2008 (edited) Aren't you running a cooler thermostat? Personally id be tempted to do away with the Oil and water cooler. It never worked that well on my old GTi6, but works well on my current mi. Al Edited August 1, 2008 by Alastairh Share this post Link to post Share on other sites
James_R 3 Posted August 1, 2008 to start off I'd chop the ballast resistor out the fan circuit so it just comes straight on full blast rather than the mincey does bugger all slow speed setting, works a treat and no need for these stupid manual overide swtiches, they're far too heavy!! the Gti-6's in std 306's do go almost off the scale before the fan kicks in, (scares you the first time) as they gain soo much heat before the fan comes on, worth baring in mind that's normal. Personally I've dumped the std water pump and gone for a better control system, but that's a bit extreme and not really an everyday car solution Share this post Link to post Share on other sites
