gundersen Posted June 22, 2012 Author Share Posted June 22, 2012 All temperatures where read on the same Caterham gauge, so let's hope that it is just that Link to comment Share on other sites More sharing options...
patneale Posted June 22, 2012 Share Posted June 22, 2012 I have 140 bhp K series in SV body and I had a hot K series as well.( No track work) After a 70MPH run the fan was always running and temp nearly 100. I figured out that it was because the larger nose cone left a big gap around the sides of the radiator. The cooling air obviously will go around the radiator rather than through it as there is less resistance. I made up some aluminium plates ( from B and Q ) to close off the gaps and used the radiator bolts to attach. so almost all the air coming through the grill has to go through the radiator. Problem solved, but I have also had a new radiator as I wrecked the fins of the old one with a pressure washer (Take note, don't use a pressure washer to clean the radiator) I think that the new radiator is more efficient. When I went to Minister Racing engines some years ago , they always fit a lower temperature thermostat than the standard 88C one that is fitted. I tried this, but the heater was too feeble on a cold day. All is well with mine since the plates were fitted. Suggest you also fit a heat shield around the alternator near the exhaust with the spare aluminium you will have over. I ruined the rear bearing due to overheating. I fixed mine with hose clips around the engine mounting leg and while you are in the mood a little shield over the starter assembly attached to a convenient bolt will save that from overheating from the exhaust as well. Dear old Jez Coates at CC was so obsessed with weight that he was horrified at my changes..." just think of the weight" he said..... "Yes at least 2 Mars bars" I replied ! Link to comment Share on other sites More sharing options...
Titanium7 Posted June 22, 2012 Share Posted June 22, 2012 This didn't start after you fitted your silicone hoses did it? I only say that because it happened to me and in the end the only way to solve it permanently was fitting a PRRT system. here Link to comment Share on other sites More sharing options...
gundersen Posted June 22, 2012 Author Share Posted June 22, 2012 Quoting Myles: I changed to a Caterham triple-pass rad a few years back...Thank you for the warning, it seems that the triple-pass is getting less than stellar reviews on here. So any change in radiator will probably be to a radtech. Quoting Johnty Lyons: Are you sure your Rad core is completely clean/clearWell I am not much of a polisher, but it seems to be resonably clear core1 core2 fan Quoting John Vine: Presumably you're measuring the oil temp using the sender in the Apollo? Are you reading oil and water temps on the same gauge (using a two-way switch)?Oil temp is read by sender in apollo, and I am using a two-way switch on the same gauge to view the temperatures. However, the gauge agrees very well with the temp reported by the ECU through the OBD interface Quoting patneale: The cooling air obviously will go around the radiator rather than through it as there is less resistance. I made up some aluminium plates ( from B and Q ) to close off the gapsThis sounds very resonable and would explain the less effective cooling. Thank you for the tip! Quoting Titanium7: This didn't start after you fitted your silicone hoses did it?Nope, first track day was with the old hoses. Otherwise it would have been a good bet that I screwed something up installing them Quoting Titanium7: I only say that because it happened to me and in the end the only way to solve it permanently was fitting a PRRT system.I have been looking at the PRRT, and I really like the idea behind it. So I might just end up installing one (thanks for the pics), but seeing as my setup should be able to provide sufficient cooling as it, I would like to find any errors in it before "fixing" it with a PRRT I just did a check where I let the car idle in the garage(showing time vs. degrees): 0:00 32 degrees 7:30 90 degrees 12:00 91 degrees, bottom hose starts to get warm 15:12 94 degrees, fan starts (blowing the right way) 16:30 91 degrees, fan off 18:30 94 degrees, fan starts 20:30 91 degrees, fan off etc... At the end, the oil was at 75 degrees. Coolant temperature was read from the ECU through the OBD plug, dashboard gauge showed the same values as far as I could tell. Plan is to let the car cool at bit, then unplug all the sensors and commence boil testing Link to comment Share on other sites More sharing options...
gundersen Posted June 22, 2012 Author Share Posted June 22, 2012 Ok, so I tried putting the ECU sender in hot water and compare the ECU reading through the OBD plug with that of a thermometer in the water, and they showed exactly the same at 62 and 77 degrees, and one degree difference at 89/90 degrees. So I think it is safe to assume that the gauge/ECU is showing the correct temperature...which is unfortunate as a new gauge would have been much cheaper than the alternatives I also extracted the thermostat (mental note: far from all the coolant is drained by loosening the bottom hose, the rest is now on the garage floor) and put it into boiling water. It started to open around 90 degrees and it is stamped with 88, so I think we can assume that it is a 88 degree thermostat It was open 4-5mm at boiling point, but I am not sure how much it is suppose to open? I can see that some of the cores (is that the correct term?) of the radiator are bent, if that reduced the cooling capacity enough that could explain the high temps? Edited by - gundersen on 22 Jun 2012 21:33:09 Link to comment Share on other sites More sharing options...
CharlesElliott Posted June 23, 2012 Share Posted June 23, 2012 The ECU and gauge senders are two different things. The gauge sender is next to the ECU sender on the water rail but only has a single wire to it. The ECU uses temperature to determine fuelling etc. The fan is controlled by the fan switch on the radiator. Link to comment Share on other sites More sharing options...
CharlesElliott Posted June 23, 2012 Share Posted June 23, 2012 I would start by buying a new 82 degree stat and ideally replacing the fan switch with a slightly lower rated one. Link to comment Share on other sites More sharing options...
gundersen Posted June 23, 2012 Author Share Posted June 23, 2012 Quoting CharlesElliott: The ECU and gauge senders are two different things. The gauge sender is next to the ECU sender on the water rail but only has a single wire to it. The ECU uses temperature to determine fuelling etc. The fan is controlled by the fan switch on the radiator.I know But I think I have done enough testing to verify that all the bits are operational. 1) I have verified that the gauge and the ECU agrees on the temperature 2) I have verified that the ECU shows the correct temp, and thereby concluded that the gauge and gauge sender then also shows the correct temp 3) In the idle test the fan comes on and off at reasonable intervals, thereby verifying that both the fan and fan switch are working 4) I have boiled the thermostat and ensured that it open/closes at the specified degrees Quoting CharlesElliott: I would start by buying a new 82 degree stat and ideally replacing the fan switch with a slightly lower rated one.While I agree that this would lower the general running temperature to a more reasonable level, I cannot (with my limited understanding) see how this would help the trackday overheating? With running temps around 115 both the thermostat and fan have been fully activated long before that (fan at 94, thermostat fully at 100). Thanks again for all the input, I am continually impressed with both the helpfulness (is that a word?) and knowledge of the POBC. Link to comment Share on other sites More sharing options...
Johnty Lyons Posted June 23, 2012 Share Posted June 23, 2012 Your heat exchanger is being compromised on track either it can't get enough cold air through it to take away the heat going into it OR it's got plenty of air but not enough surface to take enough heat out. Either increase air flow or increase surface area(bigger rad). Link to comment Share on other sites More sharing options...
rj Posted June 23, 2012 Share Posted June 23, 2012 Bo, I don't remember... Do you have the mesh too or just the "7" grille? Link to comment Share on other sites More sharing options...
gundersen Posted June 23, 2012 Author Share Posted June 23, 2012 Quoting Johnty Lyons: Either increase air flow or increase surface area(bigger rad).Ok, so my next steps are: 1) try to build a duct that leads more air into the radiator as patneale suggested, and if that fails 2) Buy an radtech extreme with a 11" fan Quoting Rj: Do you have the mesh too or just the "7" grille?Just the 7 grill, so not much blockage in that I am afraid. I will be back with an update Link to comment Share on other sites More sharing options...
mav Posted June 23, 2012 Share Posted June 23, 2012 Quoting gundersen: Quoting Johnty Lyons: Either increase air flow or increase surface area(bigger rad).Ok, so my next steps are: 1) try to build a duct that leads more air into the radiator as patneale suggested, I do believe this was also suggested on page 1 of this thread 😬 Link to comment Share on other sites More sharing options...
gundersen Posted June 23, 2012 Author Share Posted June 23, 2012 Quoting mav: I do believe this was also suggested on page 1 of this thread 😬Indeed it was, sorry I missed that one Link to comment Share on other sites More sharing options...
CharlesElliott Posted June 23, 2012 Share Posted June 23, 2012 My suggestion of a new stat was partly to reduce temps and partly because I'm not convinced your current one is opening properly. Link to comment Share on other sites More sharing options...
mav Posted June 23, 2012 Share Posted June 23, 2012 Bo, I'm running my SV (1.6k supersport, wet sump with Apollo and laminova), with a radtec radiator (fitted in 2005 for theist trip). I experienced someodd temp behaviour across the USA and later in the uk too. Turned out the stat would erratically fail open or closed. I'd go with Charles suggestion and swap out the stat to start with, replacing it with an 82 degree item (rover diesel jobbie) and see how that works out. A careful refill of the cooling system would also be advisable to doubly insure against airlocks. Link to comment Share on other sites More sharing options...
mav Posted June 23, 2012 Share Posted June 23, 2012 Have a look here to find part numbers you may be able to use for cross reference. Failing that give me a shout and I'll pop into halfords and grab one to send you... Link to comment Share on other sites More sharing options...
gundersen Posted June 24, 2012 Author Share Posted June 24, 2012 Thanks Mav, mighty nice offer. I will see if I can source one locally, if not I may take you up on that Link to comment Share on other sites More sharing options...
gundersen Posted June 26, 2012 Author Share Posted June 26, 2012 Somehow I don't think I will have to take you up on your offer Mav Rj directed my attention to this, I think that will do Link to comment Share on other sites More sharing options...
mav Posted June 26, 2012 Share Posted June 26, 2012 That's 74 degrees though, so may be too cool. You ought to be able to find a suitable pattern part at your local parts supplier. Will be cheaper than shipping from uk, or at least should be! Link to comment Share on other sites More sharing options...
gundersen Posted June 26, 2012 Author Share Posted June 26, 2012 Hmmm, the GTS1102 is rated at 78 degrees some places and other places as 74 degrees...can't really make out what's the truth Regarding shipping, with the amount of parts we Danes buy from CC I think they are shipping it to us in 50 foot containers so shipping is not too bad. Link to comment Share on other sites More sharing options...
gundersen Posted August 18, 2012 Author Share Posted August 18, 2012 Well I am still waiting for the new thermostat from CC 😔, but I tried my home made radiator gills at a trackday last week. Unfortunately they did not help one bit, and temperatures where just as high as last time Seeing as my my bank account are in the black, for once, I might just go get myself a sledgehammer to crack this nut 😬 Sledgehammer being a radtec cooler with a mocal oil/water heat exchanger and a PRRT. Link to comment Share on other sites More sharing options...
charlie_pank Posted August 19, 2012 Share Posted August 19, 2012 I reckon you've got an air lock somewhere or your radiator is partly blocked. You could try disconnecting it at both ends and flushing it with a hose pipe. Also, you could try running the engine from cold with the expansion cap off to eliminate air locks... Link to comment Share on other sites More sharing options...
Roadsport06 Posted August 19, 2012 Share Posted August 19, 2012 The cooling system is up to the job for a 140bhp k series so a fancy rad is surely a bit OTT. Put in a new thermostat, put in a bleed tee, flush the rad (to check the flow isn't blocked), slowly fill it and see how you get on. If the thermostat isn't fully opening it could cause a problem, likewise a partly blocked rad or an air lock. Doing this will only cost a few quid and will eliminate the cheap things before moving on to replacing the rad with a fancy one. Link to comment Share on other sites More sharing options...
gundersen Posted August 20, 2012 Author Share Posted August 20, 2012 Quoting charlie_pank: I reckon you've got an air lock somewhere or your radiator is partly blocked.I don't know much about the persistence of air locks, but I have changed coolant three times (one time also changing all the hoses) while observing the problem. Of cause it might just be me doing it wrong, in which case I could change the coolant as many times as I want and still see the air lock Quoting Roadsport06: The cooling system is up to the job for a 140bhp k seriesAre you sure it is? I know of at least one other SV with exactly the same spec as mine which suffers from the same problem. Also a couple of answers in this thread suggests that the SVs might have a cooling problem. Quoting Roadsport06: so a fancy rad is surely a bit OTT.Well is a nice upgrade ever OTT? 😬 Quoting Roadsport06: Put in a new thermostatYou are of cause right, I could/should wait till I get the new thermostat from CC. Quoting Roadsport06: put in a bleed teeAlready done that Quoting Roadsport06: flush the rad (to check the flow isn't blocked)I will try that one, should be little extra work when I am fitting the new thermostat. As always, thank you for your feedback it is much appreciated! 😶🌫️ Link to comment Share on other sites More sharing options...
CageyH Posted August 20, 2012 Share Posted August 20, 2012 If you use the car in Winter, consider fitting the PRRT. It will help prevent the system over cooling, as there is no need to blank of the radiator. Apart from that, if you have verified that the temperature sender is working correctly, follow the advice above. Link to comment Share on other sites More sharing options...
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