callumskeat Posted May 23, 2015 Share Posted May 23, 2015 About a year ago I was having constant overheating issues with my 1.6 K-Series engine. This occurred when static only. Much welcome advice from Tech Talkers was gratefully received but with a new water pump, radiator, thermostat all fitted little had really changed.The Motorsport website (http://qedmotorsport.co.uk) describes the problem as follows and I quote directly: "This (cooling) situation is exaggerated further still when the system incorporates a remote radiator as in, for example, the Lotus Elise. The standard thermostat installation can give rise to a flow where the coolant is cycling through the pump and the engine but is not being directed towards the radiator. This happens as a result of the thermostat reacting to the temperature of the cooled water from the radiator (bottom hose) rather than the heated water from the engine. Removing the original thermostat, and fitting our thermostat holder in the top hose can eliminate these effects." I have fitted their Remote Thermostat Kit (88 degree thermostat with 16mm Tee)*. This has made the difference; the fan now kicks in and the engine sits at about 80-82 degrees and when static it behaves too; at last! Fitting is not too difficult, but you will likely need another litre of coolant due to the inevitable spillage. Drain the coolant using the bottom screw on the radiator with the upper one removed too as this aids the drain process; pass through muslin or similar before replacing into cooling system to remove any contaminants. (Have lots of paper towel to hand as it will be a little messy). Loosen off the thermostat jubilee clips and disconnect the 16mm hose that runs up to the heater. Remove the J-Tube. Remove the thermostat housing, but place a bowl or something similar to catch the retained coolant. This requires unbolting the retaining bolt that also holds the dip stick tube. Removing the thermostat can be an awkward grizz first time round as it sticks hard, but keep wiggling energetically and it will come out. (When replacing it use silicone lubricating spray as it will go into place much easier; and this applies to fitting all the hoses). Unbolt the thermostat housing and with a junior hacksaw remove the thermostat piston and pin by cutting the retaining arms. The plate or flange with the rubber seal must be replaced into the thermostat housing to keep the thing leak proof. Bolt back together, but do not gorilla the thing up as the bolt thread seats can come out. Replace the thermostat and bolt back into place along with the dip stick tube. Measure up where the housing should sit in the top hose, so it will not rub against the chassis. You may need to relocate the headlamp sub-loom connector if this gets in the way. Turn it through 90 degrees and plastie-tie to the chassis. Having identified carefully the correct cut site, slice about 60 mm from the middle-ish section of the top hose and fit remote thermostat into the top hose. Jubilee clip it all in place once it is reconnected. (Make sure the top hose does not rub on the locking piece for the nose cone screw fitting as this will lead to wear and leakage in time). Cut into the horizontal section of the 16mm hose that that comes from the base of the expansion tank into the submarine tube. This is best done by removing it. Insert the 16mm tee and replace and then join to the top hose external thermostat housing with the supplied small gauge hose. Ensure all jubilee clips are tight. Replacing the coolant is quite straightforward as there is no blockage in the system, without the usual thermostat in place. To refill with coolant, replace the bottom radiator bleed screw. Disconnect the heater top hose (the small ‘elbowed’ one that joins into the heater) and turn upwards. Keep open the top bleed screw on the radiator. Fill the expansion tank to the point where the radiator top bleed screw dribbles coolant and then put your finger over the hole and give the adjacent section of the top hose a squeeze or 2 to remove any air pockets. Do up the top screw. Squish the hoses all round periodically to remove air pockets; the expansion tank will likely glug. Then fill the expansion tank to the fill line and screw on the cap. Next top up the heater hose, squishing the radiator top hose (engine side) to expel any air. Place paper towel around the heater as spillages from squishing surges are inevitable. Fill the heater top hose until coolant dribbles out of the heater top metal pipe (showing that it is full and air free) and put your finger over the pipe. Top up the elbowed hose and then reconnect it. Mop up the spillage. This may leave a little too much coolant in the expansion tank so bring down to the fill line using a meat baster squirter thingy or similar to suck out the excess coolant and replace the cap. Check all jubilee clips are tight. Rinse off around the front of the engine compartment where spillage has occurred with a garden hose or similar (gently) to get rid of residual coolant as this strips paint etc. The fitting kit (£154.86 incl P&P and with very basic fitting instructions only) is at the following link:http://qedmotorsport.co.uk/qed-shop/view-all-products-in-shop?keyword1=+rover+k+series+misc+qed+remote+thermostat+housingI am happy to send photos if anyone wishes? Link to comment Share on other sites More sharing options...
SM25T Posted May 23, 2015 Share Posted May 23, 2015 Blimey .... £154 for a thermostat !! Mine sits at 80C all day long with an 82C thermostat and extra tee as per LF mod from Sept 2012. Link to comment Share on other sites More sharing options...
callumskeat Posted May 23, 2015 Author Share Posted May 23, 2015 Sadly no soul gave me the heads up when I asked the question and i did not find on blat chat. Regards Link to comment Share on other sites More sharing options...
revilla Posted May 23, 2015 Share Posted May 23, 2015 All mine needed was the thermostat drilling. I did it to make it easier to refill but by allowing a little flow with the thermostat closed it also prevents the radiator water from going cold then rushing into the engine when the stat opens. All the thermal cycling has gone and it just sits at 82C whatever I do. Cooling system otherwise completely standard. Link to comment Share on other sites More sharing options...
callumskeat Posted May 23, 2015 Author Share Posted May 23, 2015 Many thanks. I did drill the flange and still experienced the same issues. Rgds Link to comment Share on other sites More sharing options...
revilla Posted May 23, 2015 Share Posted May 23, 2015 I wonder why the performance of the standard cooling is so variable from one car to another? Some people find the standard cooling works absolutely fine day in day out whilst others suffer from persistent overheating and / or instability and cycling. Some cars are then fixed by drilling the stat, some people find the LF cooling system mod fixes their problems whilst others have reported it leading to airlocks and blowing coolant from the expansion tank. Some people swear by the full PRRT solution. Knowing how prone the K Series is to airlocks I wonder how many of the "fixes" are not really caused by the changes to the cooling circuit but by side effects of removing a previous persistent airlock trap? Not meaning to criticise or anything, I'm sure most of the problems are very real, just wondering out loud about why things seem to be variable from one car to another. Link to comment Share on other sites More sharing options...
Member Jonathan Kay Posted May 23, 2015 Member Share Posted May 23, 2015 Agreed, Andrew.Glad it's fixed, callumskeat. And I'm sorry you didn't get all the advice you wanted. IMHO this will be a lot better when we get technical wikis to accumulate the knowledge from the forums. Jonathan Link to comment Share on other sites More sharing options...
callumskeat Posted May 23, 2015 Author Share Posted May 23, 2015 I am inclined to agree. Only 2 years wise on this issue this andit has been hugely frustrating. I pushed the car through passport check at the French end of the Chunnel a couple of weeks back, much to everyone's amusement. No upset on my part at your copmments, they are very fair. But I think I am now there and it has been a frustrating journey. Off the France next weekend so a long run will confirm the fix I hope. Thus far no problems and fairly static temps. Link to comment Share on other sites More sharing options...
callumskeat Posted May 23, 2015 Author Share Posted May 23, 2015 Jonahan, I had offers to pop over and help and folk were very kind. Blat chat is a great forum and I am still very grateful for the help all have given. No complaints on my part; just an enduring sense of belonging to a great group of enthusiasts. Link to comment Share on other sites More sharing options...
callumskeat Posted May 23, 2015 Author Share Posted May 23, 2015 Jonathan, lousy spelling for which my apologies. Link to comment Share on other sites More sharing options...
revilla Posted May 23, 2015 Share Posted May 23, 2015 As Jonathan said, main thing is you've found a solution that works for your car and I'm glad to hear you're sorted. I'm sure your detailed instructions will be extremely helpful to others who find they need to go down the same route. Always good to get feedback written up for the archive after people have solved their problems - especially as there is precious little manufacturer backup for the K Series now and we're sort of on our own. BlatChat has got to be one of the best archives of problems and solutions around for these engines now and a very valuable resource indeed.Enjoy the trip to France! I'm jealous - my car will be spending the next couple of weeks in pieces in the garage while I sort out MY long term problem which I have also been chasing for over two years. A constant knocking at the back end which I at first thought was the A-frame bush gone but I was assured by a specialist garage that the bush was fine, so I've spent two years chasing every other source only to find - the A-frame bush has gone! Link to comment Share on other sites More sharing options...
Grubbster Posted May 23, 2015 Share Posted May 23, 2015 Some of you may remember that my 230 bhp K used to have the occasional problem on track days, sustained running at really high rpm would sometimes cause coolant to blow out of the expansion cap (even tthough temp indication seemed to be fine). Similar to Callumskeat I tried many things to fix it including a head gasket change (during an engine overhaul), fitted a PRRT, tried a new temp sensor but nothing seemed to work. Then a couple of years ago Tom New fitted a QED remote stat for me and <touching wood> it has been fine ever since. So it gets my vote!It's interesting that different solutions work for different cars - the K series must be a bit fickle, especially as the state of tune chages. Link to comment Share on other sites More sharing options...
callumskeat Posted May 24, 2015 Author Share Posted May 24, 2015 Good luck with the fix and thank you for the encouragement. Hopefully the weather will be kind aorund Laon. Should it interest you the event is annual. The contact is: http://www.sceniccartours.com/laon-historique-2016/4588023529It is great fun, but not many Sevens attend; at present anyway. RegardsCallum Link to comment Share on other sites More sharing options...
callumskeat Posted May 24, 2015 Author Share Posted May 24, 2015 Many thanks, I have crossed fingers most everything else that it works. Link to comment Share on other sites More sharing options...
Mark Durrant Posted May 25, 2015 Share Posted May 25, 2015 I fitted the QED remote stat to my R500K over 6 years ago and never had any issues with temperature even when stuck in a traffic jam at Le Mans in 35C heat. Another advantage over the standard stat is ease of access in the event a thermostat fails as it can be changed in 5 minutes. This might not be an issue for a road user however, in a car used for competition this could be the difference in making the start. Link to comment Share on other sites More sharing options...
Dorset7 Posted May 25, 2015 Share Posted May 25, 2015 I too have the QED remote thermostat kit fitted - rock steady temps and its a doddle to bleed the system through. £150 well spent in my opinion. Link to comment Share on other sites More sharing options...
callumskeat Posted May 25, 2015 Author Share Posted May 25, 2015 Amen! Link to comment Share on other sites More sharing options...
Edzup Ezzer Posted May 26, 2015 Share Posted May 26, 2015 I think variability in Caterham K series cooling installation behaviour is a good point. My 1997 1.6 Supersport has always been marginal when stationary. It doesn't take long for the fan to cut in if left to idle when standing still and takes ages (if ever) to cut out again unless the vehicle is moving normally. In normal useage this is not a problem and I've learnt to live with it. Fitting the bleed tee in the top hose at the same as fitting silicone hoses has not made any difference. A friend's 1.8K VVC behaves altogether better with a virtually identical layout, being quite happy to idle whilst stationary for several minutes. As I said, I've learnt to live with it but I may pursue the QED option if the ' 3mm hole in the thermostat' (the next step) fails to cure the problem. At least Mark, Christian and Grubbster's experience gives me some hope of finding a solution for my 1.6K. Link to comment Share on other sites More sharing options...
Englishmaninwales Posted May 26, 2015 Share Posted May 26, 2015 +4 for the QED remote thermostatMalcolm Link to comment Share on other sites More sharing options...
revilla Posted May 26, 2015 Share Posted May 26, 2015 @Edzup Ezzer - Interestingly mine is also a 1.8 VVC. I know the VVC head is a "better casting" as far as air flow is concerned - I wonder if the waterways in it are a bit better too, allowing a better circulation (flow rate) of coolant even when the pump is idling?I know Dave Andrews pays particular attention to fettling the waterways when preparing a head.Last year we got caught up the tailback of a massive accident on a motorway in the Netherlands. We were stuck there for maybe 2 hours. We didn't realise how bad it was so kept thinking we were about to move and left the engine idling. It was an absolutely blistering hot day. It was roasting sitting in the car so goodness knows what the underbonnet temperatures must have been like after 2 hours, but the engine never showed any signs of getting hotter than normal. The fan kicked in and out normally and the coolant temperature just cycled a few degrees either way as it did. Oil temperature just sat just above 80. I don't think I actually could persuade mine to get hot if I tried!I've also got a spare 1.8VVC engine rigged up on a trolley with fuel, electrical and cooling systems so I can run it. Due to the difficulties of mounting a radiator on the trolley I ended up using an MG TF radiator but plumbed in the wrong way around (i.e. the water flow is fighting against the thermosyphon effect, with hot water entering at the bottom) and a large metal plate blanks off half the radiator area, but that will still idle happily for hours on end on a hot summer's day without any sign of overheating.If I can manage to find the time, I may look throught the archives to see if there is any discernable pattern to which particular K Series engines struggle with heat - it might give some clues to which solutions may work best in different cases. Link to comment Share on other sites More sharing options...
callumskeat Posted May 27, 2015 Author Share Posted May 27, 2015 The experiences are very helpful to hear about. Is there a possibility that the temperature sensor heats up when static because it sits above the manifold down pipes? And this leads to raised and perhaps inaccurate temperatue readings? is there a possibility that exhaust wrap will lessen any such effect by containing the heat output? Just thoughts?RegardsCallum Link to comment Share on other sites More sharing options...
Edzup Ezzer Posted May 27, 2015 Share Posted May 27, 2015 Revilla - your suggestion that K series spec is connected to the cooling issues is a thought but I'm inclined towards the random affliction idea. Interesting though if you came up with anything. Meanwhile, anybody care to post some photos of their QED remote thermostat installation? Link to comment Share on other sites More sharing options...
callumskeat Posted May 27, 2015 Author Share Posted May 27, 2015 Very happy to do so. Struggling to see how? Can yer help please? Link to comment Share on other sites More sharing options...
Grubbster Posted May 27, 2015 Share Posted May 27, 2015 This is mine - Link to comment Share on other sites More sharing options...
Edzup Ezzer Posted May 27, 2015 Share Posted May 27, 2015 Grubbster, that looks neat and simple! Inevitable I guess that there are a load more hose clips but the layout is very straight forward. Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now