Smithy77

If you are on throttle bodies, it's a good idea to get the spring loaded version of the Rover TPS.

Any ideas in noise restrictions for Brands GP?

My poppers where held into the scuttle with self tapers. When I fit the aero I remove the poppers and refit them on top of the aero bracket with the same screws. The poppers then act like washers holding down the aero. When I switch back to the windscreen, I just refit the poppers. Simples

JV, will be interested to know how that goes

Would you fancy a swap with a silver aero cap?

JV, the short answer is yes! My dash was the original (I assume) from 15 years ago and was horribly dull and faded (with a brown haze/patina) with the carbon weaves blurring into one another. A good treatment of AG BJ really brought it back to life. I don't have a "before" pic unfortunately, but this was the result... Also works wonders on switches, light blocks and vinyl...

Have you tried rejuvenating before spending out on high cost re-coating/replacement? I've just used Auto Glym Bumper Gel on mine and they have come out looking like new.

There are some for sale on Facebook by Arnie

Well, Jonathan, I'm happy to report that temps (both oil and water, but more importantly water) behaved impeccably all day! Both seemed happy to sit at around the 80-85c mark all day long, both in the colder/wetter/pussy footing sessions and the harder dry sessions. (N.B. the temp guage under-reads by 5-10c at this sort of temp)All in all, very pleased that my own version of the OEM cooling system works very well, and as I've said, I now have the advantage of an accessible thermostat. I'm so happy with it in fact, I'll even put my cock on the block and go on record by saying that I'll do this mod on any future K-series I own! So fingers crossed, I shan't be bothering you with anymore K-cooling threads from me

Ian x2, thanks for the input. The female thread of the tensioner is not magnetic so assume it's aluminium, and the bolt conveniently has 10.9 stamped on the head - grade?

Andrew, thanks also for your digging, much appreciated. I would agree with your conclusion. So, the pulley is off and I can confirm the bolt thread is M8x1.25. It's a flattened cap head type bolt with a 22mm dia. head to clamp the inner part of the bearing. Suggestions on torque setting?

Noble effort Jonathan, thanks for the help. I'll remove the bolt and let you know the size.

Thanks Jonathan

I believe it is a Rover tensioner for the PAS pump

Thanks for that Darren. Unfortunately, that guide doesn't make sense to me at all when it come to fitting the alloy idler pulley: From reading that, it sounds like the bearing is left on the tensioner mechanism and the pulley is fitted over the bearing with it in place. No mention of torque setting for the center bolt holding the bearing to the tensioner mechanism. But the pulley has a flange on the rear face which the bearing is pressed up against. Surely, the bearing needs to be fitted to the pulley first, by pressing it in from the front on the pulley, fit the circlip from the front, and then bolt the pulley/bearing assembly to the tensioner mechanism?? If anyone could clarify (and confirm the torque setting for the centre pulley bolt) it would be much appreciated. New bearing arrives tomorrow and track day on Saturday. Thanks

Does anyone know the figure for the centre bolt holding the pulley to the tensioner mechanism? K-series CC/Titan gold pump set-up with Rover auto-tensioner and R500 flanged alloy pulley Thanks

7WOTW, yes it was strange how the PRT was behaving. I'm 100% sure it was fitted correctly - the single inlet end connected to the bottom rad hose, bypass hose from the top hose connected to the outlet with the springy pressure valve, and the outlet with arrow and the word "pump" connected to the return hose. Brand new genuine PRT too

http://www.ebay.co.uk/itm/162400625748

Jonathan, you will see from the pics a series of bits of blue masking tape in various places. These are where I take laser thermometer readings. Not the most scientific, but cheap and easy and it works. Generally, the water rail temp (adjacent to the sensors) gets to about 98c by the time the fan kicks in. The temp of the rad (adjacent to the thermoswitch) gets to 94c when the fan kicks in and it cuts out when it drops to about 85c. The temp of the submarine when the fan kicks in is about 90c, and the temp reading rapidly counts down like a stop watch with the fan on (to about 80c) while I hold the laser thermometer on it. All sounds pretty healthy to me.

Yes makes sense. That's why I made my bypass 16mm ID, as per the OEM set-up

Elie - Not that it matters now, but out of interest, what difference would that make? I did allude to the fact that your suggestion was as per the QED install/instructions, but I couldn't see how the different approaches would function any differently - they both bypass the radiator. I am assuming your comment relates to this diagram for the DIY "REMOTE" stat:

Well that works! Tonight I have been busy changing the cooling system as per my latest diagram above. Ran it up to temp in the garage and all behaved perfectly as expected. Then went out for a 30min test drive. No over cooling, virtually no thermal cycling. Works pretty OEM to be honest. Did some cruising at 40mph, cruising at 80mph, and then some higher revving at the end and the needle stayed between 78-82c the whole time. And when it did move it was very gradual, not the near instant 10c drop I had last time out with the PRRT. Acid test will be Snetterton on Saturday to see if my rad flow issue is sorted when I come in from some hot laps. Some pics: So to conclude, I'm back to OEM(ish) set-up with OEM behaviour, but now have the advantage of a very accessible thermostat. The differences between now and my original set-up, where I suffered badly with over-cooling, are: 1) stat moved up-stream, 2) new 82c stat with 2mm hole, 3) bypass which is not kinked. We can only assume really that the old stat, with a 4-5mm jiggle valve, was the culprit. The PRRT issues remains a mystery, but I would advise that they are avoided from my experience. Will report back after Snetterton. Thanks for the help

Cheers Darren. I don't think I'd get on with going statless, what with the worry of messing about with radiator blanking on cold days. I know it works for some people though. Ian B, the heater loop was "removed" for two reasons - 1) I don't have a heater and 2) with the Titan DS system, the close proximity of oil pipes crushes/kinks the bypass hose (reducing x-sectional area by about 50%) where it connects to the bypass inlet on the stat housing. I believe this is a standard Caterham "feature" on the DS K-series cars. I say "removed" because I technically I still have it, it's just moved from behind the engine to in front of the engine. This K cooling is doing my nut in, and the more research I do, the more my nut hurts! I just can't fathom the behaviour of my PRT. It's designed to equalise pressure, but I have poor rad flow at idle. It's supposed to prevent thermal cycling/shock, but not on my car. I am definitely ditching it. Regarding the remote stat idea, the more reading I have done the more I am sceptical about it. By all accounts it's does little to help and it removes a key feature that the OEM set-up was designed to do, and the majority of members I have spoken to seem to agree. Taken from a very well reference link in the BC archives: "The X remote thermostat Under this description fall some devices who shares the same principles, although different in shape and plumbing. They are originated from a completely inverted approach: If the original cooling system is no good, let use a cooling system which has proven to be very effective on other engines. This system follows the lines of the remote thermostat as fitted on CIB engines. Unfortunately the problems on the K are of different nature (as explained above). Fitting the thermostat on the engine outlet could solve the thermostat dynamic issue (because of the blending/dampening effect of the coolant inside the engine and the engine itself) and the static issue (as the coolant temperature at the engine outlet is higher compared to the inlet). The thermostat will work beautifully and also the temperature measured by the senders at the engine outlet should be stable. Sadly all the control over the flow temperature at the engine inlet is gone and any level of gradient and temperature fluctuation is allowed inside the engine, as long as the final temp is constant. Although this setup can't possibly prevent HGF in the long run, the risk of temporary overheating as described in c. is sensibly reduced." So where does this leave me then? Well, going back to the beginning when I had the OEM circuit but I was suffering with the bad over-cooling, I think the problem was associated with the fact that the stat which I removed (when converting to the PRT) had a very large jiggle valve in a 4-5mm hole. I'm hoping the stat was the problem causing the over-cooling. I think I'm going to try and go back to an OEM set-up but with a minor variation (don't worry, there is method to my madness ), and that is to move the stat a little way upstream of the coolant inlet, but still on the cold side of the radiator, like so: "Why would you not just go totally OEM?", I hear you cry. Well, unless I am missing something, the above set-up should function in exactly the same way as the OEM set-up. The plumbing, in theory, is exactly the same, except for the fact the bypass and stat are now in front of the engine instead of behind. There are also some advantages to this over standard OEM: 1) The bypass is not kinked. 2) Access to the stat is improved by about a million% 3) There is a longer path for hot/cold coolant to "blend" before hitting the pump (possibly irrelevant?). 4) I have all the pipes/hardware to do this with a neat instal, so it will cost nothing and I can leave the inaccessible original stat housing well alone. I'll be using an 82c stat with 2mm hole drilled. The new stat housing will have to be fitted in the VERTICAL section of the S-shaped bottom hose - will this have any adverse effects on operation? Am I mad, or is this ingenious?

Time for an update. So just as a quick re-cap, with the OEM cooling set-up I was suffering with chronic over-cooling: I then tried running with the Rover PRRT set-up as follows: Over-cooling successfully eradicated. However, while on a track day, the above set-up gave me the problem/symptoms of poor rad flow at idle. When I came off the track, the rad seemed to really struggle to get rid of the heat from the stinking hot engine and the rad fan stayed on constantly for 15+ mins while idling in the paddock. As was discussed earlier in the thread, I then tried reducing the 32mm bypass to 16mm in an attempt to increase rad flow. This did seem to have the effect of increasing rad flow at idle as the average time the rad fan stayed on during a heat cycle seemed to drop by 10 seconds or so (very similar ambient temps). Now, I've not tested this thinner by-pass on track yet (Snetterton booked 25/02), but I took the car out for a road test on the weekend and experience yet another issue - an increase/exacerbated thermal cycling. Having let the engine come up to temp (20mins driving), I'd be cruising along at 40-50mph with the temp nice and stable at an indicated 80C. As soon as I boot it and give it higher revs, the temp suddenly goes from 80C to 70C - not good for the head gasket! So, I'm now thinking of ditching the PRRT and going for a remote stat in the top hose. Not an expensive QED stat, but using a 2nd OEM stat housing in the top hose with a drilled 82C stat I have spare: The are 2 main difference I can see between my version and the QED set-up: 1) My bypass from remote stat T's into the 32mm bottom hose, where as the QED kit has you T it into the 16mm hose between expansion bottle and submarine pipe. (This is mainly because I already have the hose cuts and hardware for this, but I also think it could have the advantage of a) reducing the volume of the rad circuit, and b) increasing the distance for hot and cold coolant to "blend" before entering the engine. 2) My OEM bypass is deleted completely, but I think the QED kit might assume there is a secondary bypass for the heater. Before I go ahead and cut up my cooling system, AGAIN, I just wanted a sanity check to make sure I'm not doing anything stupid. Any other views/observations also welcome. Thanks!

Long shot, but as the title