Tomiam

Is it ok if someone else is doing it though?

If its not too much trouble i would love a copy of those articles too.

Finally got time to get this sorted. Undid a bunch of pipes to release the old coolant and then stuck a hose pipe on them to flush them through. Much to my surprise there was no 'mud' in the pipes or radiator. Only at the top of the expansion tank as a very thin film. Got it all running clear and then let it drain for half an hour whilst I went to Halfords and got some G30 coolant. Installed the bleed piece I mentioned earlier up by the heater as well. Filled her up, bled out the air through the top of the radiator & t piece. All went well. Left her idling for 15 mins or so with the cap off to assist with air removal. Took her out for a test drive for 20 mins and temp never went above 80 on the gauge. Left her in the garage overnight and there are no pools of coolant on the floor this morning. :) There is still a hesitation in the engine at just under 2,500 rpm but that's got to be something else and not connected to this. Im just relieved its not a head gasket failure as Im sprinting this coming weekend! Fingers crossed this is now solved! Thank you all very much for the advice and steerage. Next step, to teach myself about about throttle body balancing and throttle position sensor settings. :)

Yea thats what i have in the handbook which came with the car. 'Red' isnt that helpful.. :) Thanks for the recomendations :)

Put new expansion tank cap on. Did some other bits n pieces like pedal position adjustment and replace throttle cable (original one was too short to allow me to move pedals). Went out for a drive to see if any issues with coolant. Within a few miles the cabin was ridiculously hot!! Cheched the heater and it wasnt on. 20 mins into the drive and im getting fried... Then remembered id not put the top of the pedal box back on.. oops! On a more positive note.. no coolant leaking. Ive also ordered one of these http://www.carbuildersolutions.com/uk/black-nylon-16mm-joiner-with-bleed which i will put up by the heater. Once thats in.. then i'll do a full flush and check thermostat. Just dont like the idea of having coolant system drained for ages. Any recommendations for red coolant?

Hi folks. Cap hasnt arrived from fleabay yet so ive not got any further forwards with flushing. Will be doing that this weekend. With regards to the compression test. I also did a chemical test on the coolant which was negative. Given the reasonably close figures on yhe compression as well.. im leaning towards no HG failure. Will update later this weekend for sure. :)

Thank you all. New expansion cap ordered from ebay. I'll take out the stat this evening and test it. You're right, checking the stat is definately worth doing and Ive got a few days to wait for the cap to arrive as well. Coolant flush.. here we come. Point noted about positioning of expansion tank and height. I will unattach the expansion tank, still connected to system, and raise it higher up as well as getting the front wheels up on ramps when refilling.

Cheers folks! I hadnt thought about the opposite of pressure increasing. Ie. The cap failing. Worth a shot. Likewise stat failing. Although im not getting any erratic / high temperature readings. Will start with coolant flush and new cap. Then go to stat aftwr. Advice very much appreciated. :)

Fair comment and thank you. I did a gearbox oil change last week and going by the state of the magnetic plug.. id say that had never been done. Chances of coolant being done are likely slim as well given what i know about the cars history. Just did a chemical test and nothing showed up. I'll try flushing the coolant and see if that helps with the mud aspect. Just cant get my head around the expansion tank being full (no air) and coolant being forced out aggressively and then it being perfectly fine. Sorry if this comes out as 1 paragraph.. posting on my phone and this forum always looses the formatting..

Cheers for the steerage Jonathan. :) Found a friendly garage willing to loan me a chemical tester so I can check for leaks. £10 & a "Thank you!" is better than £50-£60 for a one off test. Pretty sure this article I found describes my situation: http://singletrackworld.com/forum/topic/car-trouble-long-term-head-gasket-problem Minor leak. Occassional loss of fluid. Caused by exhaust gas pressurising the coolant system. Guess I will see when I test it later :)

I must be the odd one out. I get the engine warm, then remove the drain plug from the bottom of the sump tank and the drain plug from the bottom of the sump itself. Having now heard about the sump drain plug being a possible risk area.. I must admit to being tempted to spend the money on a pump though. :)

Just had another look at the expansion tank. Took the cap off and there is a slight brown film on the inside. Its also around the inside neck of the tank and all over the top of the tank (on the inside). Feels like very fine mud, if that makes sense. In short.. some form of contaminant is definately getting in. Anyone think of anything else to add to this?

Righto.. seems like a chemical test is the least expensive way forward. Although not exactly free either. Do you happen to know if the coolant remains contaminated forever after its been in contact with exhaust gases? I would still be interested in knowing if those compression readings are normal, assuming someone knows ofc :)

Compression tests updated in the above post. Sorry about that.. tried to make it easy for people to help me, but was following an internet guide which didnt mention having to have the accelerator pressed when doing compression tests. Engine temperature remains completely normal. ie: in the middle of the gauge. I've just had a 6hr drive back from Anglesey to Bristol and I was keeping a very close eye on the temp. Nothing wrong. Likewise, nothing wrong on any of the sprints or the driving up to Wales (6hr trip). Coolant - Im assuming one of caterhams own. I've owned the car for a year and a bit now and its always been 'red' in colour. I've only ever added water to it. Didnt know about chemical testing. I will google it now.

Hi All, Im in need of some steerage towards the right direction please. I have a duratec powered 2008 R400 with Roller barrel throttle bodies & I believe I have a head gasket issue. Symptoms. Drove it for 25 mins, starting from cold. Got to Anglesey circuit and parked up. Coolant is pouring out from the expansion tank. The expansion tank is completely full of coolant. ie: there is no gap in there for 'air' at all. I believe this may be caused by a leak in the head gasket which allows exhaust gas to enter the cooling system, pressurising it. I did nothing bar squeeze some water pipes and then did 8 runs at a sprint there without issue. Drove it back to the premier inn, not one drop of coolant dropped out. Its done this once or twice before in my garage after being out for a short drive but nothing as major as the amount of coolant coming out this time. Engine sounds like its 'missing' every now and again at higher rpm. Nothing massive but its not running 100% smoothly. On a score of 1 - 100, Id say 93. ie: I came 6th overall in my sprint vs other decent competitors so its not like the engine is a bag of spanners, but its just slightly noticeable. Starting always requires a very small amount of throttle. Not sure if this is related or not, but its not of major concern to me. Friend driving behind reported a few bits of white smoke coming from the exhaust every now and again about 1 hr onwards into our 5 hr trip. Figured all of the above is pretty much fluff and the best thing to do would be a compression test: Im new to this so this is how I did it. Took out all the spark plugs. All 4 were taken out before any compression test. Put meter onto a cyclinder and cycled the engine (by ignition) for 6 turns with the inertia switch disconnected and accelerator fully depressed. Engine was still warm at this point. I started on cyclinder 1 and then did cyclinder 2 , 3 & 4 in turn. Readings I got were. 1 = 225 2 = 243 3 = 215 4 = 220 Are these readings normal? Any thoughts, advise or plain old.. 'you should do this to test' direction would be appreciated. :)

Did the same for mine last week. Agreed, much smoother gear movement now. :)

This is probably wayyyy off base as my mechanical knowledge is slimand im trying to remember an issue we used to have a van. I think it had a blocked breather pipe. It would exhibit those same symptoms ive read above. Nightmare to get started once itd been left for ages as the vacuum left in the tank slowly pulled fuel back but once up n running you could restart without issue. Anyways.. this may / may not be of use but i thought id throw it out there in case it helped.

Hi John, I didn't initially bleed the cable, but I realised it would have air trapped which is unlikely to ever get out. So yes, I bled it. I ended up getting the oil line in place, poking out the dash and then starting the engine. A little jug underneath was plenty to catch the small stream of oil coming out. I must admit I was expecting it to be fired out the cable like a super soaker... glad it wasn't :) Can't say I noticed any difference in response time. In terms of the route, I had a look at the bunch of cables in front of the gear stick and there was nowhere near enough room for me to put anything through there. So I opted for drilling through inside of the heater blower cover and then feeding it out the bottom of that cover. I did have to drill an additional hole in the bottom of the heater blower cover to allow for drainage. Photo shows the cable just going through the bare hole, but Ive got some rubber grommets coming from car builder solutions to tidy that up. ps: Its a bit of a pain to post photos on this forum.... ;) ,

Right then... figures as promised. Test drive completed. Cold idle 68 ---- Hot idle 35 ---- 4k rpm 70 Pretty much the exact same as yours John. That's with Comma 5w/50

Hi John, Not a problem to share pressure readings. We've both got R400's so makes sense. Assuming all the bits n pieces arrive (Im doing an oil change and a bit of maintenance at the same time) then I should be able to post them this weekend.

Just wanted to say "Thank you" for taking the time to post this info. My OP sensor died on a track day a week ago and if I hadnt found this post it wouldve taken me a heck of a lot longer to put everything together. You've helped me out in the past with your posts Mr Vine and this is no exception. :) Very much appreciated!

Double post.

Hopefully it's not, but when my lambda failed that was one.of the symptoms. Lots of black soot coming out the exhaust. If you have / can borrow a cable to plug into the ecu (available from sbd motorsport) that would tell you very clearly if it had failed via the free software (easimap).

Not a problem. Hope it helps someone ;)

Hi Jonathan, Ive got a few of the images reposted below. Before: I dont have any "After" photos sorry, although its not hard to imagine a clear coat on the CF. :) Ive got to say that Ive not had any issues with white spots appearing on the carbon fibre after I gave them a number or coats of clear. It was nearly a year ago when I did that too. :) Ive got a large selection of meguirs and autoglym products which I use to look after her but generally speaking I only wash the cycle wings and then leave them to dry.