tomifle Posted August 25, 2009 Share Posted August 25, 2009 A bit of advice please... K-series 1400cc, standard radiator etc. Had an issue a few of weeks ago where the coolant temperature went high and it spat some out of the expansion bottle. I found that the radiator had an air pocket at the top. As the car had had a good run before it overheated I thought that maybe some air in the system had just gathered in the rad and made a large enough pocket to stop the fan switch working and therefore the coolant got hot enough to leak out of the expansion cap. Anyway, I've since fitted a bleed-tee, changed the radiator bleed screw (had a very small crack), expansion cap and tightened all the the jubilee clips (replaced where they were a bit worn and wouldn't tighten properly). I've followed all I can find on BC about filling the cooling system including raising the front, massaging hoses etc. and I honestly think I get any air out. After checking the coolant level when cold and starting the car, all hoses get hot in the expected order, thermostat opens (82deg on gauge), fan comes (90deg on gauge). Take it for a run and the temperature sits at 80deg but if I stop the temperature rises enough to switch on the fan but as it does it leaks coolant out of the expansion bottle. Then the fan only starts to come on at 95deg+ if at all! (Due to an air lock forming I guess). Also if I switch of as soon as I stop, so coolant never gets hot enough to switch the fan on, let it cool and check the level in the rad, it's low and needs topping up! There's no other evidence of the HG being knackered. Coolant and oil are clean, nothing odd from the exhaust, although I see on BC that others have experienced a failure without the normal signs. I don't understand why air (wherever it's coming from!) would sit at the top of the rad. Wouldn't it work its way around to higher parts such as the heater hoses or expansion bottle? If the answers are as I suspect then the second part to my post is going to be... is there anyone in the Dorset area who knows a reliable, trustworthy, Caterham-friendly place to get the head lifted and checked? Thanks Link to comment Share on other sites More sharing options...
Badger Bill Posted August 25, 2009 Share Posted August 25, 2009 Head lifted! Steady on... Shirley the last resort is to lift the head, imagine if it is OK! Get ready for far more qualified people to advise properly, but I'd be getting a new top for your expansion bottle to stop that leaking and then keep trying getting the air out of the system, perhaps run it for a few mins without the top on the expansion bottle and do the hose wiggling etc. All is not lost yet by the sounds of things! Good luck BB ☹️BB ‹(•¿•)› ex-1.4 MavSport Link to comment Share on other sites More sharing options...
henry21p Posted August 25, 2009 Share Posted August 25, 2009 Check the back of the water rail where it meets the head. Leaks there can cause the system to not be able to pressurise properly. The bolts holing it in place are often replaced with ones that are marginally too long and therefore don't nipupquite right on the gasket. Also, eu2 water rails don't suit eu3 heads very well (the later water rail has a bigger flange on it which sits better and has more gasket area). Or at least that was the case on my 1996 eu2 k series engine. Advice re the filler cap is good. Also check the hoses for any splits that are only apparent under load, i had a hidden one that only let water out/air in when cornering as it opened up a teensy crack under load. Link to comment Share on other sites More sharing options...
shn7 Posted August 25, 2009 Share Posted August 25, 2009 Try replacing the header tank cap. They are known to fail and once they've allowed coolant out I believe should be replaced to have the best chance of avoiding a repeat. Steve. Sussex (West) AR Not forgetting Percy the Polar Bear who recommends Puddle Pet Care Link to comment Share on other sites More sharing options...
tomifle Posted August 25, 2009 Author Share Posted August 25, 2009 Thanks for the advice. I've already replaced the expansion bottle cap but I guess it's worth trying another one. I've also tried letting it warm up without the cap, no obvious air came through. I forgot to say that there's a steady dribble now from the jiggle valve and the little hose between it and the expansion bottle gets warm. How do I know if I've got EU2 or EU3 head / water rail. They don't look as if they've been changed so I'd imagine they're compatible (in fact the head's still got it's RAC seals on it). Lifting thehead will definitely be a last resort Badger BIll. I just can't see what else is causing air to get in the system. Is it worth having the rad tested? The "patina" suggests it could be the original one so could be a bit tired. I'll have a really good look at the hoses but any other ideas are welcome because it's driving me nuts! Link to comment Share on other sites More sharing options...
henry21p Posted August 25, 2009 Share Posted August 25, 2009 bet thing to do-don't worry about whether it is eu2 or eu3, just look at where it meets the head and see if there are deposits left from evaopation of coolant from a leak running down the back of the engine from the flange... or is it wet to the touch!? Also look for pipe problems/splits around the valve for the heater matrix. Link to comment Share on other sites More sharing options...
grahambiddulph Posted August 25, 2009 Share Posted August 25, 2009 This problem is exactly what happened to my K series 1600, after chasing the problem for about 6 months had to finally aknowledge that it was the head gasket. Gave the car to oily who confirmed that it was indeed the head gasket. car has been O.K for the last 12 months. Link to comment Share on other sites More sharing options...
TomB Posted August 25, 2009 Share Posted August 25, 2009 If it is an old 1400 (like mine was) it could be that plastic dowels have deformed & the head it moving slightly. I had a similar puzzling problem, whereby by engine would spit coolant out if sustained high revs where used. Cap change, bleeding, bleed T etc didnt solve it. I removed the head & the plastic dowels where bannna shaped, so the head hadn't been located properly. See my thread from 2004, with solution on page 3 ) ) here Link to comment Share on other sites More sharing options...
Pelico Posted August 25, 2009 Share Posted August 25, 2009 How old is the car....a hose might have perished. Link to comment Share on other sites More sharing options...
Stationary M25 Traveller Posted August 25, 2009 Share Posted August 25, 2009 I forgot to say that there's a steady dribble now from the jiggle valveYou don't want ANY leaks, as, if water can get out .... air can get in ! Link to comment Share on other sites More sharing options...
Nick Pargiter Posted August 26, 2009 Share Posted August 26, 2009 I had a similar problem with mine, air kept getting into the system and collecting in the radiator. I fitted a restrictor in the small hose to the top of the expansion tank and the problem stopped. It was an item that Caterham used to fit to the Vauxhall race cars, no longer available now though. All you need is a piece of round ali or plastic just a bit bigger than the internal diameter of the pipe (about 8mm I think should do), 10mm long and with a 1mm hole through it. It needs to be a tight fit in the pipe. It restricts the flow enough to stop aeration in the header tank that then gets drawn through the rest of the system and collects in the radiator. Worth a try before going to any more serious actions. Link to comment Share on other sites More sharing options...
tweeky Posted August 27, 2009 Share Posted August 27, 2009 I had this and i swapped all my hoses for silicon as i notised bad cracking on a couple and its done the trick. Tweeky In a purple haze Link to comment Share on other sites More sharing options...
Area Representative Tin Man Posted August 27, 2009 Area Representative Share Posted August 27, 2009 Over pressurizing of the system may be caused by a cylinder liner that has dropped below the recommended 4 thou, which is what happen to my K-Series. No obvious signs of head gasket failure, but because No 4 liner had dropped the action of the piston was forcing air into the cooling system, thus blowing coolant out at the top of the expansion tank. Regards John Link to comment Share on other sites More sharing options...
Mick Day Posted August 27, 2009 Share Posted August 27, 2009 Another source of leaking is the inlet manifold gasket. Useful info on Angus & Tessa's site: here Link to comment Share on other sites More sharing options...
grahambiddulph Posted August 27, 2009 Share Posted August 27, 2009 Spot on Tin Man, had the exact same problem on my 16k series. *smokin* Link to comment Share on other sites More sharing options...
tomifle Posted August 28, 2009 Author Share Posted August 28, 2009 Thanks for all your advice. I haven't had a chance to have a look at the car to check out your suggestions yet. I'll get to it tomorrow all being well and give the hoses, jiggle valve hose a good going over. The "dropped liner" makes sense with the symptoms I'm getting. If the problem persists and it's not obviously a cracked hose, leaking manifold etc. can anyone recommend someone in Dorset / Hampshire to take a look? I'm not sure I should risk driving it too far (to CC, Millwood or DVA etc.). I'm going to Dunsfold on Sunday (with or without the 7!) so I'll see you there if you're going Link to comment Share on other sites More sharing options...
ECR Posted August 28, 2009 Share Posted August 28, 2009 You can test for a failed head gasket with a hydrocarbon test kit. This fits to your header tank in place of the normal cap and if there are any exhaust gasses in your coolant (from gaskets or liners) then the fluid connected to the test kit changes colour. I have one but am a good way from you (in the midlands). Does anyone nearer have one you could borrow ? Otherwise I think Sealey do a fairly cheap kit .... Ex Chairman Roger 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