Eccles

Three German Sevens travelling through Malcesine on Sunday and heading back up again today! *driving*

Nice job Good to see the design still alive and well!! Ivan

I know a while has passed but what with winter and breaking my leg I have now got it all sorted. Turns out it was getting air in through the bleed nipples, after replacing all the seals the problem was still there so I bought a pair of new calipers from Rimmerbros and fitted and the problem went away. The one thing I noticed with the new calipers was that the pistons retracted too far after releasing the pedal meaning there was an inch or two of nothing before the brakes came on. Reading on another forum it was mentioned that the seals can sometimes cause this and to push out the pistons a bit further (against some bits of wood/plastic so they don't pop out) and then push them back in and refit the pads. Tried this and now all fixed, brakes now bite at the top of the travel. Thought I'd update the thread so that it may provide an answer to anyone who has similar in the future. Cheers Ivan

If they are the standard brakes I think they will be Girling type 14 calipers and all the bits can be got from Rimmerbros. About £16 for a set of seals for both sides. There are also pictures of the calipers so you can verify what they are. Ivan

Hi john g, it does help me, I now know this can happen so I'm not going mad and doubting everything I do so thanks. That was the way I was trying to think of it ScottR400D, I know leaks through molecule size is a thing through talking to people at work but it's hard to relate that to a car brake system. The bores and pistons looked good when I did the seals but that doesn't mean I didn't miss something so yeah, as messy as it will be, taking things apart again is on the horizon. The flex lines are 14 years old, I have found someone on eBay selling seal kits for the Seven master cylinder that I have so have bought one as they don't seem that readily available. I'm almost tempted to bite the bullet and just do the M/C, get new flexibles, and new calipers (or new pistons, bleed nipples and checking where the nipple seats) rather than one thing at a time to minimise the amount of mess taking apart/brake fluid used. Cheers Ivan

It is a bit strange and I don't understand, yes I would have thought that there would be fluid coming out somewhere - must be but I just can't find it. I top up the system when I bleed the air out but no need at any other time. It was happening before I changed the seals, after reading about someone who had the same problem and air was getting passed the seals but then fluid wouldn't leak out. I was a bit skeptical but figured it was only £20 and a few hours in the garage so tried it. Think I'll try trying your idea 21jigsaw/JonT and clean all the joints and test for leaks with paper towel. I can put something on the TV in the garage and sit there with my foot on the pedal as I'm not sure I'll get the wife out there to help. Thanks all

Thanks for the reply, everything is original so about 14 years old. I was thinking it wouldn't be the master cylinder by how little fluid I would bleed before it was ok, the air comes out within the first couple of seconds of opening the nipple (using Easybleed) so was thinking it was already in the caliper.

I have got this recurring problem of air getting into my front calipers (standard Triumph brakes) after a couple of weeks whether I use the car or not. I only ever need to bleed 1ft of fluid out of each caliper each time for the pedal to become firm again but two weeks later the air is back again and the pedal goes soft. There are no (fluid) leaks in the system and have just replaced the piston seals and copper washers on the banjo bolt with no change. Anyone else had this/got any ideas where it is getting in from? TIA Ivan

I got the bolts from carbolts1 on ebay but switched to their black stainless ones after a couple of batches because of the rust. They are all M5 and think they are 12mm and 25mm off the top of my head. https://www.ebay.co.uk/itm/321390783405 Ivan

Hi Tim, You are correct in your guessing. Mine, a 2007 Sigma, uses that for the speedo and the gearbox hole is plugged up. Yours could be a mixture of bits as they changed over systems maybe? Ivan

I have 130lb on the back and 200lb on the front with Protech, car is only used on the road and I've been very happy with them. Unfortunately I can't remember what length springs or dampers I went for. If they know it is for a Caterham they will valve them accordingly. Ivan

That's quite a random combination!! Good to hear it's been sorted now though Ivan

As it's an ex race car the inertia switch may be within arms reach from the drivers seat as I've heard of them being moved so that if they get tripped on track they can be reset easily. Ivan

That's a shame, was sure one of those would be the culprit. How long will you have to wait for the car to be collected with the restrictions etc.? Ivan

Could it be the fuel pump? It sounds like the immobiliser is working as the pump primes and the engine turns over which it won't if the immobiliser hasn't de-activated itself. I don't know but guess there is a pressure switch in the pump that causes it to run when needed to boost the pressure back up again and it sounds like that isn't happening. Just a thought..... Ivan

I had this very problem a month or two ago. For me it was that the throttle return springs on the throttle boddies had relaxed a little over the years. I managed to bend a new stub on the main spring for a bit of extra tension and it is all good now. I have bought a spare set from Caterham but you will wince at the price for a couple of springs!! Ivan

Thanks both, will have a look at the pedal end and see if there could be a problem there. Hopefully the cable routing is OK as I have tried it a couple of ways since changing it.

Dear POBC, Please help! I have a problem with my throttle bodies causing the revs to sometimes hang during gear changes, the revs will hold high for a few seconds then return to idle. It doesn't always hang around the same RPM but seems to be related to how wide the throttle was open before and only happens when the engine is good and hot. The car is a Sigma 150 so has the Caterham throttle bodies on it. I have tried replacing the throttle cable, have balanced and rebalanced the bodies just in case there was something weird going on there, but have since seen that when I get it to do it while parked I can see the throttle doesn't return to its stop (also seen on Easymap), but this is only when the engine is running, I've never seen the throttle stay open with the engine off. I have also taken them off, given them a good clean, baked them in the oven for 1hr at 150c (shhh, don't tell the other half) to see if I can reproduce any tightness but it remains as free as anything. There are no tell-tale scuff marks down the bores if the butterflies were catching because of too much endfloat. Tried a new lambda sensor because I had one and it was a straw I hadn't grabbed yet. Both return springs are there and as strong as I ever remember them. Before I order a new set of bearings for the throttle spindles is there anything else I should be checking?? Any other ideas what could be going on?? TIA Ivan

Sounds similar to a problem I had on my Sigma, I had changed the flywheel to a lightweight one and on testing it it had what I can only call a very hard rev limit around 5-6K. Turned out the crank sensor was slightly too close to the flywheel and by spacing off .5mm fixed it. Must admit I didn't notice the tacho going mad - too busy wondering what the hell was going on probably. Probably not the same reason but may be worth checking the crank sensor and wiring as I think these pulses are what the ECU will use to work out the RPM. Just a thought. Ivan

I recently replaced mine with some black stainless C/S allen screws (on a black surround ) - looks much better!

I would imagine that would be the part for you too sylvaman. I certainly noticed the throttle bodies were a lot louder I'm in a bit of a quandary with the MOT, I would like to know if it passes with it on or not but the garage I go to have decided it's a visual test only car (which is great!) so if I rock up and ask them to try it they may test it properly next MOT. Not sure if it's the DVLA database that's changed or the guy isn't looking at the chassis number. Ivan

I had something that sounds similar (same Sigma engine), turned out to be the alternator belt tensioner. Looking at it I think the plastic pulley came loose on its bearing. Ivan

Hi Chris, I have a small batch arriving in the next week or so of which there are a couple of sets left unspoken for if you are interested. Cost is £45 (inc P+P) which includes the mounts and black stainless steel screws and nuts (doesn't include the brass pins which can be knocked out and re-used from the removed hinge part). PM me if you'd like set. Ivan

Protech will valve them to suit when they make them for you if they know it's for a Caterham. Been very pleased with mine Ivan

Do you have access to a Gunson's EasiBleed kit? I used one of the various lids it came with on the expansion bottle and cobbled it up with an odd bit of pipe and the pressurised the system (carefully) with a foot pump reading the pressure off its gauge. The release valve in the original cap is about 15.9psi so no need to take it beyond (or far beyond) that. My system was full of coolant as I just wanted to see where it was coming from before replacing the rad.