Smithy77

Exactly 803mm forward of the rear mount and the same distance up from the underside of chassis...

Please help folks! I've started drilling for this exhaust mount and as I've gone through the aluminium skin, I've hit something considerably harder - the chassis rail I presume! No sign of any captive thread. Not wanting to drill through the chassis I've stopped, but I'm worried that I could make a mess of it and don't know where to drill next. Can someone please advise what to do? Pic

I carried out the coolant mods to my K-series at the end of last year. The two inherant problems with the K-series coolant system are i) re-filling with the avoidance of air locks (caused by the relatively low mounting position of the expansion tank) and ii) keeping the coolant at a consistant and 'cool' operating temperature. (big flutuations in coolant temps are common in the standard set up due to the thermostat being fitted on the 'return side' of the engine) To overcome the first problem some people end up jacking the front of the car as high as possible to make the expansion tank the highest point. What others (and myself) have done is fit a bleed tee (like this) within the highest point of the bypass coolant pipe which goes around the back of the engine (near to the battery). You then use this as your filling point and if you fill it nice and slowly you shouldn't have any air locks. If you have a heater you should fit the bleed tee so that you can lift it up while filling so it is higher than all the heater components. To help with the second problem, you can fit an 82C thermostat (someone will be able to point you to the right part/number) in lieu of the standard 92C item. As I understand 80C is about the ideal operating temp. It is then also advised to drill a 2-3mm hole on the top most part of the thermostat which actually helps with both of the above mentioned problems. The thermostat is a common area for airlocks so the hole helps to irradicate that. Also, the presence of the hole means that the thermostat is never completely closed meaning cold water is always flowing into the hot engine coolant and helps to smooth out the gradient of temperature change, as oposed to having a big rush of cold water at once when the thermostat opens. Hope that helps

Just called the fabricators at lunch to discuss welding vs brazing and they had already completed the welding. I guess that put this debate to bed!!

Ian, thanks for the advise. Just to clarify, are you saying it would be best to get it brazed because the existing joint is brazed around the inside? All the other joints on the pipe look welded, where as the flange joint on the inside did look more like a soldered/brazed joint - I could be wrong!

So I've just dropped the water rail off at a local metal fabricators for repair. I'm aware that the general concensus on here for the same repair is to braze the joint around the outside of the flange. When I put this to the engineer, he suggested the he'd probably just weld the joint as it will give a stronger joint. I went with his advise and asked him to do what he thought was best, i.e. weld it. I don't know too much about the technical differences and merits of welding vs brazing to really decide what is best. What are the merits of brazing for this particular repair, and should I call them to change to brazing? Edit: I've done a little research on brazing vs welding, essentially: Welding - Uses much more heat, joins the two metals by melting and fusing them together, forms much stronger joint (I think this will mean it is also more brittle?), puts base metals under higher stresses and can alter physical properties (more so in thinner metals). Brazing - Use less heat (enough to meld the solder but not the base metals), joins the two metals by flowing solder into the joint via cappilary action, weaker joint (but does this give it more flexibility?), distortion/warping/stresses to the area is minimized. I would still like a second opinion from someone with more experience to advise which would be best for this particular repair. If I have interpreted things right regarding brazing being more flexible, perhaps this is the reason why this might be the favoured method? Cheers

AdC, thanks for the tips. I think I'm going to go ahead and book this soon - the price, location and format make it sound like an ideal first TD for me! Andy, is it definitely £119 per head? So if I wanted to take another driver in the same car it would be £238 for the both of us? from me for the 18th June!

Andy, Thanks for the pointers. I was referring to the free FCFS tuition which is sometimes on offer, just incase you thought otherwise - sorry my post wasn't very specific. Brands GP seems a bit daunting for a first track in my pride and joy.... not much run off round the GP section! I like the thought of Cadwell or Oulton but wanted to keep it reasonably local if possible as I will be driving the 7 there. Cheers Edit: Damn paragraph spacing!!

Andy, will there be any tuition on offer? Looking to book my first trackday in the 7 this year. Any recommendations of other tracks more suitable for a noob, bearing in mind I live on the south coast?

I'll go with the high heat stuff then - up to 600degC! Hopefully the finish will be just as good..... Thanks Charles

Hi Charles, thanks for the quick response. I briefly considered sourcing one second hand, but due to their notorious weaknesses I thought there would be a good chance of it failing again. I'm hoping with a decent repair it will be fixed forever. I'm ahead of you on fitting, as I've read that half the problems occur due to poor fitting. When I come to fit I'll clean/flatten the head/flange surfaces before dry fitting and tighten up the head/flange bolts. I'll then assess the front monting point and file down or pack out the mounting point as necessary to keep the flange joint nice and square to the head. I'll then re-fit it with a new gasket and a smear of RTV silicone. I was leaning towards Hammerite so I'll go with that. Is the Hammerite High Heat paint (matt black) overkill then, or will the standard Hammerite satin black do the job? The pipe must get quite hot where bolted to the head...

When replacing my coolant and upgrading to mikalor hose clips last Autumn, I must have put some excessive stress on the water rail / cylinder head flange joint as I now have coolant weeping ever so slightly. I'm pretty certain it is coming from the joint between the flange and water tube itself (as opposed to between the flange and head). I'm told / have read this is a notorious weak point so it looks as though the welded joint is failing. I plan on removing the water rail and taking it to a local fabricator for repair. I'm told a brazed repair is best. Can anyone confirm the what metal is used for the water rail and flange? Also, should I get it brazed around the outside of the joint (visible once fitted) or around the inside over the existing welded joint? I will likely have to re-paint the water rail after the repair and I assume some sort of high temp paint would be required. I've seen Halfords do 3 types: Here Here Here Which is likely to be best for the job? Or is there something better elsewhere? Cheers

I was parked up in the bimmer having my lunch at around 12:45 yesterday while you flew past. Got me all excited as spring is nearly here!

Mavic, fair point. However, tin top racing (Lemans, WTC, BTCC etc) are evolutions of road cars, therefore there is an emphasis to stay in-keeping with road cars (as opposed to a specific performance advantages, one could argue). I think most (if not all??) purpose built race cars, i.e. single seaters, use the more traditional small wheel/high profile set up, from F1 down to Formula Fords (OK, FFs might not be quite as extreme as the high profile of F1 tyres, but they a far from the rubber bands used in tin tops) But the point about having to design and enginer all other aspects of the chassis to get the most out of what ever tyre/wheel combination the car has is the pertinent point here - you could probably get small wheels/big tyres to handle just as well as big wheels/small tyres by designing/setting up the chassis accordingly. So I guess the optimum choice comes down to a combination of preference of 'feel' you want to get from the road, and what the basic Caterham chassis is best suited for - can anyone catergorically confirm the latter point?

Mavic, if that is the case, why have F1 cars used 13s with huge profile tyres for years?? Not for the comfort presumably...

I could be interested. I've just started thinking about the possibility of getting something like this but I haven't started doing any reading up on them yet. Sorry to be a bit wooly. Are you in a rush to get rid? Having quickly googled this particular bit of kit, it appears to be for use inside a helmet (aimed at motorcyclists). Does this mean it is not much use without a helmet? I was considering a comms system that will double as ear protection for touring etc.

Brise may be able to supply the solenoids seperately? I've just got a new Magneton complete from them...

I have decided to start planning my first tour in my first Seven later in the year (probably a week or so somewhere in France). Aside from full weather gear, carpets and leather seats, my car doesn't have anything else you would associate with touring. Does anyone have anything they no longer need/want, e.g. draft reducer, tunnel bag etc? Happy to consider anything on offer. Car is a 2004 S3. Thanks!

Hi Jonathon, If I'm not too late I'll take 2 tubes, 1 black and 1 red bag. I might also want the P clips you have mentioned, subject to some research in fitting. Thanks for organising!

I've wedged mine down behind my seat (along with tool kit and spare cables), although maybe not be so good for taller folk...

Found one! Les had one. That's two items I've need in the last fortnight and each time I've closed my wanted thread within 24hours - I love this forum/club! :-)

Andrew - That's very kind of you for the bolts, top man! Your starter is ready to go and will be in the post tomorrow No I don't think you did include the spacer, you're not missing one are you? I don't think I'll need one to be honest because I can just about get a ring spanner round it as it is, so may go without. Mankee - Thanks for the link, much appreciated - fingers crossed it bears fruit!

I have a Magneton starter on its way to replace the incompatible Brise high torque motor, but it doesn't come with the adaptor plate or fixing bolts. Does anyone have any spear they no longer need? Alternatively, if the parts are readilly available new at a reasonable price from somewhere (i.e. not from CC), then please let me know. Thanks

Thanks, ECR. I don't have a Dremel but I do have a round file so I'll try that first

Thanks, Charles!