420R (S3) Radiator design issue, regular failures???

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CtrMint
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Thanks Chris, the fact you don't have any interference is certainly helpful and likely supportive of why I'm experiencing repeated failures.

There's no adjustment possible, due to the alignment of the 90 degree elbow and bolt holes.  I'm back to the frustration of my original build.  *smash*.  

Caterham 420R S3 Lotus Toxic Green,  Caterham 620R S3 Exocet Red. Blog: https://www.caterham7diaries.com
ChrisC
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Also the weld on your outlet doesn't look that convincing to me.  Sorry this picture is rotated, but your see the weld, and the fact the hose can be fully pushed home and have a hose clamp fitted.

Jonathan Kay
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CtrMint
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Chris, 

Do you have a pic of the bracket from the other side?  I'd like to send to CC, see what their view is.

Caterham 420R S3 Lotus Toxic Green,  Caterham 620R S3 Exocet Red. Blog: https://www.caterham7diaries.com
ChrisC
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Sorry I don't,  i Ironically at the moment I am also struggling with a problem and have the whole backend of the car disassembled, so have no space in the garage to remove the nose and bonnet.  I am killing rear wheel bearings and driveshafts every 1000 miles. 

John Vine
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IIRC, Mark's original build problem was that the top of the rad butted up against the nosecone.  The basic cause was that the "new" composite rad+cooler wasn't a good fit within the old nosecone -- they didn't match.  That hanger extension in #1 was CC's fix for lowering the rad and moving it further back.  The rad is still mounted on bobbins in the usual way.

Do current kits have the same "fix"?  I'd hope not as I'd like to think that CC have (a) rejigged the bracket or (b) reintroduced the earlier rad version (which, IME, did the job perfectly), or (c) redesigned the nosecone to increase clearance.

JV

CtrMint
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Yes John you are correct.  I was originally shipped the 'newer' radiator without the drop hangers, which ended up with zero chance of fitting the nose.

My original blog with an image is here.

https://www.caterham7diaries.com/post/what-a-load-of-bobbins

Though curiously I now think I still have an interference between the inlet and the hanger, which is increasing vibration and resulting in premature failure.

Caterham 420R S3 Lotus Toxic Green,  Caterham 620R S3 Exocet Red. Blog: https://www.caterham7diaries.com
Geoff Brown
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Looking at the bottom photo in #1 there appears to be an interference fit with the top fastener bracket(s)? This indicates to me that the bobbin is actually not doing anything as the complete mounting system is solid & not flexible.

There needs to be some shimming with a penny washer or two to provide clear space for the bobbins to do their job. But is there space to do this & accommodate the nose cone?

No wonder radiators are failing. 

ChrisC
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My chassis mounting bracket touches the top hose.  Only just, but it does touch. I can lift the rad to gain clearance, but it settles touching.  I am sure there would be a witness mark on the top hose.  Don't forget this top hose had a slimmer side wall to my original so that would have been even tighter (and less flexible)

CtrMint
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I been in a slackened everything, I can get maybe an additional 1mm of movement, you can just see light between the bracket and top port, but not much, and there is nowhere near enough to get the hose on.

I've also had a play with looking at ways to space out things to try and buy enough clearance, I just can't see a solution that works.  

If the holes in the radiator ali bracket are moved lower, it would lift the radiator up, and gain clearance but I suspect risk hitting the nose.

Spacing the bobbins or hanger forward doesn't work either.  

As far as I can see the only way to resolve it is to grind the hanger down and increase the gap  Nono

Caterham 420R S3 Lotus Toxic Green,  Caterham 620R S3 Exocet Red. Blog: https://www.caterham7diaries.com