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

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CtrMint
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I do wonder whether the 420R race nose cone is actually the fix here. Correct me if I'm wrong but it has more space underneath, thus permitting spacing, and vibration damping on the mounts etc.  

Caterham 420R S3 Lotus Toxic Green,  Caterham 620R S3 Exocet Red. Blog: https://www.caterham7diaries.com
Blue7
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I am inclined to agree about grinding the hanger down but one thing I have noticed is that looking at the two photos, yours and #14, the chassis bracket in #14 is narrower than your chassis bracket and therefore has more clearance with / from the radiator outlet.  Here is a photo of the two brackets for comparison

CtrMint
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Interesting point, I'll ask Chris to measure the width of his.

My hanger has a width of 20mm,

Caterham 420R S3 Lotus Toxic Green,  Caterham 620R S3 Exocet Red. Blog: https://www.caterham7diaries.com
Blue7
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It looks wider than 20mm more like 25-30mm but photos can be deceiving.  Regardless, I think I would file down the area I have outlined in red to eliminate any contact with top hose or radiator outlet.   It seems ridiculous that you should have to do this but I had to shave a good bit off oil filler cap and Cosworth coil cover badge to eliminate contact with the bonnet, so very Caterhamesque 

CtrMint
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For a couple reasons I've opened dialogue with Caterham on this.

The main reason is what I feel is the unavoidable scenario which has occurred.  Only after repeated failures have I been able to learn and consider that something is amiss.  I'm not an experienced mechanic, mechanical engineer, and so predicting this failure mode was outside the scope of basically fitting the radiator with the supplied hardware.  My car also seems to have little adjustment and subsequent clearance, I suspect due to the holes in the radiator bracket, either way reaching a conclusion to cut down the hanger was never a consideration.

If the part was say £200 I'd probably chalk it up to experience, but over £600 plus shipping to the IOM, we're something completely different.

Caterham 420R S3 Lotus Toxic Green,  Caterham 620R S3 Exocet Red. Blog: https://www.caterham7diaries.com
ChrisC
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My hanger is 25mm wide 

John Vine
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I'm not a welder, but that welding in #1 doesn't look very pretty to me.  I'm wondering whether whoever did it had simply located that tube in the wrong place?

JV

Blue7
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Looking at the new radiator in the CC store, the location holes are elongated horizontally, can you slacken the mounting bolts in order to slide the radiator to the right so that the bracket will not be touching the hose?  Here is what I am suggesting:

CtrMint
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I've tried the adjustment, I can't get sufficient travel to clear the inlet.  I think its more height I need so cutting the bottom of the elongated mounting hole so it can be lifted is more likely to be successful.   However, if I do that, I'll need to torque up the bobbins really tight so they support the radiator, which will of course reduce their dampening effect.  I've made this argument to Caterham today, and I'm awaiting a response. The only other option is to add a spacer/insert onto the bolt so that it's raised on the ali edge.  I've bought a load of rubber hardware to trial and error this, but it's going to take time and the real disappointment is missing the Taffia run, two Caterhams off the road.  Ranting

I'm also waiting for clarification on the warranty claim.  

Oh interesting I'd been posting on Instagram ( https://www.instagram.com/caterham7diaries/ )all weekend about my prep work for the Taffia, the car looked stunning by the end.  Of course the last image was the failed radiator.  The amount of direct messages I've had as a result from people with similar issues is bloody alarming.  

Caterham 420R S3 Lotus Toxic Green,  Caterham 620R S3 Exocet Red. Blog: https://www.caterham7diaries.com
SLR No.77
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"However, if I do that, I'll need to torque up the bobbins really tight so they support the radiator, which will of course reduce their dampening effect"

There's something not right here Mark, are you suggesting the bobbin is just a rubber bush?  The bobbins should be a rubber cylinder with a threaded stud bonded onto each side, the studs do not contact each other. However much you tighten the studs it will not be detrimental to the damping provided by the rubber section.

Stu. 

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