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

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CtrMint
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Hi JV, 

The radiator (should - not hung it yet) be in exactly the same location.  I've drilled a hole lower down in the bracket and chassis, and then cut the old hole / top off.  The 12mm or so of the old bracket is what's I've gained in terms of clearance with the inlet port. 

Caterham 420R S3 Lotus Toxic Green,  Caterham 620R S3 Exocet Red. Blog: https://www.caterham7diaries.com
CtrMint
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This the end result, all being loose.  So the hole into which the radiator bobbin goes (below) is in exactly the same location.

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

Jonathan

John Vine
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Good solution!

JV

CtrMint
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Final result., loads of clearance now.  Car is currently cooling in the garage, ran out of time before tea, assuming its all good but will check for leaks later.

I also used a small OD rubber washer and nylon washer between the bobbin and hanger just to try and suppress (reduce) any vibration.

It was a bit of a pig to get central on the bobbins, but eventually got there.

Caterham 420R S3 Lotus Toxic Green,  Caterham 620R S3 Exocet Red. Blog: https://www.caterham7diaries.com
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Nice one Mark, the washer you mentioned, this has should have increased clearence between the rad and button head too..?

If you have some to hand, use a thin plain washer (form B)  under the nyloc securing the two brackets, spring washers are best put in a box and weighed in for scrap. the nyloc needs no assistance - not that they offer any !

CtrMint
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Cheers Neil.

I didn't want to over tighten the hanger to chassis nut as I wanted the rubber washer id inserted between to at least have some chance of helping reduce vibration, so thought a spring washer plus the nyloc was a safe bet.

 

 

Caterham 420R S3 Lotus Toxic Green,  Caterham 620R S3 Exocet Red. Blog: https://www.caterham7diaries.com
ScottR400D
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So did CC send you another rad? Sorry if I missed that post! 

Geoff Brown
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Good fix. You need to add step by step instructions with pics to Guides - Maintenance. This addition will assist others who will come across the problem.

Also submit to CC for a workshop notice ? No that is a silly idea as they could not have an owner bettering them when it comes to practical design & innovation ?!

CtrMint
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Might be a good idea, but I'm slightly suspicious I haven't solved the fatigue issue completely.

I noticed this evening there is still a significant amount of vibration being absorb by the rad, not from the chassis mounts, but the large diameter stiff hose at the top.  Holding that you can feel most of the vibration at tick over in that hose, rather than the chassis.  I'm wondering whether I should try and swap to a silicon hose, maybe cut the stiff hose and use an insert to extend into a silicon hose, which might suppress more of the vibrations.

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