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

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CtrMint
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I must admit I had mixed feelings over the new 170.  In one hand it's great they've been able to extend the market again etc etc etc.  On the other, I still have an 18 month old car with 900 miles and still haven't seen the required revision...  I've tried to avoid be grumpy over it.     

No eye or processes monitoring their "technical debt"......

Caterham 420R S3 Lotus Toxic Green,  Caterham 620R S3 Exocet Red. Blog: https://www.caterham7diaries.com
CtrMint
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Given the revised hose is still not the correct shape;
Next week I'm going to ring around and see what the cost is likely be to have to correct hose made.  If there's any fellow 420R owners that are interested, please let me know.  Economies of scale will certainly be a factor. 

Caterham 420R S3 Lotus Toxic Green,  Caterham 620R S3 Exocet Red. Blog: https://www.caterham7diaries.com
Jonathan Kay
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There are three trusted suppliers of silicone hoses, and at least one offers a Club discount.

Jonathan

CtrMint
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Thanks Jonathan, I'm familiar with those brands, though I do expect the supplier will be based on capability to provide a custom hose at an acceptable price point. 

Caterham 420R S3 Lotus Toxic Green,  Caterham 620R S3 Exocet Red. Blog: https://www.caterham7diaries.com
Colin Heseltine
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My April 2021 420R has a leaking radiator.  Initially found top hose too loose and horrible slime working its way down the radiator.  Checked it again today, cleaned slime and tightened up top hose a little more.  Then noticed a drop of water on floor.  Dried it and few minutes later another drop.  Close examination shows water seeping very slightly from several locations where the core is fixed into the end casing.  This is on engine side of the rad on right hand side as face the front of the car.  Have contacted dealer to get one in ready for 6000 mile service in 6 weeks time.

Colin

Also rather surprised to see oil level below bottom of dip stick.  Car has done 4000 miles since had its last oil change.

Jonathan Kay
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Could you add some photos of your layout and the position of the leaks, please, Colin?

Thanks

Jonathan

CtrMint
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Hi Colin.

Mine always failed between the top of the end casing and core, engine side, and nearside.  Your experience seems very similar, though I'm not sure what you mean by slime?

I'd be interest to know how thick the side wall is on the top hose.  As per the thread, I'm wondering if there's insufficient give in the hose.  If you've got the thinner walled version, it might also indicate the reduction in wall thickness isn't helping. Although you could have simply suffered from a quality issue.

Caterham 420R S3 Lotus Toxic Green,  Caterham 620R S3 Exocet Red. Blog: https://www.caterham7diaries.com
ScottR400D
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#106, Colin wet or dry sump? 

BTW I see that the R doesn't have a DS standard and it's not listed as an option? Is that right? Surely not? 

L7C
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Caterham 420R S3 Lotus Toxic Green,  Caterham 620R S3 Exocet Red. Blog: https://www.caterham7diaries.com
aerobod
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Also rather surprised to see oil level below bottom of dip stick.  Car has done 4000 miles since had its last oil change.

Hi Colin, I would say a new Duratec (not fully broken in) with the increased Caterham rev limit on the 420R that Ford never envisaged for the bottom end, can use quite a bit of oil when taken to the red line a lot.

When driven sedately on the road (keeping the revs below 4,000RPM around town and on long cruises) my R400D doesn't consume much oil, on the track when kept between 5,500 and 7,800RPM all the time it uses quite a bit, requiring topping up every track day. Caterham recommend checking the oil level frequently during track days.

James