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

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Colin Heseltine
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Pic 1 shows slime from leaking top hose

Pic 2 Closeup of top hose and cores

Pic 3 Bottom side of core

Pic 4 Bottom side of core (slightly clearer)

Pic 5 Cores by top hose

Bright (highlight) spots are water seepage

 

Regarding oil.  The car is dry sumped with the triangular tank.  The dip stick is the correct one as per Post #110.  I have emptied the catch tank a couple of times.  Maybe total of 3" over three empties.

Colin

Jonathan Kay
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Thanks

Jonathan

ScottR400D
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I guess you don't know how much oil was put in, in the first place? 

The reason I ask is because in 6 years I've never had more than a few drops of emulsion in the catch tank, I'm surprised you've had maybe 3" of stuff from there and wondered if it had been overfilled. 

Regarding the oil level I'd again be surprised if the dipstick was a measure. Over the years I found that the level can vary a lot depending on how long the cars been stood and I've found that the only consistent method of measuring is to stop the car after a decent run, remove the hood and nose and see where the level is in the tank, aiming for 20-30mm below the second baffle, which equates to 7 litres of oil. 

I've found that sometimes the level will drop quite a bit once the car is left to stand and cool and other times it doesn't drop at all. No idea why. 

As for the radiator, that leak could be down to inherent faults in the radiator or could have been induced by stress from the hose, I guess, which does raise the question of whether CC's 'solution' makes any difference at all, assuming that you have the new hose. 

That's  an SV too isn't it, so the slightly different layout isn't making any difference, if it is a stress issue. 

L7C
Colin Heseltine
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Because it will be getting an oil change in 700-800 miles time (booked for early Nov) I have topped it up so hot it is just on the lower edge of the hot mark on the dipstick.  Level was tested by warming car up, switching off, waiting 30 seconds, then dipping the tank.  I assume that the level is with the dipstick fully screwed down.   Hopefully out on a run tomorrow so will check to see what has been lost (if any after the run).  Luckily do not need to remove the nosecone completely, just remove the two top Dzuz clips and it tilts forward nicely.

Can anyone confirm who makes the radiators for Caterham.  Several people have mentioned they through it was RADTEC.  If this is the case they are only a couple of miles from me so could pay them a visit.

When check it tomorrow I will measure the diameter of the top hose and check the thickness.

Colin

ScottR400D
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I'm not sure that whoever makes the radiators would own up to it..... Wink

L7C
Colin Heseltine
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Smile

CtrMint
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Based on the labeling on my replacement radiator,  it was made by PMA Group in Leicester.   It's on the part label, top of the radiator if the same.

 

Caterham 420R S3 Lotus Toxic Green,  Caterham 620R S3 Exocet Red. Blog: https://www.caterham7diaries.com
StevehS3
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Colin Heseltine
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Just checked my top hose.

OD 45mm

Wall thickness 6mm

Radiator is a PMA

Drysump tank is tapped and has 3/16" allen key plug in it.

Colin

CtrMint
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Thanks Colin. 

I've finally had chance to compose my blog post for those that might be interested.

https://www.caterham7diaries.com/post/modifying-the-radiator-mount

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