Radiator woes again!

[Tony Leigh]

I know there have been many radiator posts over the years and I have read quite a few recently but thought I would start another just to get any current information/thoughts from everyone. My 2019 420R SV has developed a leak which I think is coming from the core near the bottom just above the oil cooler (my rad/cooler part no. is 30C064C-R300). It is one with the oil cooler attached to the bottom of the radiator. I spoke to Caterham cars parts dept. and the person I spoke to was very helpful and told me my design is no longer available and I need a slightly different one (part no. 300C0004A) with 2 additional brackets (part no. 300P0063A). The radiator is £682 and the brackets £3.10.

I know there has been quite a bit of discussion about vibration and cracked welds but I don't think my problem is a cracked weld. 
 

I am interested to know which way to go, either new CC parts, or a repair, or supply from someone else. I saw mention of a company called Alicool a few months ago but it appears they went into liquidation in May 22 and I have not contacted Radtec yet but their website shows no radiators available for Duratec engined sevens.

I will try and attach a couple of photos, apologies if they appear wrongly orientated as I know that occurs quite a bit, but I'm sure someone will sort them if I don't get them right.

More importantly I will be interested in views as to the best way forward

Tony

[Jonathan Kay]

I think...

Jonathan

[SM25T]

Remove it and take it to a radiator repair workshop ?

[ScottR400D]

A shame to hear of yet another radiator failure. I get the feeling that the 'upgraded' radiator system is worse than the system it replaced, poor as that was. 

Thinking about that how hard would it be to revert to the original system? As far as I know the water pipes fit that better than the current one and there are no concerns about strained pipes, dodgy brackets etc. Have the oil pipes changed?

At least the original rad wasn't massively overpriced, though it was still a bit silly at £366. 

Edited to add: Of course they're not in stock either....... 

[Beagler]

You didnt remove a bobbin to replace a broken exhaust bobbin? Just checkin'  

[ScottR400D]

Wouldn't have made any difference if he had.......

[Tony Leigh]

Jonathan,

Thanks for sorting photos- you did get them right.

Part of high cost is unit is supplied with a new oil cooler (which I don't need). I tried to just source radiator on its own but that doesn't seem possible even via a local specialist who buys lots of stuff from CC. Contacted original manufacturer (PMA, Leicester), but they only supply via Caterham or their dealers.

I contacted Radtec who were really helpful and offer a test and repair service with potential to supply a new (non Caterham) replacement if unrepairable. So, my plan is to send off to Radtec and see what they say.

Converting to old style does require a new (different) oil cooler and hoses (I think) so don't think it's worth exploring that option at the moment.

[ScottR400D]

You're right about the Oil Cooler Tony, you'd need the Mocal one (which does only cost about £70, as opposed to well over £200 for the one you have at the moment) and new pipes.

No doubt the best option for now is to get Radtec to have a look.

 

 

 

[ScottR400D]

You're right about the Oil Cooler Tony, you'd need the Mocal one (which does only cost about £70, as opposed to well over £200 for the one you have at the moment) and new pipes.

No doubt the best option for now is to get Radtec to have a look.

 

 

 

[7Up]

I went for the Radtec own version, fitted correctly (with shims to reduce any stress) by Premier Power and changed to blue coolant as advised by Radtec. All fine currently, guessing about 4000 miles later.

Alot of flushing is required before the coolant stays clear.

Iain

(2018 420R)

 

 

[Colin Heseltine]

I had a new radiator fitted in my 420R SV car in November last year, the car had done 5715 miles and car was about 8 months old, so still under warranty.  The new one started to weep a couple of months ago.  Just done a 2056 mile trip round Scotland which included a return journey of 480 miles in 11 hours.  Over the two weeks I added around 3 litres of coolant and I cannot pinpoint an exact location for the leak but there appear to be a number of them.  So this radiator has lasted just under 4500 miles.  I am talking to Oakmere about getting another fitted asap.

The car has 10700 miles from new in 18 months.  Am I going to need another in 5000 miles time or thereabouts, just as the car has gone out of warranty.  After the next one goes belly up do I bite the bullet and get a Radtec, or get Caterham to keep supplying new rads as the problem has not been sorted.  Radtec are only a couple of miles from me.  The last radiator I had of them lasted for 30,000 miles on my 1600 K series engine.

Colin

[Jonathan Kay]

Had you already checked the mounting and the load from the hoses for excess mechanical stresses?

Jonathan

[Colin Heseltine]

To be honest, no.  To my mind, Oakmere, The dealer, should be checking these things.  The car is a factory built one, still within warranty period.  The first radiator only leaked by the top hose connection.  This one appears to have leaks in several places.

Colin

[Jonathan Kay]

Thanks

Jonathan

[Geoff Brown]

Any one with a radiator leak going to Beaulieu ?  Then one needs to poke the new CEO in the chest on the subject.  And while you are at it also Titan/BMW Diffs !!

Historically the 'new' radiator/oil cooler assembly appears to be too rigidly mounted to the chassis which stresses it out. Leakage is the out come. I recall that CTR MINT in the IOM created a blog about re engineering the mountings to reduce stress ? 

The 'old' separate rad & MOCAL oil cooler works well. The rad is mounted with four rubber bushes so free from most stress & vibration with the MOCAL mounted in front at the bottom on independent brackets.

I do not recall any big problems with that set up. Pity CC changed the spec.

 

edited 26/9/22

[John Vine]

#15:

I recall that CTR MINT in the IOM created a blog about re engineering the mountings to reduce stress ? 

IIRC, CC supplied small brackets to lower the rad as it was hitting the underside of the nosecone.

 

The 'old' separate rad & MOCAL oil cooler works well.

I agree.  That's the set-up I have.  I did get a small ex-warranty leak early on (around 2009), but to their credit CC refunded my replacement cost.  I've had no problems since.

 

JV

 

[ChrisC]

Every post 2019 420 in the Essex group has had one or more replacement radiators.  That includes factory and kit built cars.  The real kick in the teeth is CC suppliers races with the rad and oil cooler separately and at a much lower price in comparison to the 420 road spec combined unit, even though the design is almost identical.

I am not sure why they are failing, is it the minimal vibration mounts, stress from the ill fitting hoses, vibration from the fan pressing against the 7 grill or the combination of all of these factors.  All I know is mine lasted 2 and a bit years, so failed outside warranty, and this is far longer than most have managed. 
 

The stack of new, unused 420 oil coolers (not available without the radiator) at the CC Easter parts sale tells you all you need to know about the current 420 radiator situation.  Obviously the CC techs find it easier to undo the two bolts holding the cooler to the rad, than drain and replace the oil cooler / rad combined unit.

I have never been happy with my 420 radiator design, and when it expired I realised for a minor increase in outlay I could convert to the 2008 - 2018 design, where the vibration mounts are bigger, the hoses fit, and nothing touches the grill or nose cone.  This was only possible because CC at the time still supplied the oil cooler mounting brackets and fan mounting brackets in my kit even though they where redundant parts due to the new design.

 

[ScottR400D]

IMO they're just badly made rads. 

As I've said before the first 3 I had from CC all leaked. I gave up at that point and had one repaired which has been fine since and still have one of the others as a spare though it still needs a repair before it can be used. 

They were all of the earlier separate oil cooler design so that was certainly no guarantee of a leak proof item!

"Any one with a radiator leak going to Beaulieu ?  Then one needs to poke the new CEO in the chest on the subject.  And while you are at it also Titan/BMW Diffs !!"

And if anyone needs a sharp stick I'll happily provide one........... 

[MTW]

I'm on my 4th rad, latest one was fitted under warranty by Caterham and lasted 3 months.

when spoke to Caterham about this, they stated the only way for me to get it replaced was for me to remove the faulty rad, BUY a new rad from them, send back the faulty rad for "testing" then after that they would refund me... I told them where to go on that one.

I am buying a rad from McMillan motorsport, they have them made to their own spec, with a different fan set up that's bigger and is on the rear of the rad rather than front, I'm going to give that a try, I have heard the McMillan rad is the one to have from a couple of Caterham race teams.

I also have a 620R silicone top coolant hose im going to join to the current rubber coolant hose to try and reduce the vibrations.

 

 

 

[PeterM]

Having recently fitted a third Radiator to a new 310 now at 8k miles (2nd Rad lasted 1550m) I have slackened back on the nuts either end of the rubber mounts to take as much tightness and stress out of them as possible without nuts coming really loose. There are spring washers there that should stop this. So far, so good after 750m. I will report back if it works in the longer term. 

[Jonathan Kay]

I haven't heard that tried before. The usual approach is to remove twisting stresses by enlarging the holes in or repositioning the mounting brackets.

There's some scepticism about whether spring washers in general prevent loosening. Nyloc nuts would be an alternative.

Jonathan

[John Vine]

#20:

My method is to:

1. Mount the rad loosely on the four bobbins
2. Check that the threaded section of each bobbin sits centrally in the slots of the rad mounting flange, with no tension or stress in the bobbin rubbers.  If necessary, enlarge the slots with a round file.
3. Pack out any gaps between the rad mounting flange and the bobbins with washers.
4. Secure with Nylocs.  (Agree about spring washers, JK!)

Has always worked for me.

JV

[ScottR400D]

I've never found nylocs work well on rubber mounts and they're not normally used because they tend to twist the rubber as you tighten them. That's why the mounts are sold with plain nuts and spring washers. 

It's true that split washers have been found to be not so effective but in this sort of application coming loose isn't usually an issue because the mount, of course, damps out vibration.

 

 

 

[7 wonders of the world]

Spring washer possess not self locking properties, nyloc / philidass nuts or Nordloc / schnorr washers or use a chemical locking agent

[ScottR400D]

"Having recently fitted a third Radiator to a new 310 now at 8k miles (2nd Rad lasted 1550m) I have slackened back on the nuts either end of the rubber mounts to take as much tightness and stress out of them as possible without nuts coming really loose. There are spring washers there that should stop this. So far, so good after 750m. I will report back if it works in the longer term."

I really can't see how slackening off the nuts would make much difference to any stress. As said, you need to make sure the mounts are lined up OK and not being leaned on by a bracket etc but for the actual fastening of the mounts tightening up the nuts is the right way to do it. They're done that way in just about every application they're used for.  

Doesn't the 310 have the 'old' radiator and a properly fitting top hose by the way? So not the same issue as the 420s appear to have and doesn't really have the problems associated with that mish mash of an 'upgrade'.