620 Cooling - Radiator Bypass Loop

[Doctor]

Don't worry Mark, I think our solution is reproducible. Taking it on the track on Monday, Mark now (thanks to you I believe) knows how to get the numbers out, we can compare his and mine. 

[CtrMint]

Having last-minute doubts about cutting up a warrantied car!  So phoned the Motor Ombudsman, after a lengthy discussion, turns out Oakmere aren't signed up on the sales side, only service and repair. 

[Doctor]

What does them not being signed up on the sales side mean??

[CtrMint]

The Ombudsman would normally handle/mediate a complaint or dispute between a consumer and retailer.  A dispute over,,, say a car with a questionable cooling system and no sensible solution, leaving a consumer with a car stuck in the garage unused.   

I'm suffering last-minute concerns over my warranty etc, cutting into my car and fixing a problem that shouldn't exist etc.  It's just a wobble   As a result I wanted to exhaust all options first.

If anything being aware of this information adds weight to fixing the problem myself, either with the PRT or other solution.   I also called South Coat Performance today, our local Caterham expert.  He's confident in supporting me with the Sadev, he's loads of experience, ex Bell and Colvill, worked for Lotus and F1 supply chain, so knows his stuff, and a sound bloke too.  

 I've also surfaced some information regarding a better non factory map for the 620 developed by MBE, trying to find out more at present.  

[Mark w]

Mark

its not a new map by MBE , they just sell the ECU hardware . If you want a map specific to your car rather than a generic one then you need to take it to a specialist and put it on a rolling road . 
if you then want a map that takes fuel pressure into account you need to add a fuel pressure sensor to the car and upgrade the ECU to one that reads fuel pressure ( circa £3000 from memory ) if you do that Jim H has proven 355bhp .
 

Once you've changed the ECU you can add flappy paddles to the gearbox .......for £xxxx

 

 

it never ends ......

 

edit to add mapping issues are not specific to the 620 , you can read about many other models benefiting from a specific map . I had my previous R400 remapped , the generic map on that wasn't great , my 620 on the other hand runs much more smoothly with the Caterham map . .

 

[aerobod - near CYYC]

if you then want a map that takes fuel pressure into account you need to add a fuel pressure sensor to the car and upgrade the ECU to one that reads fuel pressure

The standard MBE 9A4 ECU can take a fuel pressure input and compensate the fuel maps based on that input. This isn't used by Caterham at all, but an unlocked ECU allows one of the programmable pins to be designated to fuel pressure. It is fairly easy to add a pin to the Delphi connector (I've done this on my R400D for an external barometric sensor which I also add to a programmable pin on my unlocked 9A4). You can then enable fuel pressure compensation based on line pressure or injector pressure which then feeds into the fuel pressure Compensation Site Map and Compensation Map where the % adjustment of fuel is mapped to the pressure input.

[Shortshift]

But, if I understand correctly James, one of the important points here is that the MBE ECU supplied as standard on the car by Caterham is encrypted/locked and whilst one or two people (Steve Greenald, for instance) can reprogram these most tuners and rolling road operators are unable to - so you need to purchase another ECU, potentially another 9A4, but in an unlocked condition so that it is ready to accept a new tune.

Happy to be corrected if I'm wrong but I think this is correct - I wouldn't want people to think they can add functionality to their 'standard' Caterham-supplied ECU without a bit of effort or expense.

James

[Mark w]

I may have confused with my terminology and also led by what I was told after Jim had his car upgraded .

Jim added paddle shift to his car which necessitated a new 9A9 ECU and a separate " box of tricks " supplied by MBE . My understanding is that the 9A4 doesn't facilitate the functions needed for paddle shift.

The new ECU was pretty expensive then it need the remap . As part of the remap a fuel pressure sensor and wideband lambda was added . 

I have an unlocked 9A4 on my car and when I enquired if fuel pressure sensing and pump control could be added I was told no . I didn't double check at the time but this is what I was told 

"No the unlocked 9A4 can not control the fuel pump.  It was a direct replacement for the OE ECU allowing full access to the CAN information but by accident we found out during this build that the 620 fuel pump is just turned on by the OE ECU at a set voltage. No control.  The 9A9 has high side power output which can control the voltage to the pump.  It also has the ability to run wideband Lambda which is also needed for the upgrade."

maybe that's wrong and an unlocked 9A4 would do the same if paddles are not required ? 
if so I feel my next project has appeared on the horizon ...... 

[aerobod - near CYYC]

James, that is correct, you need an unlocked 9A4, currently £545 plus VAT at SBD or similar prices elsewhere. If you want to get the best out of both Easimap and fine tune for your car's unique requirements it is well worth the investment.

One of the best additions is to add is a wideband lambda sensor such as a Bosch LSU4.9 with a digital controller that feeds into the MBE 9A4 (I've installed the Innovate LC-2 in my car: https://www.innovatemotorsports.com/products/lc2.php). With your own wideband lambda system installed, you can road tune the car quite safely, based on data logging from Easimap.

I have kept my original 992 ECU (fitted to the R400D until Caterham changed to the evolution 9A4) and the narrow band lambda sensor, it takes about 10 minutes to swap out my 9A4 and wideband sensor to revert back if necessary. I did have to do this a few years ago when I bricked the 9A4 due to Windows hanging on my laptop just at the critical stage of uploading a new map, had to send the ECU back to SBD for a factory reflash that cost one hour of their labour. SBD declared that I was extremely unlucky on when the Windows hang occurred, as it was in the middle of writing the small communications code block to the ECU, anywhere else in the write and I would have just been able to redo it.

Mark, the 9A4 doesn't control the fuel pump pressure, only the pump relay, but can adjust fueling based on the pressure value. The 9A4 is thus fully capable of adjusting fueling based on fuel pressure (which is usually the important need), but not the pump pressure itself. The ECU code releases are always adding new features, so some years ago this may not have been possible with the 9A4, but it is now.

[Mark w]

Right 

we need to move this  ECU discussion to a new thread to protect Marks original discussion point .

Aerobod , your not by chance at Anglesey on Monday are you ? Wouldn't mind a chat ...

[aerobod - near CYYC]

Sorry Mark I'm based in Calgary, Canada so Anglesey is a bit of a stretch for me especially with COVID restrictions ;). I do occasionally camp at Church Bay there, though, my childhood family vacation spot that we sometimes return to.

[Mark w]

well I am , hopefully , in Canada next year , I best come and see you !

 

[CtrMint]

Had 30 mins in the garage this evening.  Drained the coolant from the radiator and pulled the top hose off.  I'm pretty confident there isn't space to fit the thermostat housing.  My motivation is rapidly disappearing, rather than getting annoyed, I'm just utterly utterly disappointed.  Sooo soo just want to let rip here! 

[ScottR400D]

It’s just another example of poor CC design and support, in my view.  

It’s straightforward, I guess, either reach for your lawyers, because the car really isn’t fit for purpose, or fix it yourself like most of us seem to have to do sooner or later. 

What about the crude method of partly blocking the rad until the system developed by the other guys has been proved when you can fit that?

if I sound unsympathetic, I’m really not, having been through a similar issue myself with my diff, an issue that’s costing me over £3.5k to fix, again because CC appear unable to engineer things properly. 

CC, “The owners care so we don’t have to”?

[CtrMint]

I found blocking the rad didn't work particularly well, it only added a few degrees to the operating temps.  I suspect most likely because the problem isn't due to the cooling capacity of the rad, but the fact the thermostat is forced open regardless, and even without huge amounts of air passing through the rad, the temps in the rad creep down anyway.  The approach may work on track where the overall heat under the bonnet is significantly higher, but on the road and particularly on the island it just doesn't work.

I might be able to fit the PRT on the return side, there is slightly more space, well a different layout.  It will still be ridiculously tight down there.

 

 

[Mark w]

Mark

having looked at the space available ( and I've got remote damper slaves there as well !) I think your going to need some tight right angle hoses with intermediate connectors .

maybe cut from something like this ? 

[ChrisC]

Or, and I know this is difficult to hear, actual take the car back to the dealer so the dealer / manufacture can look at the problem. 

Every time I have had a car exchanged, my first step in the process was to return the car to the dealer, where the faults was diagnose, and agreements reached.  I didn't discuss the problems in public, or on forums.    In all cases, admittedly sometimes with a little struggle, a settlement was reached.  

Now I know the problem is known, so diagnosis is a mute point, but the dealer must be permitted to see the car.  

I also can't understand the position taken on the CC modified thermostat fit, yes its untested, but its approved.   If there are more complications due to its fitting, your CC warranty is still intact.   Fitting your own thermostat is equally as untested, but doing so absolves CC of any warranty obligations.  Even draining that car and removing the top hose would have implications for cooling system warranty, because an argument over air locks when refilling would be valid.   CC does read this forum. 

Outside warranty, the re-instatement of the standard Duratec bypass looks like the way to go in my book.  

[CtrMint]

Thanks Mark, 

I DHL'd some angled fittings from Viper Performance, they should be here today.  They are a guess, but again just trying to maximize my options and chance of success.

[Doctor]

Bypass work all done. Test at Anglesey on Monday.

[CtrMint]

Chris see post #42 the botched thermostat which CC are pushing onto owners has not worked, it's just slowed the response.   I'm not going to spend >300 quid for a ferry, plus hotel accommodation, risk of covid, then 14 days in quarantine on my return home, for CC to force the same workaround on my car.  Plus Oakmere has frankly been a disgrace over it, denying there is a problem, or any customer has ever raised such an issue. 

[CtrMint]

Just to clarify, I'm not saying no to the bypass, this thread was about me trying the PRT approach, as I have confidence issue wrt removing the intake etc.  

[ChrisC]

Botched maybe, but approved it is.   

You have the tools, and you have proven your car cools whenever the RPM is over 2250 (ish).   If you take the fix and prove its still not fit for purpose, the ball is in your court.   You could even tell them that's how your going to test it. 

The location challenges where always present, considering and the industry standard is about 97 faults per 100 cars, or put it another way, almost all new cars will have a fault.   I can't imagine CC is better than the industry standard, so you always where taking that risk buying a brand that's not represented with a dealer on the IOM.

As for your dealer, I can't comment.  However a long time ago I took great delight accepting a bankers draft for my money back on a new Golf purchase, where the week before the Dealer Principal call me a "F**king C**t, and I would never get my money back". 

Covid has affected many, 14 days quarantine is a small price to pay.  

[Doctor]

No worries, I hope you figure it out. Theoretically there is no reason why it shouldn't work, it is a bypass in a way. I'm just not sure about the two stats in the system. 

[ScottR400D]

#42 

In all honesty, I can’t imagine CC are in any way close to the industry standard, whatever that is. 

I’m amazed that you’d suggest someone spend hundreds of £ just to prove a fault that everyone knows exists. 

The onus is on CC to fix the issue, properly and permanently, for them to do the testing and research and make the product fit for purpose.

They might surprise us all but I won’t be holding my breath........

 

 

[Doctor]

Scott, I'm not sure I follow. I'm not suggesting anything to anyone. I've always been fixing the shortcomings or designs flaws on Caterhams myself, this one is no exception. I needed a solution for my engine overcooling issues now, not in an uncertain future. We do think our two approaches will yield a usable result and I have no issues whatsoever talking to CC and show them everything I've done - it is very straight forward. I would like to thank Mark for sparking this debate. It has been a discussion I have thoroughly enjoyed.