ChrisC

Never tried a GPS speedo, all I know its they are not IVA compliant.

I love the questions on this product, Q "Is It GPS" A "No"

The purplemeanie coolant hose section shows a hose that didn't exits on my 360R / 420R, its described as the "Recirculating Hose", and appears to connect to the block near the thermostat, however all the duratec thermostats I have seen have two connection, one for the bottom hose and one for the T hose. That said, its a good starting point. The 360R has the addition of the oil/water cooler near the oil filter. The hose that runs between the heater and the T in the purplemeanie diagram needs to go via that oil cooler. Ironically I think the 420 has more space because you don't have to run coolant hoses to the oil/water cooler, which in my car was further complicated by the washer bottle being under the plenum, and the crank case breather is deleted in the 420. I also found it very tight around the thermostat with an S3 and the 103C stat.

I think you have to wait for the warranty outcome. Don’t forget you have a new to most of us rad design, so even if there was a known problem it might not apply. For what it’s worth I only know of the plastic capped Sigma rads being prone to leaks, but that’s it.

Sounds like the standard way of fitting the cover. I used dual lock instead of Velcro to make it a bit more secure. Don’t forget your IVA trim on the edges.

Fit the FRAM for now and enjoy the weather

I believe “crap” might be a harsh word, I believe they will perform perfectly adequately providing service schedules are observed, which doesn’t look like that’s going to be a problem for you ;-). I just believe better quality exists without a significant addition outlay. I would love to line up all the contenders, cut them open and make up my own mind.

If you believe YouTube and the oil filter comparisons, Fram isn’t the best quality oil filter on the market. Was the WH77 the original oil filter? If it was I think would source one of those.

This is a long shot because its not diff related, but my car had terrible rattle from the rear because of the combination of pads and new (non Ford reconditioned) rear calliper. I had Delphi pads due to having 4 pot calipers at the front. It was easy to diagnose, the rattle would stop when braking, and you could feel the outer pad had play in the caliper event through the wheel, with the handbrake off. I only started having the problem when my leaking rear calipers where replaced under warranty, with post 2017 spec items (as fitted to your car). I changed pads and anti rattle springs without success. Eventually a simple tweak of the spring on the pad sorted my noise. PS they would also make a noise when the wheel was rocked back and forth, but not to the same extent, do your same test as per the video, but put you finger on the outer rear pads

One easy and minor thing to check is the screws holding the plywood floor aren’t fowling the diff / carrier. One of mine touched the diff, which meant I was left with two options move the screw or (and what I did) file down the screw so it cleared, its only a self tapper. For what its worth, my opinion is the noises you have are normal. As far as I can tell all the knocks are coming when the car is on very light throttle and the speed is more of less constant, i.e. the engine is not accelerating or decelerating the car. I bet you will find examples that make more noise, and some make less. I suspect this is because the BMW diff is modified for the Caterham. Significant amounts of metal are removed from the original BMW casting, and I assume this means the diff is stripped before that machining takes place. Then it’s reassembled with either the open or titan LSD internals by the Caterham supplier. How much care and attention to detail that’s applied to this reassembly is the real question. Although not faulty, I.e. within Caterham’s acceptance criteria, I suspect a noisy diff rebuilt by a specialist can be improved.

The 620R have a very different relay and switch system to a standard 310R, that said the 620R switches are an option on the 310.

I am no relay expert, but I suspect the relays used aren’t the highest grade component on the market, so its a simple supplier QA / component failure. To melt a relay you have to go some, so a fuse will normally go long before a relay fails.

Your links look fine to me, as per late 2015 spec, i.e. no spacer/boss. That looks like the ARB has been dragging on the ground to me. I guess it takes a combination of factors, like the corner, passenger etc.

Duplicate

The upper column bush may come with the column if you have a steering column lock like this one https://caterhamparts.co.uk/columns/5484-upper-steering-column.html. In which case I wouldn't remove the steering wheel and use that to pull the top bush out. Also make sure the steering lock is off :-)

Even stones get caught between the wheels and the de Dion tube / ears. Scratching the inside of the wheel.

So initial thoughts, have you checked you exhaust tip and seat bolts. Scrapped my seat bolts a few time with no significant visible damage. The exhaust tip is well know, I have seen some race cars had a D shaped exhaust after excessive scraping.

TSK all the way, he seems to have a fixed price list, I guess that’s from all the years working for CC. I have had nose cones painted before but can’t remember the price, but last year I had back panel £150, rear arches £80 each, and a few patch repairs (from brake fluid damage on the side panel near the master cylinder) £30 each. This was a metallic paint. From memory nose cone with nose band and no join was about £160 ish, so £400 for a nose is steep in comparison. TSK was cheaper then having the paint protected.

So you have radial calipers, therefore the calipers pictured on Jackwebb Motorsport’s website won’t fit.

Looks like where the baffle is welded, if it’s leaking then talk to CC about the warranty issue.

Also the pictured calipers won't fit cars post 2014, when Caterham made the switch to radial mounted front calipers. Looking at your profile picture this might be a problem for your car.

Can you post a photo of the TPS, its on the throttle body. Problem is the pictures on the CC parts website are not clear if there is adjustment in the TPS or if its fixed position. It looks likes this. https://caterhamparts.co.uk/throttle-cables/5792-throttle-body.html?search_query=620&results=160 The TPS is the black bit with the wires coming of it. On the 420R the ECU is always powered (unless you have a battery isolator switch), one way I have found to reset the ECU throttle site without adjusting the TPS is to disconnect the battery. A better way is to use CC own software, but that's not an option. Worth a try, obviously not as easy having the battery in the passenger foot well.

Problem with the 620 is its to new and most (if not all) are maintained by specialist or CC themselves. Therefore this community is going to be just guessing at your cars problem. Jonathan is correct disconnecting a lambda sensor has been used many times to get Sigma cars home, but will that work on a 620? Even your code reader may or may not me helping. The normal Caterham Duratec ECU is a MBE 922/9A4 and this doesn't give meaningful OBD codes, even to Caterham. It does give live data so you can see components working (or not). So what ECU does a 620 have? However when I googled the P0120 code and saw TPS sensor I though that is possible, but it went down hill from there, i.e. EGR faults and Inlet heaters faults makes me think this information isn't helping. From the Caterham Parts web site (not my Lego 620R) the ECU is listed as a MBE 9A4, which means anyone local with Easymap and the MBE Lead can see and record your live data from the ECU. This will show you if most of the sensors are working or not. I would also check the obvious still like the plugs to see if the problem is isolated to a single cylinder, and coolants / oil for loss or contamination, just in case.

It is, and same PM applies Chris.

PM Sent