Lancefitzgiben

To update this: I took that longer drive and got the car really and truly fully warmed through. The condition persisted, though not as dramatically. This is certainly new behavior, so nothing 'normal' about the extent of the temp swing. A bit of swing I could see, but this is a drop of like 20C. New thermostat is in the car, currently waiting on the temp sender, which I figured I may as well do while the system is drained again. I'll report back in a couple weeks - I miss driving the stupid little thing!

You can change them in the car (SV, anyway) - gonna be a job though. Main hurdle will be getting the torque-to-yield crank bolt out, and sourcing new diamond friction washers for crank/cams. Everything in front of the motor between the motor and next chassis tubes needs to come out obviously. In my case this meant the oil tank needed to come out. All in all it's not a bad job, just make sure you source all the critical parts such as the diamond washers, crank bolt, cam plate (tool) and timing pin bolt (tool) ahead of time.

Does anyone have a line on some fixed back composite seats? Just throwing it out there. I know they're available from Caterham, and Tillett USA.

The zipper put in by Soft Bits are pretty burly. No issues at all. I don't usually utilize them, unless the half doors are fitted. My car is an SV and I'm 6'1" but thin and pretty limber.

11Budlite, what's your home track like? If it's somewhat tight and technical I don't suspect that you'd have any issues - biggest issue is that a serious track car will be set up a good deal different than a useable street car. Even with my 485 and its 236 (call it 180 or so here at 7k ft above sea level) I hit a wall at 100mph, anything under that however and I have way more power than I need. Often more than I can use. For road use there's something to be said for a caterham with a bit less power and a lot less tire.

I've noticed, ever since I got my Caterham; that the clutch pedal is wobbly, and is able to move side to side by about as much as an inch at the pedal. Even though Caterham said that my car shouldn't have the bronze pedal bushings, I waited until they had some in stock and bought a couple, hoping that my car does use them and that mine was cracked.. Turns out my car (2014 485 SV) does use the bronze bushings, but the bushing was in fine shape. I pulled the pedal out and took it, along with the spacer and bushing to my machinist buddy. Upon inspecting the pedal assembly he discovered that during the welding process, the pivot bore of the pedal got pulled out of round. He's truing up the bore and making a new bushing with oilite bronze. So if your brake or clutch pedal have excessive wobble side to side, that could be your culprit.

Tony at Caterham said it's normal for the temp to drop some with rpm as it forces coolant through the thermostat. I'll go for a longer drive this weekend and see if things stabilize as the car gets fully warmed through; though I don't anticipate change. Going to order in a stat and sender in the meantime.

Temp does creep down when revved over 4k while stationary, but doesn't cool as quickly (no air flow?) Your theory about the extra flow forcing through a restriction was how I was making sense of the thermostat theory. I was thinking that maybe with lower rpm flow, coolant wasn't really getting to the radiator as much.. then some extra flow was forcing that cooler fluid into the system. Do I have more than the one coolant temp sensor that's on the back of the head? I'm not even sure how to verify the functionality of a sensor. - Tim

Hey guys, having a little issue with the cat. I was having a little leak from the water rail, as the coating on it was compromised and letting a bit of coolant out. That got air in the system and I had big temperature spikes. The water rail got a cerakote and we filled the system with an airlift. The car now warms up just fine (heater valve open) and temps act normal - until I exceed 4k rpm, at which point the coolant temp begins to fall off. If I'm warmed up (80c) and give it a squirt up to about 7,500 rpm, the coolant temp drops by about 15c. Once cruising again the temp slowly rises back to normal and stays, unless I use the upper half of the tach. General symptom searches indicate the thermostat as a possible culprit. Sounds logical enough, but I'm looking for some more opinions. I'd rather get the issue fixed with one more drain/fill, as it's been done a few times now. I'm guessing the other possibility is a sensor? 2014 485S dry sump, with heater, about 4200 miles.

Sure! This is the sort of input I'm looking for. Default is always Amsoil since I run it in other vehicles. I've already had to step out for the oil in the Cat, so I'm certainly not glued to Amsoil.

Hey guys, this has probably been beaten pretty bad but I've searched around and I'm still looking for an answer. I've got a 2014 485S, coolant is original so really needs to be flushed out and replaced. What's the default coolant? I do want to run an antifreeze mix as we get winters here. Amsoil antifreeze seems to be compatible so that's the way I'm leaning. Also, when it comes to bleeding and the heater, I know I need to fill and bleed with the heater circuit open - is there a protocol for when to open/close the heater valve during normal use? My coolant temps have been higher than normal and I suspect air - system hasn't been opened but that valve has been manipulated both warm and cold. Thanks for any insights - Tim

Justin, just saw this. Awesome R500! I've got a 485S, up on Los Alamos. How's ABQ treating you? Have you played around at Sandia Speedway yet? Any other tracks? There's a great casual car meet every Saturday on Jefferson just south of paseo near a Starbucks if you haven't found that yet - and a good monthly cars and coffee north of Santa Fe on first Saturdays. If you're on facebook look up the Los Alamos Auto Club, which I run. Hope to meet you some time!

Hey ultraslow, Tim here - I met you in traffic one day here in la while driving my blue caterham. Could you post some more symptoms etc? I run a very active and helpful auto club here in town and I'm sure we can help you get it going!

Hey guys. Been driving the car fairly regularly and it's now up over 1k miles. Running like a champ *knock wood* and seriously fun! Other than a coolant odor that pops up now and then, everything seems pretty happy.

To finish this up for anyone paying attention: The car is back together and everything went smoothly! I've gotten just about another 400 miles on it since the issue and the car is now formally broken in according to the caterham recommendation. I've been coming to adore this little thing, and can't wait to get it out on track this year.

Okay, Had a few more guys over today to bang heads and shoot ideas around. One guy ended up picking up the crank pulley to check out the way that the cps great is attached. Long story short, the three button head screws that hold that plate on were ground down, and one was backed out/quite worn. we'd forgotten about it, and hadn't given it much thought at the time - but that central timing cover bolt was beat up when we removed it.. I think that's the source of the noise. Whether or not there's something else that's making that occur; I'm not sure yet. Everything is in spec on the bottom end, and we did measure crank thrust. One potential is the lack of the forward diamond/friction washer on the crank - which is missing. I've got one behind the gear but there isn't one on the front. That can account for a bit of tolerance. How about the fact that it only happens warm? Is everything really expanding that much? Anyway, making progress.

Thank you! That could be some help

Pan is off and everything is super clean - as you'd expect. Does anyone have assembly specs and/or tolerances of a 2.0 duratec with cosworth internals?

Been out of the country for a bit - gonna be back on this problem soon. We're going to pull the pan next and inspect the bottom end; since the timing cover is off it's an easy job to pull it.

I know that oil loses viscosity as it heats up - but the car had been run many times to warmer temps and didn't display any odd noises. I'm at a loss at this point

Finally got the bolt out using a longer bar and someone standing on the brakes. Sadly there's nothing obvious behind the timing cover, so I'll spend some time reading and thinking. Oil viscosity was brought up by the shop who put the motor in. Good thought and possibly a contributor - but the noise popped up all of a sudden after 160 quiet miles.

Even with no oil in the motor? I've got push button start, so "bumping" is really really difficult.

Nope - still suspecting something behind the timing cover - but that crank bolt won't budge.

Yay crank bolt....

Put another qt of oil in just for grins, she sounded happy as a clam, even with some warmth - until I have her a couple revs toward 3k. Then the ticking commenced again. Oil pressure between 3.2 and 4.2 bar at idle. The 3.2 was with some more warmth in the oil.