Lots of questions !

[AndyT]

I posted this to the Se7ens list as well but the more the merrier !

 

The car spec is: '97 1.6K Supersport with widetrack, ap brakes, LSD, 6spd box, lightened flywheel, uprated clutch, apollo tank and it's done almost 28K miles

 

1) After doing Magny Cours last weekend I notice now that it looks like the radiator header tank has leaked with water streaks over most of the engine. Is there an easy fix for this ?

 

2) I'm getting really fed up of not being able to get over speed bumps without either the exhaust hitting or the sump scraping (this is even after adopting the 0.0001mph 45 degree approach) The car doesn't have adjustable platforms so can't be raised without the fitting of those. Any ideas of cost for the parts & setup ?

 

3) Oil temperature: Normal running on the motorways at around 80-90mph was giving a reading of around 90-100degrees. On track it was just out of the red which suggests 120 degrees ? Is this acceptable ?

 

4) Oil pressure: Normal running at 60mph was giving a reading of 4bar, running at a constant 95'ish mph was giving a reading of 2-3bar. On track when the oil was reading 120degrees the pressure was going down to around 1bar. All these reading were taken while under load and not at idle. Is this acceptable and if not what can be done about it ? (btw now I'm running Mobil

1 Motorsport it seems to give higher pressure readings than the Comma Synthetic stuff that was already in the engine)

 

5) Brakes: After a 10min hard session the brake pedal travel seems to increase from almost nothing to around 2 inches of travel. Leave the car for 20mins or so then go back out and the pedal is crap (still too much travel and not much braking ability) however after 2 brakes or so the pedal becomes

rock hard and then carries on as before until the end of the run when it goes soft !? At no time does it feel like the brakes are going off or suffering fade it's just the pedal travel is further (which doesn't help when trying to heel 'n toe)

 

6) (This is going to be hard to describe but hopefully you'll catch my drift) After getting an uprated clutch fitted last week I've notice some sort of shunt in the transmission when accelerating in 1st gear. It almost feels like the rear wheels move back a tiny amount when accelerating fast.

 

7) Where the water rail attaches to the head, above where the solenoid is, was leaking. When the car was at Derek Moores I got him to check it out whilst doing the clutch. He said that it should've had some sealant on the join but there wasn't any. He put some sealant on and it looked like it had fixed the problem. However it still looks like it's leaking to me. Any

thoughts ?

 

8) After a while when on track the rev counter seems to get a mind of it's own and seems to wave between 5 & 8K revs. To be honest I tend to drive by engine note and shift light so it's no big deal, however would like to know if this is a common problem or not !?

 

9) I'm based in Sevenoaks, Kent. If I wanted to take the car somewhere to someone that could just drive the car and say "no they all do that" or "ahh.. yes that's a such and such problem" where could I go ? I really would prefer to go to someone other than Caterham for financial reasons and always prefer giving my business to a smaller outfit or ideally find some knowledgeable friendly fellow se7ener that would be interested in taking a

look around ;-)

 

Many thanks for reading all this and sorry if half/all these questions have been asked before !

[Alex Wong1697456877]

1. Get your cap pressure tested. Can't remember what the release pressure should be off hand though.

 

2. I'd be careful of affecting the handling just for the sake of having to crawl over speedbumps. Personally, I use 14" wheels on the road. I have a set of adjustable platforms for sale, but they may have gone to someone else pending bargaining etc.

 

3. Not really. Modern synthetics should be able to tolerate this but it's getting close to the limit.

 

4. This is very worrying! Are you running a dry sump? Are you getting oil surge?

 

5. Your brakes need bleeding (and maybe some racing brake fluid eg Castrol SRF)

 

6. Don't know. What sort of clutch is it? Is it only when you accelerate from standstill?

 

7. Don't know

 

8. Check all your ignition connections. This could be the first sign of an electrical problem. Are you hitting the rev limiter? This will cause the rev counter to do strange things as it cuts the spark to a cylinder making the rev counter miscount the number of sparks and revs.

 

9. Don't know.

 

I didn't do very well in this test did I?

 

Alex

[AndyT]

1) OK.. thought surely a replacement cap wouldn't be much dosh ?

 

2) I don't mind crawling over them.. It's just that even though I crawl over them the exhaust scrapes and occasionly the sump scrapes too

 

3) So what can be done, and why is it running so hot then ?

 

4) No dry sump just the Apollo anti-cav tank. Oil surge ?

 

5) Bled the brakes after the last time I got the problem. It made no difference when back out on track. There's Dot4 in there at the moment, was going to upgrade to Dot5.1 or AP600 fluid but was told the brake feel wasn't so good

 

6) Uprated Caterham item. Only seems to be apparent when pulling away

 

It wasn't a test smile.gif

[Jason Plato]

1 - New header tank or cap

2 - Nothing you can do about speed bumps other than either avoid them or raise the height - what is your clearance beneath the sump at present ??

3 - Asuming the oil temperature guage is reading correctly , you could consider an oil cooler with a thermostat to maintain a constant 90ish C ??

4 - Your oil pressure ( again assuming the guage is reading correctly ) is VERY low . I would check the oil level , you should be maintaining about 4 bar at a constant 80ish mph dropping to 2 bar at hot idle . If the oil level is correct then you could have a problem with the engine , I would get it checked out by a specialist - depending where abouts you live .

5 - This is far from normal particularly as you have AP brakes .I would re bleed the brakes , if this fails to cure the problem then a close inspection of the whole system is required before you end up in trouble .

6 - Dunno . Who fitted the clutch ??

7 - As alex said .

8 - Have a chat with some fellow club members in your area , they will know .

 

Dave

[Asklepios]

Andy,

5. Don`t just bleed the brakes but change out all the fluid.You are probably suffering old fluid which has absorbed moistue ,which is coming out of solution as a gas when your brake pads are dumping heat to the fluid.Bleeding just removes the obvious bubbles,leaving "contaminated "fluid to repeat the process when next thrashed.

Do not be put off trying Dot 5.1 or 6. Do not,repeat not try silicone dot5.

 

You can always revert to dot4 if you are unhappy,but bet you don`t.

 

[Jason]

Andy

 

Look at "Yet More R500 Parts for Sale" in for sale

 

Jason

[Tony Martyr]

7. Is that the one about the water header leak?

Derek et al seem to just use sealant for this joint but there is a standard Rover gasket that is made for it and if coated on both sides with Hylomar will fix the leak for good. I had exactly the same problem with the same streak down the starter. Now all fixed. When you go to the Rover dealer it help to have a photo of the header - the Rover car item does not look the same but it uses the same stange gasket with a sort of rectangular hole.

PS you a feeding the oil temperature paranoia. I blame dual temp switches supplied with the Apollo tanks. How many people pulled in off the track to cool down when only coolant temperature was displayed? It is a very good thing that LSD oil temp isn't shown or we would have even more to worry about

[EFA]

Andy,

 

Get to the North Kent meeting on Tuesday night. They'll be plenty of advise and the opportunity to possibly swap a few bits to ensure your guages/rev counter are giving correct readings.....

 

 

 

Fat Arn

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