Chapter 7 with a Caterham SVT

[redursidae]

Good news! The fuel has stayed in the tank since the Autocross, and what was dripping didn’t smell like fuel, instead some sort of glue or residue in the underside of the aluminum shelf.

 

Since cleaning the shelf and the tank as best I could this hasn’t returned

 

As far as overall fuel smell, it is much better. I only smell the breather doing its job when I slosh the tank on a spirited drive and it subsides after some cruising.
 

Decided to do an LED swap with tail lights and indicators from Just Add Lightness, and headlights from Summit Racing. The headlights leave a little bit to be desired in their beam pattern but it’s decent. The tail lights are good and bright as needed. The indicators have not worked well so far, and cause all the lights to panic! With only one indicator on, all of the car's light flash, including the gauge lights. If I turn the lights on, then the buzzer is constantly on and the indicator bulb is lit. That’s a first. I tried disconnecting the tachometer to test the theory that the telltale could be the cause, but no dice, and not really sure where to go from here. This issue only happens with the LED indicators installed. Here is a video of the behavior with only the right indicator on:

 

 

 

 

Another interesting new quirk is that while driving with the lights on I can hear the buzzer and see the indicator bulb light up intermittently as I hit bumps. This is making me think there is a bad ground somewhere. 

[JohnCh]

I had something very similar happen with the Westfield many years ago. It turned out the ground on a rear taillight was bad. 

[Vovchandr]

Did you swap the flasher relay for an LED friendly one too? (JAL sells one I think but they are very easy to source anywhere)

Edited 4 hours ago by Vovchandr

[redursidae]

1 hour ago, JohnCh said:

I had something very similar happen with the Westfield many years ago. It turned out the ground on a rear taillight was bad. 

 

Good to know. One of the original tail lights was working intermittently before, so I will start looking around there. Any idea if missing reverse and fog lights might have something to do with this?

 

47 minutes ago, Vovchandr said:

Did you swap the flasher relay for an LED friendly one too? (JAL sells one I think but they are very easy to source anywhere)

 

Yep, I did. The car already had an LED relay, and I also tried JAL's relay to be sure.

[JohnCh]

1 minute ago, redursidae said:

Any idea if missing reverse and fog lights might have something to do with this?

 

I don't know how the loom was set up in those days. I wouldn't expect it to matter, but it's always possible that the grounds were daisy chained and the connection at one of those missing points failed (e.g. they crimped those grounds together to complete the circuit and the crimp weakened over time). My understanding is that because LEDs draw far less voltage, they tend to expose weak grounds earlier than an incandescent bulb. I'd start by replacing the incandescent lights one at a time to see if the issue persists or goes away as a means of potentially narrowing down the location of the issue. You may get lucky. If not, then start methodically checking and cleaning all the ground connections in the circuit until you find the culprit. Don't forget to hit the grounds at the switch and relay.

[Croc]

The loom was essentially a crossflow loom with a custom engine harness for the zetec.

 

I bet this is a bad earth somewhere.  John's comment on LEDs exposing bad earths is spot on.  

[redursidae]

Understood, and thank you. Will inspect the grounds.