was changing the coolant and fitting new RARB drop links and noticed that there is oil leaking from the TCT. The previous owner told me when he bought it that he removed and repaired the TCT in the past. Is this oil leak something to be worried about (could it cause damage) and how should this be fixed?

 

I noticed the o-rings on mine were flattened compared to a new part. It wasn't leaking yet but I think if I was to remove and reinstall, without replacing the o-rings, I could've seen a leak.

I think all you need are new o-rings.

 

I'm pretty sure it is leaking from above the TCT, and fluids don't normally drip upwards. I'd check the Vtec solenoid or the valvecover higher up, I think the TCT location is just the last collecting point.

 

What Jfusion said. 7/10 chance it's the VTEC solenoid, and hopefully it's just the filter gasket and not the top triangle gasket. Once that gasket starts leaking the only way to fix it is to buy a new VTEC solenoid.