Oil leak on top of gearbox (RS200)

[Meaterpillar]

Hope I can get some advise/ help:
Got a donor engine fitted and run-in completed but engine is eating oil, 3/6 dots of oil is gone (according to the oil sensor), just done 700 miles.

Can’t find a leak around all the gaskets but oil is collected on the top of gearbox, does anyone know what might be the possible issue?

 

[NorthloopCup]

I’d be having a look at the gasket for the coolant thermostat housing mate. It’s oil and coolant in that area, and when they leak, they leak pretty well.

 

[Meaterpillar]

I’d be having a look at the gasket for the coolant thermostat housing mate. It’s oil and coolant in that area, and when they leak, they leak pretty well.

I changed the thermostat recently, the coolant must have been leaked while changing. Do you have the part number of the gasket, thank you

 

[NorthloopCup]

I changed the thermostat recently, the coolant must have been leaked while changing. Do you have the part number of the gasket, thank you

I’m afraid I don’t know the part number for the gasket mate