Oil Leaks

Following the 10CR I developed several oil leaks, front seal, head gasket (push rod side) and rocker cover, all fairly standard but the strange thing was my engine had always been fairly leak free.

In a flash of inspiration sat on the front wheel staring at the engine drinking a cuppa, It suddenly dawned on me that I had modified my air intake system and that maybe it was having more of an effect than I had realised.

I connected a pressure gauge up to the dipstick tube and started the engine. Sure enough a small vacuum as expected as my breather system is plumed into my intake plenum upstream of the throttle bodies.

Took it out for a drive around town, still the same, slight depression on the engine. Found a nice quite road and increased the speed, at around 50 mph light throttle my gauge started to show a positive pressure in the crankcase, not good.

I pulled over and connected the pressure gauge directly to the intake plenum upstream of the throttle bodies in place of the engine breather and went for another drive, what I found was quite interesting, when travelling over 50 mph on light to half throttle I was registering a positive pressure in the intake system, good for performance bad for my breather system. Bearing in mind that on the 10CR (while on the autobahn), we could easily sit at 110+ mph on very light throttle, who knows how much pressure my crankcase was seeing, no wonder it developed oil leaks.

To sort the cause of the leaks I have decide to connect my breather system to the engine side of the throttle bodies and used a PCV valve to make sure it doesn't suck my oil out. I have cleaned up the engine bay and now await suitable weather to take it out for a run.