White smoke that appears when driving on the circuit. The conditions for it to occur are consistent: after about 3 laps at Sodegaura, when I return to the pit and the engine idles, a considerable amount of smoke billows out. When I start moving in this state, it puffs out heavily, then after driving a bit, the smoke stops, and when I return to the pit, the same thing happens again—it’s a repeating cycle.
I didn’t like being prompted by the marshals to check, even if it was just a precaution, so I previously installed an oil catch tank. When first installed, it caught a little mist, but before I knew it, nothing was accumulating in the oil catch tank, and the smoke kept billowing out…
When I traced the blow-by hoses, I found oil contamination around the grommet of the breather chamber below the PCV valve. When I removed the PCV valve and blew air through it, it did allow airflow, but it required quite high air pressure to pass through. So my theory is that the air was leaking from the grommet before the PCV valve could open, preventing the mist from rising above the PCV valve (to the catch tank line) and causing it to return, resulting in white smoke.
The breather chamber itself was no longer available as a part when I inquired, but the grommets, joints, and hoses were still available, so I ordered everything.
To remove the breather chamber, I accessed it from below. You need to remove the intake manifold support, which requires a fairly long extension. And it’s tight. The piping also needs to be removed, but the space is extremely cramped. After removing the breather chamber, I first cleaned it thoroughly, then removed the completely hardened grommets and joints by breaking them apart. Reassembly is just the reverse procedure, but it’s quite tight. I also replaced the oil seal between the breather chamber and the engine, of course.
I connected the hoses to the new grommets and joints, positioned them at an angle that would make connection as easy as possible, then returned everything to its original position, connected the hoses, and tightened each bolt. Writing it out makes it sound simple, but accessing everything is really difficult because of the cramped space and all the parts and hoses in between.
Using various gripping tools, I managed to complete the installation. Removing the engine oil filter would create a bit more space, so if I ever have to do this again, it would be best to do it together with an engine oil change.
This time, I combined the hose from the breather chamber to the PCV valve and the hose from the head cover to the air cleaner hose into one, bypassing the PCV valve and connecting directly to the oil catch tank. The piping from the oil catch tank to the outside was routed to the underside of the car instead of connecting to the intake manifold.
I capped off the intake manifold.
When I tested this setup at Sodegaura Forest Raceway, there was no white smoke at all, even after continuous laps or when returning to the pit. I had a friend follow me to check, and they confirmed the same thing. Even the marshal who always used to give me warnings said, “No smoke at all today!”
When I checked the oil catch tank, a few milliliters of mist had been caught, which made me grin. The joy of finally solving the white smoke problem that had been a concern for so long, combined with the pleasure of being able to push hard without worry, made for a very enjoyable day.
