Camotubebender
SILVER Star
Moving around to get sound differences
Reving
Some notes on what I noticed, including things I discovered later compared to the progression of this story (and also suggestion made in real time by people on insta):
View attachment 3506362
- Sounds propagate through all the engin and transmission and can be heard coming from everywhere
- Clearly the strongest in the half rear of the valve cover, sounds stronger on the right also but it may just be that there are a lot of obstruction on the left side...
- Tried all the combinations of clutch-in/out, in/out-gear (with transfer in N) to check if it could be the pilot bearing or throwout bearing but it changes nothing and it's not where the sound is the strongest.
- PCV valve got mentioned, I couldn't fully removed it by hand and was not wanting to risk to destroy the casing/seal using a tool, looked ok to me and I don't think the sound comes from here.
- No blow back
- This sound only appear after the engine gets really fully hot, driving offroad for some time or over a mountain pass (which is exactly what I expect to do all the coming days...). Just idling indefinitely or driving casually on road is not enough for it to appear. When it appears it generally stays for the day, a 45min-1h lunch break is not enough for it disappear, needs 2-3h cooling for that.
My current theory would be the valves clearance that got wrong (last time set 12000km ago) or was not set hot enough...
Haven't 100% pointed the issue to this day so definitively taking opinions on it.
(once out of the Atlas it's rare that get into a condition it appears)
That PCV valve is bad