Engine stalling when oil tank cap removed.
- Thread starter keithwren
- Start date
les richards
Member
Thought that was quite usual on that engine - certainly a drop in revs, if memory serves at least.
Hi,
The revs and engine speed are supposed to drop a bit when you take the cap off - you are in effect introducing a vacuum leak by doing this that causes air to bypass the metering unit and therefore weakens the mixture. All quite normal.
I wonder if therefore you already have a similar vacuum leak elsewhere and maybe the idle mixture is setup in a way compensating this, then when you remove your cap there's just too much air bypassing the metering flap to lift it much?
Others could possibly be (and easier for a mechanic to set for you);
- Already weak mixture?
- Metering disc is off-centre in the metering head and needs centralising....
Run this idea by the engine builder. There's also an old Porsche document on the internet somewhere showing areas for consideration regarding air leaks. There's quite a few though!
Good luck.
The revs and engine speed are supposed to drop a bit when you take the cap off - you are in effect introducing a vacuum leak by doing this that causes air to bypass the metering unit and therefore weakens the mixture. All quite normal.
I wonder if therefore you already have a similar vacuum leak elsewhere and maybe the idle mixture is setup in a way compensating this, then when you remove your cap there's just too much air bypassing the metering flap to lift it much?
Others could possibly be (and easier for a mechanic to set for you);
- Already weak mixture?
- Metering disc is off-centre in the metering head and needs centralising....
Run this idea by the engine builder. There's also an old Porsche document on the internet somewhere showing areas for consideration regarding air leaks. There's quite a few though!
Good luck.
Which engine
I remember mine doing similar, initial speeding up then often progressing to a stall.
Posts made and opinions expressed are those of the individual forum members
Use of the Forum is subject to the Terms and Conditions
