Fumes in the vehicle

[Bigal23]

I've been driving a 1981 transporter leisure drive conversion,with the air cooled 2ltr petrol engine, for a couple of weeks and I've noticed a low level of exhaust fume smell I can't see any breaks in the engine bay hatch seal and no apparent damage to the heat exchanger or pipe work.
Is this usual for this vehicle? May be a daft question but I'm new to this vehicle and any help gratefully received
Thanks
Al

[multisi]

Have you got any oil leaking out of engine and onto/into exchangers ?

[itchyfeet]

hole in the body perhaps
drilled for something or just rusty

[fazzer]

I had same problem with my watercooled hightop,everytime we went on a long trip within an hour our eyes were stinging.I looked everywhere around the van found a few manmade holes and covered then up but still problem was there,then recently took R&R bed out and there was a pipe that went through a hole into engine bay but all silicone had gone so resiliconed it and all seems ok.Have you checked seal around engine lid.

[Jeff J]

I think it may be your push rod tubes leaking, try posting in the mechanical section.