Faint burning smell, what could it be ?

Hello,

I recently took my van around Wales for a test drive and on a couple of steep hills that went on and on and then on some more I was aware of a faint burning rubber smell. The engine was getting pretty hot and the electric fan I added was definitely necessary to keep it below 95 ( when the alarm goes off ).

At the tops of the mega hills I pulled over and opened the engine cover to let it have some fresh air but the smell was gone by then. My van is a 2.8 3L engine automatic and isn't a fan of hills but it manages, however these particular ones were a bit much so something was starting to cook and going up the hills from a low speed ( 20mph limit in towns ) didn't help.

All ideas about what it could be welcomed, thank you.

I used to have the same van and mine was exactly the same when travelling in Wales. I never found out what it was, but it didn't seem to cause any issues.

Thank you, that is very reassuring to know. The only thing I can think of is that my expansion bottle has no breather pipe ( just a hole ) and on a steep incline with very hot water going in there and raising the level some splashed out and hit the engine. The water level was very slightly down so that might be it, other than that all levels were normal and if some rubber was burning I would've thought that the smell would've stayed around a bit longer.

Finger's crossed it's probably just a Welsh hill/ mountain thing as you suggested. I know now what to be aware of and I'll put the fan on earlier than when I suddenly realise something is a bit more than a slope and has been going on for quite a while.

We’ve Toyota Hiace 2.5 diesel auto(no turbo)
I’ve been smelling, what I’m thinking, the burning smell you’d get from an overheating house appliance plug … a kinda fishy smell ??Defo a burning smell.

Comes n goes???

That's electrical maybe it's time to start sniffing wires, relays and connections ! The smell should still be there and probably wafts around when it gets hot. I don't know this from a Hiace point of view but from past experience with old electrics they still smell even if they're not on, it's just not in the air.

Happy sniffing !