Before reading further, I'm no mechanic, but my answer would be...
Wait for it...
Both of them.
Looks like its an N55 engine (straight six with a turbo charger?).
The larger one is your main coolant reservoir
The smaller one is a completely seperate secondary coolant system.
All way too compex for me to properly understand. My engines just the less complex N46 workhorse. By comparrison looks as though yours is a thougherbred racehorse!
I believe that both of them use the same coolant but get that confirmed by someone else first as mine only has one cooling system.
All the best,
Shaun.
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Shaun
Responses are not meant as a substitute for professional advice. Answers are intended as outline only the advice of a qualified professional with access to all relevant information should be sought before acting on any response given.
The N55 is an engine for Mtech level cars such as the 335i and the Alpina.
Its a 3.5 litre staight six twin turbo (no wonder it needs two cooling systems!). Not quite the S class engine of an M3 but the sort of car that wouldn't be laughed at taking it to a race track open day.... Or if anyone is laughing you would be looking at them in the rear view.
Kudos Joanne, Kudos
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Shaun
Responses are not meant as a substitute for professional advice. Answers are intended as outline only the advice of a qualified professional with access to all relevant information should be sought before acting on any response given.
The N55 is an engine for Mtech level cars such as the 335i and the Alpina.
Its a 3.5 litre staight six twin turbo (no wonder it needs two cooling systems!). Not quite the S class engine of an M3 but the sort of car that wouldn't be laughed at taking it to a race track open day.... Or if anyone is laughing you would be looking at them in the rear view.
Kudos Joanne, Kudos
Oh its only a 3l Tw Turbo. Hoping my mechanic man can help in the morning or its off to the expensive rob you merchants garage. Or a taxi to collect said coolant and DIY! (dangerous). So annoying though - not been shopping yet and not much food in the house! Certainly not enough wine and chocolate to keep me from being grumpy.
-- Edited by Cheshire on Sunday 19th of January 2020 07:43:45 PM
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Joanne
Winner of Bookkeeper of the Year 2015, 2016 & 2017
Thoughts are my own/not to be regarded as official advice,which should be sought from a suitably qualified Accountant.
You should check out answers with reference to the legal position
Spot on there Shaun re the reservoirs and yes they both take the same coolant (which of course has to be propritory branded!). Actually the dealership filled them both up, checked for leaks and re-set the on board computer system, all for Łnil, so apart from wasting a couple of hours in their posh coffeee, biscuit/cakes/fruit filled comfy chaired (almost a soft each!) waiting area its all done and dusted. I might just wander back there when Im out and about and fancy a coffee, lol.
__________________
Joanne
Winner of Bookkeeper of the Year 2015, 2016 & 2017
Thoughts are my own/not to be regarded as official advice,which should be sought from a suitably qualified Accountant.
You should check out answers with reference to the legal position
