Expansion / overflow tanks for the 350i
Discussion
Does anyone have / know where I can get the two tank (expansion plus overflow) system described below, without going back to a main dealer / TVR themselves?
I've had a 1990 350i now for some 4 years and, like many 350i owners, one of the biggest niggles has been cooling! Basically - the system was constantly under too much pressure and water was finding a way out of the weakest point (usually the fan switch sensor at the top of the radiator, the top of the expansion tank, or both). It's due to a pervious owner fitting the wrong tank I suspect - and always have.
I did have a story from a Classic Car mechanic that, having noticed the 2 metal cradles attached to the nearside bulkhead behind the wheelarch, I needed a steel one (custom made by TVR one presumes) but never quite believed him so didn't go searching one out.
However, I was recently at the BNG and came across a very helpful chap, who showed me the above and said he'd never had a problem yet. Basically, he explained that the expansion tank is fitted with a pressure cap which, once under pressure, the underside of it compresses to allow hot air and water into the smaller overflow tank beside it - via a pipe coming from the top of the expansion tank. Subsequently, as more water is required back into the system, it is effectively sucked back in as required (i.e. presumably when the engine is cooling after a run, the pressure reduces and the water drawn back up automtically??)
Grateful for any advice anyone can offer on this.
Mario
I've had a 1990 350i now for some 4 years and, like many 350i owners, one of the biggest niggles has been cooling! Basically - the system was constantly under too much pressure and water was finding a way out of the weakest point (usually the fan switch sensor at the top of the radiator, the top of the expansion tank, or both). It's due to a pervious owner fitting the wrong tank I suspect - and always have.
I did have a story from a Classic Car mechanic that, having noticed the 2 metal cradles attached to the nearside bulkhead behind the wheelarch, I needed a steel one (custom made by TVR one presumes) but never quite believed him so didn't go searching one out.
However, I was recently at the BNG and came across a very helpful chap, who showed me the above and said he'd never had a problem yet. Basically, he explained that the expansion tank is fitted with a pressure cap which, once under pressure, the underside of it compresses to allow hot air and water into the smaller overflow tank beside it - via a pipe coming from the top of the expansion tank. Subsequently, as more water is required back into the system, it is effectively sucked back in as required (i.e. presumably when the engine is cooling after a run, the pressure reduces and the water drawn back up automtically??)
Grateful for any advice anyone can offer on this.
Mario
Mario, have you thought about having them made? Maybe in stainless or aluminium?
I had some parts made by Lee at www.fusionfabrication.fsnet.co.uk/. Not that far from you I guess. You will need to be specific about what you want as he's not really into the design side, but does an excellent job.
I had some parts made by Lee at www.fusionfabrication.fsnet.co.uk/. Not that far from you I guess. You will need to be specific about what you want as he's not really into the design side, but does an excellent job.
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