75ZT Community

Oh i wish this were true, but i doubt it

View eBay item 150471416349

Sterling KV6 maybe?

I did not know that some cars were fitted with two fans.
Some time ago I had a car which had one fan fitted but with the provision for an other. Then, in very hot weather, it began to get very near the boiling point I thought an other fan would help.
Fitted an other fan, just like the one shown,thinking it would be better.
This did not prove to be the case.When the car was not moving all was well but when traveling along the engine temp. was even worse.( The gauge was better than the Rover painted on type).
From this I concluded that all fans which are placed in front of the radiator are in the wrong place, they should be placed behind to suck air through it. This leaves the full area of the radiator to receive cold air when driving along, when the fan is no longer needed but allows cold air drawn in by the fan at low /stop conditions.
An other point, there is quite a number of fan motors which are failing, ( bushes worn out) Why ? when the cars are only stopped/ stood, running for a small % of the time.
My theory is that when traveling at speed the wind through the fin blades turns the motors most of the time and this wears the brushes down, even when not in use hence worn bushes.
This is just my thoughts, whay do you think?

My Rover 620Ti had twin fans plus Air Con.

parkdrive wrote:An other point, there is quite a number of fan motors which are failing, ( bushes worn out) Why ? when the cars are only stopped/ stood, running for a small % of the time.
My theory is that when traveling at speed the wind through the fin blades turns the motors most of the time and this wears the brushes down, even when not in use hence worn bushes.
This is just my thoughts, whay do you think?

What erodes and wears brushes away is running under power. If the fans were never run under power, the brushes would last more or less as long as the car. There's virtually no frictional wear between brush and commutator.
As to the frequent failure of the Mark 1 3-speed fan, that's entirely down to the continual use of the aircon system. The slow speed runs all the time the aircon is in Auto mode. Some people never use anything else year-long, year-in year-out. It's the way the brushes are arranged that causes premature wear of the slow speed brushes. The later 2-speed motors run excatly the same way, but are wired differently and fatal brush wear has yet to be reported on this system.

TC

My old 820 had aircon(quite rare) it was fitted with two italian made fans that only ran in series when the aircon compressor was running, i cannot remember if they ever went up to full speed even when sat in traffic on the soon to be built end of the M3 in 1993, now that was a traffic jam, i remember the outside temperature being 106f, it was 66f in the car, i wondered why i got some funny looks as aircon was very rare then.

Why havent car manufacturers learned from then, the car did 125k and the fans never failed it was 12years old when i finally changed it to my present car, changed but definitely not forgotten.

We have taken the very reliable fans from scrapped 800 series cars many times and used them to replace the power sucking viscous coupled types on the old Range Rovers. It never really crossed my mind before just how reliable these old fans were.
The complex fan control box on those fitted with aircon was the weak point, especially as the early ones were mounted such that they were subject to spray from wet roads.