Omega Owners Forum

Omega Help Area => Omega General Help => Topic started by: luizvivas on 14 October 2019, 15:12:18

Title: REPLACING VISCOUS PROPELLER BY ELECTRIC FAN
Post by: luizvivas on 14 October 2019, 15:12:18
Before installing the turbo kit, I had the viscous propeller removed and decided to install a 16-inch electric fan instead. A second temperature switch was mounted on the upper radiator hose. Now the two electric fans work independently, each with its own switch. Using a relay, this new fan continues to run for some time to lower the temperature after the engine is turned off. With this modification we gain space, because the fan is much thinner than the propeller. The pressurization of the turbo to admission passes right there.

VISCOUS PROPELLER:

(https://uploaddeimagens.com.br/images/002/374/678/full/2wgsnsg.jpg?1569435587)

ELETRIC FAN 16":

(https://uploaddeimagens.com.br/images/002/374/684/full/30hyp7k.jpg?1569435676)

ADDITIONAL TEMPERATURE SWITCH:

(https://uploaddeimagens.com.br/images/002/374/693/full/xfnor4.jpg?1569435832)

FAN INSTALLED:

(https://uploaddeimagens.com.br/images/002/374/704/full/n2k1ed.jpg?1569435935)

APÓS A INSTALAÇÃO DO TURBO:

(https://uploaddeimagens.com.br/images/002/408/517/full/IMG_20191009_110731596_optimized.jpg?1570651379)


Title: Re: REPLACING VISCOUS PROPELLER BY ELECTRIC FAN
Post by: Bigron on 14 October 2019, 17:27:06
Yes, well worth doing. Several years ago I had problems with the viscostatic fan on mr Carlton, so I replaced it with a Kenlowe electric fan and temperature sensor just like yours - it was great! Also, the mpg improved as it only came on when neederd, not all the tine.

Ron.
Title: Re: REPLACING VISCOUS PROPELLER BY ELECTRIC FAN
Post by: ronnyd on 14 October 2019, 18:06:28
Yes, well worth doing. Several years ago I had problems with the viscostatic fan on mr Carlton, so I replaced it with a Kenlowe electric fan and temperature sensor just like yours - it was great! Also, the mpg improved as it only came on when neederd, not all the tine.

Ron.
Had a Kenlowe fan fitted on my auto Mk 3 Granny when i got a tin tent. Was far better all round. :y
Title: Re: REPLACING VISCOUS PROPELLER BY ELECTRIC FAN
Post by: Raeturbo on 14 October 2019, 19:56:29
Not to mention the few horses gained :y
Title: Re: REPLACING VISCOUS PROPELLER BY ELECTRIC FAN
Post by: Diamond Black Geezer on 15 October 2019, 01:05:46
I did that once...car got upto temp, whereupon the switch section exploded under pressure from the hose, spattering hot coolant everywhere.

It was not a very good quality job,  :D
Title: Re: REPLACING VISCOUS PROPELLER BY ELECTRIC FAN
Post by: Andy B on 15 October 2019, 09:01:13
I did that once...car got upto temp, whereupon the switch section exploded under pressure from the hose, spattering hot coolant everywhere.

It was not a very good quality job,  :D

I fitted the switch to the rad in a spare blanked off threaded boss when I did the same to my Senator
Title: Re: REPLACING VISCOUS PROPELLER BY ELECTRIC FAN
Post by: Bigron on 15 October 2019, 09:48:50
My Kenlowe one had a bourdon tube, the bulb of which went into the top hose radiator end and the tube itself (very thin)  was in a rubber "saddle" thing at the clamp point, to prevent leakage. The far end of the tube operated the thermostat.  :y

Ron.
Title: Re: REPLACING VISCOUS PROPELLER BY ELECTRIC FAN
Post by: LC0112G on 15 October 2019, 10:42:47
Before installing the turbo kit, I had the viscous propeller removed and decided to install a 16-inch electric fan instead. A second temperature switch was mounted on the upper radiator hose. Now the two electric fans work independently, each with its own switch. Using a relay, this new fan continues to run for some time to lower the temperature after the engine is turned off. With this modification we gain space, because the fan is much thinner than the propeller. The pressurization of the turbo to admission passes right there.

Yes and no. What this does is lower the temperature of the water in the radiator. What it doesn't do is lower the temperature of the water in the block/head, because there is nothing pumping the cooler water around the engine after shutdown. The effect is called "Heat Soak", and it can cause the water in the block to boil after shut down. On the Carlton, and specifically the Lotus Carlton, this causes the cylinder head gasket to fail, usually around cylinder #6. AIUI the other 24V Carltons can also suffer from cracks in the cylinder head valve seats to water jacket.

The Lotus solution was to include an auxiliary electric water pump which comes on when the engine temp exceeds 98 degrees. Unfortumatley they also included a 3 way valve to 'switch' it in/out of circuit, and this valve is vacuum operated. Leaks in the vacuum pipework mean the valve switches out of circuit so the pump ends up pumping into a dead end. This is the cause of many LC engine issues IMHO.

The engine looks like a 12V, so perhaps it's less of an issue than on the 24V/LC but before you go boosting it's probably worth monitoring the water temps around cyl #6.
Title: Re: REPLACING VISCOUS PROPELLER BY ELECTRIC FAN
Post by: Nick W on 15 October 2019, 11:32:51
My Kenlowe one had a bourdon tube, the bulb of which went into the top hose radiator end and the tube itself (very thin)  was in a rubber "saddle" thing at the clamp point, to prevent leakage. The far end of the tube operated the thermostat.  :y

Ron.


you would have to pay me to use one of those again. Every one I've seen leaked, wasn't consistent, lacked durability, looked shit and cost much more than it was worth.


Now I always use OE switches, preferably in the radiator if it has a suitable boss but will fit them elsewhere. Ian's X30 engined MGB will use a V8 radiator(with an unmodified Omega tophose :o ) with a boss in the radiator that will cost £20 to have soldered in. On my 2.9 Capri engine I welded the boss to the thermostat housing, and used a Peugeot three pin switch to control the Sierra Cosworth(actually a later DOHC radiator and fan setup that was the same but a fraction of the cost if money changed hands) fans. It very rarely needed the second fan. Many switches use the same M18x1.5 thread that O2 sensors do, so I have the tap to make that easy.
Title: Re: REPLACING VISCOUS PROPELLER BY ELECTRIC FAN
Post by: Bigron on 15 October 2019, 11:51:20
I don't have your wide experience, Nick, so I can only speak for the one I fitted on my old Carlton, which performed perfectly with no leaks. I do agree about the price though - about £100 as I remember, some 30 years ago.  Mind you, the fan seemed powerful enough to propel the car along all by itself!

Ron.
Title: Re: REPLACING VISCOUS PROPELLER BY ELECTRIC FAN
Post by: Nick W on 15 October 2019, 12:04:50
I don't have your wide experience, Nick, so I can only speak for the one I fitted on my old Carlton, which performed perfectly with no leaks. I do agree about the price though - about £100 as I remember, some 30 years ago.  Mind you, the fan seemed powerful enough to propel the car along all by itself!

Ron.


I should probably admit that I wouldn't bother replacing a viscous fan on a standard installation any more. An engine driven fan in a well fitting shroud is much more effective than an electric one.
Title: Re: REPLACING VISCOUS PROPELLER BY ELECTRIC FAN
Post by: luizvivas on 15 October 2019, 15:46:05
The viscous propeller of my car lost efficiency about 10 years ago. Here in Brazil, when this happens, most decide to lock the propeller, so that it rotates next to the engine, especially the owners of Omegas 2.0. Theoretically it improves cooling, in a country where the temperature most of the year stays above 30ºC and mostly produces a cool sound, kkkkkkkkkkk. The replacement for the electric fan was motivated by overheating caused by a short circuit that stopped the auxiliary electric fan in the air conditioner. The locked propeller proved unable to cool the engine by itself, running in the city. The car's dashboard was disassembled, the 27-year-old wiring defect fixed. The locked propeller is like the air conditioner on all the time and without it there was a noticeable performance gain. The two electric fans have been running together for 2 years without problems.

 :y