QUESTION
Driving my Lotus Elan Sprint back from Cowra today it was pretty hot and it seems it got a lot of heat soak.
The engine water temperature hovered around the 90 to 100 degrees and inside the cabin was just like an oven.
Above 90 deg the fans kick in but the constant 3000rpm with two on board, long-drawn hills and express-way driving etc kept the water temperature up.
At the time the ambient temperature was hovering around the 28 - 31 degrees Centigrade!
In still air, it is usually a tad cooler so I'm still scratching my head as to why it was running hotter!
You can usually tell when the car is hot as the gear leaver and the steel tunnel are very warm.
Radiator etc is pretty well blanked off to direct all the incoming air through the radiator.
My Elan Sprint cooling system is still marginal despite the following list of improvements -
Waterless coolant
4 core copper radiator
Twin electric radiator fans
71 degree centigrade thermostat
Tooth belt driven water pump and alternator
Can you offer any advice as to what might be causing the water temperature to run so high?
D.R. - Pennant Hills, NSW
ANSWER
The symptoms you describe are typical of a water pump efficiency or cavitation problem.
It is recommend that the water pump be checked to establish it delivers a 400mm minimum head of water and the coolant should not be aerated.
If the water pump impellor blades or the spacer ring (adjacent to the impellor) are corroded then the pump will cause cavitation.
For further information about checking water pump efficiency, see the article here
Copyright © 2015 Lotus Marques
Driving my Lotus Elan Sprint back from Cowra today it was pretty hot and it seems it got a lot of heat soak.
The engine water temperature hovered around the 90 to 100 degrees and inside the cabin was just like an oven.
Above 90 deg the fans kick in but the constant 3000rpm with two on board, long-drawn hills and express-way driving etc kept the water temperature up.
At the time the ambient temperature was hovering around the 28 - 31 degrees Centigrade!
In still air, it is usually a tad cooler so I'm still scratching my head as to why it was running hotter!
You can usually tell when the car is hot as the gear leaver and the steel tunnel are very warm.
Radiator etc is pretty well blanked off to direct all the incoming air through the radiator.
My Elan Sprint cooling system is still marginal despite the following list of improvements -
Waterless coolant
4 core copper radiator
Twin electric radiator fans
71 degree centigrade thermostat
Tooth belt driven water pump and alternator
Can you offer any advice as to what might be causing the water temperature to run so high?
D.R. - Pennant Hills, NSW
ANSWER
The symptoms you describe are typical of a water pump efficiency or cavitation problem.
It is recommend that the water pump be checked to establish it delivers a 400mm minimum head of water and the coolant should not be aerated.
If the water pump impellor blades or the spacer ring (adjacent to the impellor) are corroded then the pump will cause cavitation.
For further information about checking water pump efficiency, see the article here
Copyright © 2015 Lotus Marques