Mikep
Active Member
Well I'm never too proud to admit when I have been a complete and utter plonker and I do sometimes have a habit of jumping to the worst case scenario but I discovered yesterdays cause of the dramatic temperature rise in my engine and it was directly related to one fundamental component of a coolant system.......... the coolant itself, or lack of it! It was VERY low, about 2 litres to be exact
I decided to check the operation of the water pump first so removed the blanking cap on the rad (the pressure cap is on the expansion Bottle) and when I looked into the radiator I couldn't see the water level :shock: I was expecting it to be flush with the top because my expansion tank had some coolant in it. I already had some mixed up so started to top it up and I reckon I had to put about 2 litres into it :shock: I ran the engine up the temperature and waited for any air to 'burp' out. I left the car ticking over for about half an hour and the temperature gauge stayed firmly in the centre right between the 8 and the 5
I will admit that since fitting the expansion tank I would check the level in that and assume all was well, evidently it wasn't. I fitted the tank as per other members cars but always found that if I topped it up to the line it would drop and be sitting just above the bottom inlet pipe after a run. Talking to some SD1 owners they too exprience this and even went so far as to fit a catch tank to collect the coolant that was forced out of the expansion tank overflow. Quite clearly my expansion tank wasn't feeding into the rad and over time the water level has dropped :? This was one of the main reasons for fitting the tank as I was having to frequently top up the radiator and assumed this was due to coolant coming out of the vent (I will say that I am not aware of any coolant leaks and even after yesterday there isn't any evidence of head gasket failure). How often would I expect to top up the radiator without a tank fitted?
Upon advice and the practicalities of it I fitted the expansion tank as low as possible but it doesn't seem to feed into the radiator so what I have done is fit the pressure cap back on the rad and the blank one on the tank and will monitor coolant levels. While I was poking around with the engine running I noticed that the water pump pulley has a slight wobble backwards and forwards as you view it side on like it isn't running true :? Could this be a case of it not being mounted properly or wear inside the pump itself? I did put a screwdriver to it and put my ear to that and had a listen and it sounded ok, there was a consistant ticking nosie, obviously the impellor turning but then I have nothing to compare to, should this noise just be a whirring sound and the sound of coolant rushing through?
I decided to check the operation of the water pump first so removed the blanking cap on the rad (the pressure cap is on the expansion Bottle) and when I looked into the radiator I couldn't see the water level :shock: I was expecting it to be flush with the top because my expansion tank had some coolant in it. I already had some mixed up so started to top it up and I reckon I had to put about 2 litres into it :shock: I ran the engine up the temperature and waited for any air to 'burp' out. I left the car ticking over for about half an hour and the temperature gauge stayed firmly in the centre right between the 8 and the 5
I will admit that since fitting the expansion tank I would check the level in that and assume all was well, evidently it wasn't. I fitted the tank as per other members cars but always found that if I topped it up to the line it would drop and be sitting just above the bottom inlet pipe after a run. Talking to some SD1 owners they too exprience this and even went so far as to fit a catch tank to collect the coolant that was forced out of the expansion tank overflow. Quite clearly my expansion tank wasn't feeding into the rad and over time the water level has dropped :? This was one of the main reasons for fitting the tank as I was having to frequently top up the radiator and assumed this was due to coolant coming out of the vent (I will say that I am not aware of any coolant leaks and even after yesterday there isn't any evidence of head gasket failure). How often would I expect to top up the radiator without a tank fitted?
Upon advice and the practicalities of it I fitted the expansion tank as low as possible but it doesn't seem to feed into the radiator so what I have done is fit the pressure cap back on the rad and the blank one on the tank and will monitor coolant levels. While I was poking around with the engine running I noticed that the water pump pulley has a slight wobble backwards and forwards as you view it side on like it isn't running true :? Could this be a case of it not being mounted properly or wear inside the pump itself? I did put a screwdriver to it and put my ear to that and had a listen and it sounded ok, there was a consistant ticking nosie, obviously the impellor turning but then I have nothing to compare to, should this noise just be a whirring sound and the sound of coolant rushing through?