Forum:
Hiya,
once again I need some serious advice.Recently I decided to take out the thermostat in the cooling system of my truck (J-reg Fourtrak) because of over-haeting and some rather erratic readings on the temperature gauge.But that didn't cure the problem yet 
I suddenly seem to loose incredible amounts of water while driving as I have to re-fill the radiator every time after a drive.After checking the whole system I had to come to the conclusion that the cooling system seems to be fine without leaks or cracks in any pipes.
Yet even after short trips the system needs a refill...expansion bottle empty and even about 1-11/2 ltr missing out of the radiator and still no suspicious signs under the bonnet and no white smoke fromt the exhaust.Pump seems fine (at least there is plenty of signs of it working when I leave the rad-cap open) radiator seems fine and heater seems fine but I'm still loosing lots of coolant.Has anybody got any more ideas?
Cheers
It might be a cracked
It might be a cracked cylinder head. I had a similar problem with my Toyota Lucida MPV no real explaination why it was running through a couple of litres per trip.
Basically the hairline crack allowed water to get sucked in and then blown out as steam with the exhaust. The water system did not over pressure and the heat gain was masked by the heat transferred by the turbo which is water cooled on the Lucida...
A barstorial job which cost me £1500 on top of this the turbo died six months later and cost another £1400. Life with my Kenari has been somewhat less fraught so far apart from a roof leak which was fixed with some body sealer around the standard rubber washer.
double check oil
if you are loosing water check the oil for any white or brownish scum around the dip stick or the oil cap this is also an indication of a blown head gasket because the water and oil mixed together emulsifies into a creamy scum check also the rad for any oily deposips by rubbing it between your fingers (when warm or cold NOT scalding hot) hope this helps
tozz
Heated
Could be anywhere, cracked head, cylinder block, or radiator, water from a pin hole will spray onto the hot engine and evaporate leaving no trace.
1/ Drain the coolant and fill with water with drain dye obtained from builders merchants, run the engine and check for dye stains, this will be a good indicator as to an internal or external leak.
2/ Pressure test the cooling system with stain added, look for external leaks, put paper under the vehicle to find the approximate location, this will identify internal or external leaks. Core plugs are the obvious leakage point for external leakage, followed by head gaskets.
3/ With the system pressurised, and leaks evident, but not externally; remove all glow plugs, depressurise the system and get an assistant to crank the engine, water blowing out will identify an internal leak into a cylinder, this could be a cracked liner, head gasket, or engine block.
Basically a process of elimination, but when you fill the cooling system, ensure the heat control valve is in the hot position, if it is not the heater radiator does not fill, when you set the valve to hot water goes from the cooling system into the heater radiator. Raise the front of the vehicle slightly when filling, massage the radiator bottom hose, this removes air locks which may form.
This assumes you have checked the obvious such as the radiator cap, the bottom seals wear and allow water out, and a lack of pressure in the cooling system.
Erratic gauge readings are because the sensor is not in the water due to losing it, this then measures the temperature of the cylinder head's metal. As water expands it alters the sensors readings giving erratic readings.
Check your oil level
Check your oil level ergently. If it is higher than it should be you may have water in the sump. If this gets too high the oil pump will pick it up. Water is not a good lubricant! To be totaly sure crack the sump plug off, and make sur you get a few drips of oil out. It has been known for quite a lot of water to come out befor the oil finds it's way down...
Any veiws expresed in this thread by me are purely from my own experience, and (sometimes) falible memory. Hope my comments help, but please don't take them as gospel.
Any veiws expresed in this thread by me are purely from my own experience, and (sometimes) falible memory. Hope my comments help, but please don't take them as gospel.