J80s

Member
I was driving back in my Series III when I noticed the temperature gauge which is normally low shoot up to the highest setting and I got a bit of a burning smell. I pulled in and there was lots of steam coming from the front grill and brown water pouring out from the bottom of the engine. I checked the radiator and couldn't see any water so topped it up to full.

I waited a bit and started up again and drove on, a few miles from home, and at first it was fine, temp low, but then it started to rise again and I noticed the charge light coming on occasionally, then regularly, then staying on. The temp gauge went to the max setting again and as I pulled in at home I saw again steam coming from the front and water coming out below.

As I looked at it properly in daylight: there seems to be a steady trickle of water coming from the bottom of the radiator where the pipe leaves it. I'm trying to see if it's coming from the radiator itself or where the pipe meets it but the clasp/screw is corroded on so can't easily get it off. Fan belt is fine, can't see any other obvious issues. Any ideas what might be the issue here? Really need to get back on the road at least for short journeys so any solutions of temporary fixes much appreciated.
 
Buy a hose set with jubilee clips from Craddocks and fit them and see if that's cured the problem. If it's still leaking it's the radiator most likely. Hoses and clips aren't expensive. The middle hose is a right fiddle to fit but worth doing them all.
 
What's inside the radiator itself that could leak, i.e. if it's not just a loose or damaged hose going from it externally what might be the problem and how hard a fix would that be?
 
If the water pump isnt working the engine would overheat, boil the water and throw it out of the system via the blow off pipe. This would normally go to the expansion tank if you have one. The Charge light might suggest its the belt not turning the alternator or waterpump.
 
Don't jump to conclusions, have a really good look and work out where the leak is before you start spending money.
Are you sure that it was the charge light and not the oil pressure light?
 
Yes it was the red light on the right with 'charge' written over it - it was going on and off then just stayed on - what does that mean? The fan belt seems to be turning when I look at it with the engine running. If it's not a loose hose, why else would water be pouring out the bottom of the radiator?
 
You need to be systematic when you try and work out what has happened, the first thing is to work out why it has lost water, has it boiled up and puked its water out, or has it leaked water and got hot because it has lost its coolant?
My first word of caution is that leaks often appear to come from the lowest point as this is where water naturally drains to, so dry everything off and have a really good look. It is possible that it has boiled up and overflowed through the cap and the water that you see at the base of the radiator has drained from the top or overflow pipe.
Secondly if your charging light has come on, is the fan belt tight enough? The water pump and the alternator are both driven by the fan belt, I would check the fan belt before I did anything else as if the fan belt slips the water pump won't work and the engine will overheat.
 
Yes it was the red light on the right with 'charge' written over it - it was going on and off then just stayed on - what does that mean? The fan belt seems to be turning when I look at it with the engine running. If it's not a loose hose, why else would water be pouring out the bottom of the radiator?
Although it may turn when ticking over or revving whilst stationary it could be slipping under load when driving. Check for belt tightness and check the alternator hasnt become loose on its hinge bolts or adjuster bolt. If its slipping its neither turning the alternator or the water pump efficiently.

Water always pours out the bottom even if the leak is at the top. Its called gravity. :p
 
Thanks, I'm going to have to get in there to see what's happening more clearly. Presumably even if there is an issue with the belt there is still a leak too, otherwise it should be holding water right? And I presume the reason you suspect the belt rather than just a leak is because of the charge light?

I'm kinda stuck for some short runs until I get this fixed- do you think I could get a way with a 2 to 3 mile run with a light load as it is?
 
If its the belt, you wont be charging the battery and cooking the engine wont do it any good. Will no doubt lead to head gasket problems. :(

If its not holding coolant when at rest then there is obviously a leak in the system. If its only when hot and running, theres a fair chance the boiling coolant is pressurizing the radiator cap and pouring out of the small outlet just above the rad caps seal. This normally goes down a tube to an expansion tank in a series 3 next to the rad and if this overflows down a second tube from this tank to the floor. The series 2 generally goes straight from the rad cap down a pipe to the floor. The tank on the 3 has the advantage of a siphon that returns the excess coolant back to the rad when cool.
 
You do not say if it is petrol or diesel, however running an engine whilst it is overheating is the best way of blowing the cylinder head gasket or worse.
Before you do anything check the fanbelt for tightness. There should be about 10mm deflection in each direction along its longest run. The engine will not cool properly if the belt is slipping, no matter how much water is in it, nor will it charge the battery.
As for the water loss, the radiator filler cap is spring loaded, if the pressure gets too high for example when the engine has boiled up then water will get past the seal and vent via the small pipe at the neck of the filler.
Is water leaking from the radiator when the engine is switched off?
 
Thanks, I'll check that. Yes water leaks out from the bottom even with the engine switched off, so it's simply not holding water, which has got to be an issue regardless of what's happening with the belt. It's a diesel and has an expansion container which seems to be remaining half full no matter what happens.
 
A half full tank is a good sign.
Obvious places for leaks then are the hoses and connections followed by the radiator matrix itself. My series held out for about 12 months without the addition of radweld that the previous owner must have been regularly dosing. I ended up just replacing the whole radiator as it was shot.
 
Also check the rad cap, if it's knackerd it won't hold pressure and as soon as radiator gets worm it overflows
 
Also check the rad cap, if it's knackerd it won't hold pressure and as soon as radiator gets worm it overflows
 

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