Coolant Prob

[dazzler]

Hi, wondered if anyone here could give me any advice on my 3ltr. I keep losing water, but it's a wierd one and not at all sure what the best steps are to take.
After gurgling noises coming from the rad expansion chamber some time ago, I had the head tested and found that the head had gone. I had the head replaced and she was put back together.
After running it around for a while i noticed I was still losing water, at this point I had spent so much money, that
I could not afford to spend any more, lost my rag and parked it up. The truck has been sat on my dads drive for months, anyway, as there was no MOT on it, we took it for the MOT, which it flew through, then decided to get the water prob sorted.
I can not make head nor tail of it.

Temp gauge never passes mid-way
no white smoke
always starts excellently
runs and drives like a dream
no obvious leaks.....

...just loses water. Having never worked on a diesel myself before and being skint, i wondered if anyone had any advice for me as to
what i need to do to narrow down where the problem lies? Any advice would be much appreciated. Cheers.
Daz

[da SLUG man]

how much is it losing and where are you checking the level?

[dazzler]

how much is it losing and where are you checking the level?

Well, had someone take it to the garage for the mot for me and they drove with the rad cap off, after using 1/4 tank of diesel it had lost most of the water in the rad. Before when driving with the cap on, seemed not to lose too much, but still topped up after every drive.
Levelwise, we were just going by the fact that the rad took so much water!
Not too sure if we would have caused any damage driving with the rad cap off but someone had suggested doing that.
To be completely honest, until it came back from the MOT, I had lost my rag with the truck and it was looked at and driven by so many people, that it's not until now, that i am seeing exactly whats going on. I want to be able to sort it but need some advice on what to look at in what sequence etc.
Sorry if this is not answering your question very well.!

Daz

[NiftyNev]

Do not drive with the cap off.This will only cause more problems.It may simply be a small leak somewhere and an easy fix.A pressure test on cooling system will help find any leaks.A radiator specialist can do this test and shouldn't charge too much.

Neville

[TonyN]

With the rad cap off it'll just empty the water everywhere. Get it pressure tested, its the only way you'll know for sure. It'll show up any leaks in the hoses, or show the gasket/head is knackered.

Check the viscous fan is working, it should have resistance to turn when cold, it roars for a few mins after starting, then quietens down at normal running.

Check for airlocks after filling, the heater blowing cold is a good sign of air in the system, they sometimes need topping up a little next day after draining and refilling as the coolant settles down.

replace all the normal easy stuff, rad cap and 'stat first and then get it tested.

[M35A2]

I agree. What ever you do, don't drive it with the rad cap off!!! If that was a petrol you would have probably seized the engine. I had a very small hole in the neck of my Defenders radiator. You could only notice it leaking when it was cold. As it heated up, it evaporated leaving a coolant stain. Have you checked all the hoses? If you put the heater on windscreen demist, do you get the screen steaming up? Is the oil ok, not milky? Take the oil filler cap off the rocker cover and look to see if there is any whipped egg white in the rocker cover or under the cap. Is the header tank in good nick? Is the rad cap ok? When the engine is heating up try squeezing all the hoses to see if the system is pressurising.

Start her up and get to running temp. Turn off and listen to see if you can hear any steam noises coming from anywhere. Failing that take it to a rad specialist and get it pressure checked.

[dazzler]

Cheers for the advice, will check a few things over thats been mentioned this evening, (KO the guy that suggested running without rad cap!) and go from there. Looks like I should get it pressure tested then...may have to wait till the end of the month tho. Also, there was the test done on my rad when there was suspicion of the head gone, a chemical that changed colour in the event of engine gasses in the water, would it be better to get that done again first?
Really want it running perfect as it's a real looker with no scratches or dents and it flew through it's MOT and the garage said that you wouldn't believe that it was built 11 years ago! Only trouble is, may have to sell due to the amount I have spent on it since the head went.

[NiftyNev]

Here is a little project if you are handy with bits and pieces.It's a cooling system pressure tester that's cheap to make and works.

http://groups.msn.com/toyotasurf/nif...o&PhotoID=6808

It's made from a T-piece,Low Pressure Gauge (0-250Kpa),Tyre Valve and a couple of other bits.The gauge connects to the expansion tank hose and is clamped.A small compressor (or even a bike pump) is connected to the tyre valve and a pressure of 100Kpa applied to cooling system and pressure monitored.A drop in pressure indicates a leak somewhere.If pressure remains constant then all is ok.It could do with a pressure relief valve fitted but I have not done that yet so when pressure is released a rag needs to be held around the hose to prevent the coolant spurting out.It could also be used to check cooling system pressure while engine is running but without a proper relief valve then disconnecting when pressure is high and coolant hot may be a little dangerous and no recommended.

Neville