Overheating 300TDI

Hi All,
I hope you had a good Landy weekend

i have a common problem with my 300TDI, suddenly it started to overheat. I was drivint on the motorway doing 50 and i saw water coming out of the engine bay, most probably from the breathing pipe of the tank?
since then the engine overheat and i cannot seam to find the reason for it?

the you think the head gasket can be the cause?

Thanks,

It 'could' be the cause but isn't a common issue.

The most probable is that the water pump has failed.
If you release the tension on the snake belt you can sometimes feel that the water pump is only spinning the outside pulley wheel.
They are relatively easy to change and not expensive to buy.


In my opinion is probably worth changing the 'P' gasket too

Great. Thanks a lot. Can we test the water pump in a certain way?

On my old 300Tdi, I had the P-gasket and water pump fail on it, albeit at different times. Both showed with rising engine temperatures and coolant loss, although the coolant loss was quite gradual on both.

Two other issues were a poor condition radiator which caused overheating but no obvious coolant loss and a failed plastic plug on top of the thermostat housing, which showed with a cloud of steam behind the vehicle when driving.

Thé problem is that i my overheating problem i lost something like 7 litres of coolant and now i need to fill it back up every time i drive and i rise in temperature immediately. So i do not know where to start investigating. The issue is that i cannot see any water leaking.

Ziva said:

Thé problem is that i my overheating problem i lost something like 7 litres of coolant and now i need to fill it back up every time i drive and i rise in temperature immediately. So i do not know where to start investigating. The issue is that i cannot see any water leaking.

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If you cant see any water leaking its going out of the exhaust side or into the oil ways. Common for the water pump to go & over
heat as said. You need to do a compression test id guess its cylinder no 4 between the pushrod tube & cylinder.
Is it chuffing round the back of the head at the bulkhead.

I had a pitted head and HG fail on my Disco 300tdi and found most of the water in the sump.

300 head gaskets failures were a thing back in the day, normally as coolant not been checked and the level dropping not being noticed until to late.

7 lts is a large loss of coolant, the 300 has a high position for the water pump so as coolant is lost the pump soon starts running dry and not circulating any coolant. Temp rises very quickly then. Needs a sniffer test a [ garage tool ] to see if combustion fumes in the coolant tank, although if leak is bad bubbles and ones nose will tell.

One of the first things I did with my 300tdi was fit a coolant level alarm. It's definitely worth considering doing.

I had a slight leak on mine. I topped up regularly and wasn't doing long trips so was not too worried about it. I did a small journey after checking my coolant level (was only doing a 7 mile journey). After about 3 miles the alarm sounded, which I thought was an issue with the alarm as I knew the coolant level was ok. I also noticed the temperature was higher than normal.

I stopped to check just in case and was shocked when my header tank was empty. I topped up with what water i had and I was only about a mile from Tesco so went and got some water so I could drive home. Filled up the coolant at Tesco and with the bonnet up i could see a very fine spray coming from the radiator. I started a very nervous drive home.

Every time the alarm sounded I topped up. I managed to get home with only a couple of top ups, but at least the engine didn't go into the red.

I got my kit off ebay. I think it was just under £60 at the time, which turned out to be money well spent. The kit included a range rover classic header tank cap (with the low level sensor), a small circuit board, audible alarm, light, push button switch and wire. I sometimes have the alarm go off if I brake hard or going over uneven ground, but I just consider this a system check.

Thank you all for your help and support. I decided after calling my Mecanic that spending 2000 pounds on a head gasket without even being sure that this is the problem to do some work myself.

On Monday, a friend of mine will come over and we will start trouble shouting:
1) check the water pump
2) check for leak that i did not find before.
3) check for white smoke on the exhaust

I think this is the safe and cheapest option. If you think about something else, please let me know.

have a save drive

I'm assuming you've checked the filler cap for emulsion?

Dont rule out your radiator - but the sudden start of the symptoms is different

To be honest, i am waiting for the car to come back, but for sure i will add the check of the oil condition. Last time is did not contain any water as far as i can see.

Dr Strangeglove said:

Land Rover Defender / Discovery 300tdi 200tdi Low Coolant Alarm + Cap PRC7925 | eBay

The alarm and Flashing LED work in conjunction with each other so there is no risk of missing the fault. A test button is wired into the circuit to allow piece of mind that the system is working. I just wanted to say I’m glad you’ve started making the Land Rover low coolant sensors after we...

www.ebay.co.uk

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Buy the loom from the same seller (34.49) and the cap separate (26.60) and save yourself a tenner.

Or this glue on kit for 33 quid, https://www.ebay.co.uk/itm/30505385...hRs9M+O2fxaN7Oycsy/fufi6V2|tkp:Bk9SR9ir0b3JYg

Lots of helpful advice above. That kind of coolant loss is huge, not far off your entire circulating volume. What do you mean by 'you saw coolant coming out of the engine bay?' You have a closed system so no breather pipe. As steam or as liquid water dropping onto the floor? How often do you check the level and what time period has the coolant disappeared in? If the 300tdi is like the 200tdi you can check if your water pump is working simply by checking if the heater is working.

Step 1 - Find the leak. you should see crystallised coolant if it's leaking externally. Check engine breather pipes for emulsification suggesting head gasket or cracked sump. It will be extremely obvious if you're loosing that much coolant over a short time period.
Step 2 - if the water pump is working. Check the radiator isn't blocked. This is common.
Step 3 - if you can't find any external leaks, the water pump and radiator is fine have a look at the HG.

If the vehicle is running hot do not use it until you've got to the bottom of the problem.

Dear All,
still waiting for my car to come back to my house to start the investigations but something my friend told we was the following:
« the temperature is rising after a few minutes of driving and we can see the water coming out of the breathing pipe«

do You have some advice on where to start my investigation based on the list above? Water pump?

thanks.

A 300tdi engine takes several minutes to 'warm up'.
You can start a cold engine and run it without any coolant for a short time.
Several people have told you not to use/drive the car as you could p[otentially cause a lot more damage to the engine.

Have you actioned what I said in post #2 of this thread ?

miktdish said:

A 300tdi engine takes several minutes to 'warm up'.
You can start a cold engine and run it without any coolant for a short time.
Several people have told you not to use/drive the car as you could p[otentially cause a lot more damage to the engine.

Have you actioned what I said in post #2 of this thread ?

Overheating 300TDI

Hi All, I hope you had a good Landy weekend:-) i have a common problem with my 300TDI, suddenly it started to overheat. I was drivint on the motorway doing 50 and i saw water coming out of the engine bay, most probably from the breathing pipe of the tank? since then the engine overheat and i...

www.landyzone.co.uk

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Thanks. Yes I have ordered a new water pump and new gaskets (for the pump). The car will not be driven as it comes back on the back of a towing truck tonight.