L200 (mk5) overheating issues

[richy_B]

Hello,

got an intermittant overheating issues I want to put to the masses.

 

L200 mk5, 2009, 2.5 diesel. Just hit 100k.

 

So about 2 months ago I was driving in. There is a point about 5 minutes from my house where the truck reaches normal temperature- I know this exactly as this is where I switch on the heater in the winter. I glanced down at my temp guage and it was stone cold. Bit odd so I watched it for another 20 seconds and all of a sudden it jumped from cold to normal. Not gradual, just nothing to middle in a blink.  Stopped and check it all over, levels seems fine etc. Carried on, nothing different for another week and few hundred miles.

 

Week later I was on the motorway and the temp started to rise. Got towards the red so I stopped. Check it all over, left it 5 minutes and restarted. All fine again for a week and few hundred more miles.

 

I was due a bit of maintenance so did the timing belt and tensioners, new water pump, new thermostat and coolant. I thought the temp issue might be a sticky thermostat.

 

A week after it got hot again. I stopped and this time the expand tank was bubbling over and steaming out the over flow. I let it cool down and found the coolant had dropped loads. Lost about a litre. Refilled with 50/50 mix and carried on. Fine again for 2 week or so. I thought i'd give it a test so when I had my multione trailered behind and a reasonable steep uphill on the M40 - dropped it down to 4th gear and really pushed it. Within 10 seconds tue temperature rocketed and when I stopped it was bubbling over from the expansion tank. Let it cool and topped up.

 

I am thinking it's the head gasket but I'm not seeing anything else Is associate with it - the oil seems clean, no milky aspect. Same with the coolant, no oily residue. No smoke from the exhaust etc. 

 

I have not seen any drops or obvious leaks under the truck so I don't think it's a spilt hose split. 

 

The thermostat seems to be working fine. cold one side of the unit the. once the engone has been on for 5 minutes the other side heats up.

 

Radiator fins seem clear and nothing that would hinder it. 

 

I'm going to run it into the local place and get them to test the head gasket. 

 

Any other thoughts?

 

 

 

 

[Stubby]

Flush the rad through . Could be partially blocked .

[Dave177]

Had virtually the same problems with a ranger recently. Flushed the coolant system with a 2 part rad flush then put a new radiator in. Runs completely fine now 

[richy_B]

Thanks guys. I'll give the radiator a good flush out then go from there. 

[Stubby]

5 hours ago, richy_B said:

Thanks guys. I'll give the radiator a good flush out then go from there. 

It may need a new core .

[richy_B]

1 hour ago, Stubby said:

It may need a new core .

how would I know? will it be hard to flush through? 

[Stubby]

6 minutes ago, richy_B said:

how would I know? will it be hard to flush through? 

If flushing through does not fix the situation then maybe the core is still blocked or collapsed etc .

[Lust4life]

It's worth getting a sniff test done to rule out blow by on head gasket. Heads seem a common issue on L200s

 

top and bottom hose should get hot and be squishy but not collapse. The rad should get hot all over. When you flush it do not use tap water. Use de-ironised water as it's stops furring up of rad and pipes.

[richy_B]

Update. Flushed the radiator myself and put a new radiator cap on. Seemed ok, nothing obviously coming out from flushing that shouldn't (fragments, rusty bits etc. 200 miles later I noticed it getting hot again. Topped it up with about 200ml of coolant. 

 

Put it into the garage for testing. They did a compression test on the system and apparently all normal. They don't suspect the head gasket. No obvious signs of coolant leaks anywhere. 

 

Going to get a new radiator in. It's about £150 but it'll eliminate that at least. 

[Leyburn Lad]

On 27/09/2018 at 07:34, richy_B said:

Update. Flushed the radiator myself and put a new radiator cap on. Seemed ok, nothing obviously coming out from flushing that shouldn't (fragments, rusty bits etc. 200 miles later I noticed it getting hot again. Topped it up with about 200ml of coolant. 

 

Put it into the garage for testing. They did a compression test on the system and apparently all normal. They don't suspect the head gasket. No obvious signs of coolant leaks anywhere. 

 

Going to get a new radiator in. It's about £150 but it'll eliminate that at least. 

Maybe wrong, but my L200 has similar issues, it turned out to be the egg valve leaking fumes back into the coolant system. It something to do with the Colling of exhaust gasses and the section becomes porous, this was on a 2005 model.