renault laguna1 2.2rxt - Laguna 2.2 dt overheating

Honest John Back Room » Technical matters
View Threaded
Mon 26 May 2014 22:41
renault laguna1 2.2rxt - Laguna 2.2 dt overheating - Zool

I have a strange problem with my 98 laguna 2.2dt, the car starts well, drives fine on the flat and has plenty of power when you put your foot down, the problem starts when I go to climb the mountain to my house, within about 500 yards the temperature shoots up and the overheat light comes on, the radiator fans kick in as they should but it's still not enough to lower the temperature, I end up having to pull over and wait until the temperature on the gauge goes down to about halfway before I set off again, 500 yards later I have to stop again this goes on until I finally make it home after about 5 stops, there's a smell of hot coolant when I stop with a small whisp of what I assume is steam coming from the reservoir cap but no other obvious signs of leaks.

I have a list of thing's to check including head gasket, EGR valve, turbo,waterpump and I also wonder if it might be an airlock after a coolant change, although it's an old car it's in good condition with lowish milage and is normaly problem free.

I'm tempted to pull the engine out and do a complete stripdown and rebuild to see if I can pinpoint the problem but before I go to such an extreme measure I wonder if anyone here has any ideas?

Reply | Report as offensive | Link
Tue 27 May 2014 18:27
renault laguna1 2.2rxt - Laguna 2.2 dt overheating - madf

Your car displays the symptons of a furred up radiator giving a cooling system which is marginal.

Or a fialed water pump.

Or a slipping drive belt to teh water pump.

Odds on the radiator...if it's original it is long past its design life, Easy test, when the engine ifs warm , feel the boottom of the radiator - with care.. If cold... that is the problem.

Reply | Report as offensive | Link
Tue 27 May 2014 21:51
renault laguna1 2.2rxt - Laguna 2.2 dt overheating - Fernando P

Near the top of my check list would be the thermostat, which may be unserviceable because of age etc and stuck in the closed position therefore not letting coolant through to the radiator.

Reply | Report as offensive | Link
Wed 28 May 2014 08:46
renault laguna1 2.2rxt - Laguna 2.2 dt overheating - madf

A stuck thermostat would give oeverheating on the flayt surely?

Personally I would replace the thermostat with the radiator (if it IS faulty).. as you say an old thermostat is likely to fail...

Reply | Report as offensive | Link
Wed 28 May 2014 11:23
renault laguna1 2.2rxt - Laguna 2.2 dt overheating - Fernando P

Madf - I guess that this is a case of "coolant neglect"!

Reply | Report as offensive | Link
Wed 28 May 2014 20:13
renault laguna1 2.2rxt - Laguna 2.2 dt overheating - Zool

mystery solved, the head gasket's gone.

I was bleeding the cooling system yesterday and started the engine without putting the res cap back on. exhaust smoke out of the cooling res straight away, not much but enough to tell me what's happening.

thanks for the advice I appreciate it, so now I have to strip the engine and get the head pressure tested not an easy task on the G8T motor thanks to the timing belt, at least I know what's gone wrong now and can do something about it.

Reply | Report as offensive | Link

Looking for a garage you can trust? Honest John's Good Garage Guide has thousands of reader recommended garages, plus how-to guides and tips on servicing.

The Good Garage Guide