Engine: D5: Volvo V70 D5 185bhp 2006 Mystery Coolant Leak

[petey]

At the moment, you're driving the car and it's getting hot and at some point, coolant is leaking out. So long as you're constantly ensuring the degas bottle is always topped up, you won't have any long term problems. However, be aware that wherever this liquid is leaking from, it will corrode what it finds in the way so please make sure you wash the area down if you think it's leaking.

I would drive it till it's hot and have a good look around, sniffing for the distinctive odour of antifreeze. If it is a pin hole then it'll only be apparent when it's cooking hot.
Turn the cabin temperature down, leave the A/C on and get it (the cooling system) hot.

[Max HEADVROOM]

an easy thing to do is buy a cheap ebay ultra violate leak kit.. just pour the dye in the header tank and look for leaks with the torch .

[Thassos]

I have the same year D5, and also had a coolant leak some time back (couldnt seem to see from where tho..) until some poking around on a small hose (see first pic) that runs around the front of the engine (see the split_pipe pic attached - was where mine was leaking from) simply caused by vibration chafing on the hose on the corner of the round thing!

The coolant also flows through the aluminium larger dia pipe, and if you take a look at the back of the engine (hard to see easily) there is a donut through which coolant also flows (uloop pic), the alloy loop can move and with vibration wear eventually leading to a hole in it (another place it could be leaking from). UV dye is another way to see where the leak might be coming from, but suggest you have a look here first as it could just be one of these places...

[TurboDiesel2006]

Thank you for all the comments.

I put everything back so I could re-start the car and get it hot. The car is currently on axle stands with its nose pointing in the air so I can get underneath. I started the car and when warm ran it at higher rpm to get it hot. I then inspected from the top and underneath.

1) the temperature gauge is fluctuating and the fan is on almost constantly so I guess I have missed re-connecting a connector somewhere.

2) the air-con condensate pipe is dripping a lot but I put that down to it being humid and the air-con is on.

2) When I crawl underneath I can that coolant is running along the underside of the EGR Cooler to the rear collar and then dripping off onto the mesh covered heater? hose. I can see coolant between the rear of the mesh and the hose.

3) I cannot see any signs of leaks from the two hoses on the top of the EGR Cooler.

4) I replaced the EGR Valve with a new unit about 15 months ago. I did fit a new gasket between the Valve and the cooler.

So is it likely that the EGR Cooler is the culprit. Do these fail and if so how? I thought the coolant went in one hose and out the other and it is sealed in that the gasket sealed the turbo exhaust gases not coolant.

[S60D5-185]

Originally Posted by Thassos

I have the same year D5, and also had a coolant leak some time back (couldnt seem to see from where tho..) until some poking around on a small hose (see first pic) that runs around the front of the engine (see the split_pipe pic attached - was where mine was leaking from) simply caused by vibration chafing on the hose on the corner of the round thing!

The coolant also flows through the aluminium larger dia pipe, and if you take a look at the back of the engine (hard to see easily) there is a donut through which coolant also flows (uloop pic), the alloy loop can move and with vibration wear eventually leading to a hole in it (another place it could be leaking from). UV dye is another way to see where the leak might be coming from, but suggest you have a look here first as it could just be one of these places...

Hi Thsassos, the item that you are querying is the PCV valve.

[Clan]

Originally Posted by TurboDiesel2006

Thank you for all the comments.

I put everything back so I could re-start the car and get it hot. The car is currently on axle stands with its nose pointing in the air so I can get underneath. I started the car and when warm ran it at higher rpm to get it hot. I then inspected from the top and underneath.

1) the temperature gauge is fluctuating and the fan is on almost constantly so I guess I have missed re-connecting a connector somewhere.

2) the air-con condensate pipe is dripping a lot but I put that down to it being humid and the air-con is on.

2) When I crawl underneath I can that coolant is running along the underside of the EGR Cooler to the rear collar and then dripping off onto the mesh covered heater? hose. I can see coolant between the rear of the mesh and the hose.

3) I cannot see any signs of leaks from the two hoses on the top of the EGR Cooler.

4) I replaced the EGR Valve with a new unit about 15 months ago. I did fit a new gasket between the Valve and the cooler.

So is it likely that the EGR Cooler is the culprit. Do these fail and if so how? I thought the coolant went in one hose and out the other and it is sealed in that the gasket sealed the turbo exhaust gases not coolant.

The usual place for a radiator to leak is the lower corners , and after it has been left overnight under pressure as it cools ... small leaks are worse when cold , you may see signs of dampness which would be the leak as any rain water dries off as the radiator cools .

[TurboDiesel2006]

The radiator area is dry, cold and hot.

From underneath the car I can look up at the back of the engine and there is a trail of coolant running along the underneath of the EGR Cooler which then drips onto the mesh covered heater? hose.

I can see the EGR Cooler right angle inlet and outlet pipes from above and they appear dry where they are welded to the body.

Do EGR coolers fail (the car has done 160k miles) and if so how? It is a 2006 D5 manual with the 185bhp D5244/T4 engine.

[Clan]

Originally Posted by TurboDiesel2006

The radiator area is dry, cold and hot.

From underneath the car I can look up at the back of the engine and there is a trail of coolant running along the underneath of the EGR Cooler which then drips onto the mesh covered heater? hose.

I can see the EGR Cooler right angle inlet and outlet pipes from above and they appear dry where they are welded to the body.

Do EGR coolers fail (the car has done 160k miles) and if so how? It is a 2006 D5 manual with the 185bhp D5244/T4 engine.

that is good news that you have a leak , have you pressurised the system and actually see it running out or spraying from somewhere? You need to find the source before you dismantle anything really to make life easier , maybe you can look with one of those mirrors on a stick with the aid of a torch ....No EGR coolers are very robust i have never known one leak .

the mesh covered hose over the top of the gearbox is actually the bottom radiator hose ...

[TurboDiesel2006]

I have pressurised the system and there is a big leak in the right angled hose between the EGR Cooler and the cylinder head at the join into the cylinder head.

Access to the hose EGR connection is relatively easy but does anybody have any advice on how to access the hose clip at the other end. It is tucked away underneath a black Bosch component and shielded on all sides.

[TurboDiesel2006]

I removed the rubber elbow hose between the EGR Cooler and the cylinder head and found a small split by the hose clip. I have replaced this hose and (fingers crossed) the leak has stopped.

But when I started the car the cooling fan immediately came on full blast and stays on even when the engine is switched off. The temp gauge went to 1/4 reading and then dropped back to zero. It occasionally flicks up to vertical but drops back to zero after a few seconds. It stays at zero even though the coolant is at 89 degC. Vida tells me the error code is ECM-2000 Engine Coolant Temperature Sensor Signal to Low. Something in the back of my mind says if the MAF sensor is faulty it will give these symptoms. Any advice. Do I just fit a new temp sensor or should I check something else? Thanks