V70XC major engine oil leak

mpwdhc · Post by **mpwdhc** » 16 May 2018, 18:01

Hi there, new member here. After decades of 164, 240, 740, 940, and 850 ownership, I have ended up with a V70XC. It was purchased very cheaply with a raft of issues, but based on experience with the oldies, figured it'd be no huge deal. Many of the problems probably relate to poor workmanship previously.

One of the problems was a major engine oil leak from the front, drenching the timing belt. The belt was also showing signs of fraying along one edge, which turned out to be that someone, when replacing the belt, had fitted an overly long bolt to the crank damper, which started destroying the belt the second it was started. It also had CEL.

I removed the inlet manifold and breather, which was clear, including the channel down into the sump.

Cleaned everything up - oil seemed to be coming from the exhaust VVT area. This made sense as the leak seemed to me to occur when driven aggressively.

I locked the cams and replaced the belt, rollers, water pump (the blades of the impeller had been bent back and had gouged the housing), exhaust cam seal, and the VVT hub I removed from a car which was bone dry.

Drove it a short distance to the shops and home, including lots at high rpm to confirm the leak had been fixed. A few drips, which i figured might be residual. No CEL, improved power - the old belt must've been a tooth out or fitted without winding up the VVT. The next few trips were dry other than what was clearly a PAS leak from the res to pump hose, which I replaced. A dry short trip later, I was delighted enough to replace the oil soaked right mount, and took it for a 50km drive. Upon return it left a dinner plate sized pool of oil.

The back of the sprockets are not oil soaked, slipping a finger in behind the inlet sprocket comes out dry, so no leaks from the inlet seal. The water pump, tensioner, etc, is drenched.

I see discussions about the VVT seals, but the way I imagine it, if the big one leaks, it'd leak internal to the engine and be retained by the cam seal. I fitted the exhaust cam seal so the outer edge sits roughly half way into the bevelled edge

I can't see a crank seal leak drenching the water pump and tensioner - or could it?

Its hard to say, but it seems to be coming from behind the plastic cover between the cams.

Head gasket? There are no other symptoms of this at all. The leak seems prevalent after a longer run rather than a short hard run, which to my mind discounts the VVT hub. I readied myself to deal with belts, mounts, coil packs, flakey instruments, shocks, but a head gasket is a step too far.

Any ideas appreciated.

Post by **SuperHerman** » 16 May 2018, 21:50

What year and engine are we discussing? Is it dual VVT? It helps me when I pull up pictures.

Per your description of the repairs you performed you would have had a good look at the head gasket area. What did you see? Gravity tells us oil flows down. The only variable is if wind pushes the oil around. Are you running the car with the engine oil pan on?

Based on your repairs and descriptions I would say the head gasket or a crack in the head and the block are the only real possibilities unless you have a leaking cam seal which you replaced and say are dry. The VVT leak would be obvious. You sure it is not the oil pump or the power steering?

I suggest you add some dye to the oil and before you run the car clean all the residual oil up really well. The dye will glow with a black-light and locating the source should be easy. As any old oil will not have any dye only new areas will glow. Let it idle for sometime and see if you see anything - slowly stretch out your driving and checking until you can narrow the area. After you have done this and you still see oil, look closer at the power steering as you didn't add dye to it.

mpwdhc · Post by **mpwdhc** » 17 May 2018, 17:25

Thanks Herman,

It is a 2001 with VVT on exhaust only.

There is a plastic cover hiding the head to block face, but the oil does seem to be coming down from that area, saturating the tensioner and water pump. I suppose I could remove the belt and get the cover out, but the difficulty is that it only seems to leak after a lengthy run. It is definitely engine oil.

It is frustrating as until the leak is fixed, its not worth doing anything further with the car.

At idle, a plastic bag on the oil filler doesn't exactly get sucked in, but there is no positive pressure, either. Perhaps might be worth trying such a test when it starts to leak. Very frustrating. I spoke to a Volvo mechanic friend who is stumped, and says he has never seen a head gasket oil leak, and yet at this point it seems the most likely scenario.

Post by **SuperHerman** » 17 May 2018, 20:34

I cannot find any good unobstructed photos of the block and head from Cylinder 1 side. What I was hoping to find was a view showing whether the head has an oil clean out galley plug that could be leaking if not tight enough or without sealant. I see freeze plugs, but assume these are both for coolant, but maybe not. The other possibility is one bolt holes milled into the head goes through to oil or is now. Maybe ask your Volvo friend.

I still think you should put some dye in there. I have used it twice - once with coolant and once with oil - both times finding the leak was easy.

mpwdhc · Post by **mpwdhc** » 17 May 2018, 21:39

Head gasget overheat problem identification

I presume that gallery at the left lower corner of the pic is the oil supply to the cam gear, but I wouldn't expect a leak there to show over at the water pump.

Gallery plug is an interesting thought.

Post by **SuperHerman** » 17 May 2018, 23:39

Agree with your conclusions unless the head gasket is bad. On Subarus head gasket oil leaks are very common, but not typical in Volvos. Along this line, maybe your cylinder head bolts have loosened up or were installed incorrectly. This problem was common on certain years of the Land Rover Discovery. Do you see any signs the head gasket was changed? If so this opens up many possibilities as to why - one big possibility is coolant was left in the block holes for the head bolts and as the car heats up the gas pressure causes movement. Or more likely the engine was overheated, and the head is warped but only oil is leaking. Along this line - maybe the head gasket was changed and the head was not milled.

Other common leaks are the oil pump/front crank seal, turbo lines, oil cooler and maybe the dipstick tube -- but these are not where you state the leak is coming from.

Looking at the photos in the link you provided, it appears there is not galley plug but it is hard to tell.

Basically, unless the oil is getting blown there, you have the VVT Solenoid gasket, VVT hub, upper cam cover, cam seals, head gasket or a damaged head/block.

Most of these you can and have visually or physically excluded.

How many miles on the V70XC? When you did your original work how was the oil build up? Did it look like it was there for a long time with parts baked on or was it pretty fresh? The parts you replaced - how old did they look? Any signs of new coolant hoses? Maybe it overheated and a prior owner did a miserable head gasket repair.

It is clear from your description of the prior work the car saw some shoddy repair work. You will have to dig and see how much at what work was performed. At this point the only thing known is it is not suppose to be leaking and it is.

ashgoldS60 · Post by **ashgoldS60** » 20 May 2018, 13:39

I have been chasing a similar leak on a 2001 S60 NA engine. I thought head gasket was a possibility but the feedback I have had says unlikely. There is an oil supply to cool pistons and you can see the part which controls flow in a parts diagram. It threads in and has a gasket and is located in the timing belt area to the right of the water pump. Other than cam seals which you have looked at, there is a plug for turbo oil supply which is not used on NA engines. Supposed to be on side near firewall and up high. I have had a hard time locating where this plug is. It threads in and also has a gasket. I'l be curious to see if you find your source

mpwdhc · Post by **mpwdhc** » 29 May 2018, 17:21

Hi guys,

Thanks for the thoughts. Just thought I'd give a bit of an update. I removed all the timing belt stuff and was able to (just) wriggle out the belt cover backing. It looks pretty clean on the top half, which seems to discount any leaks from the top half. The area around the oil pump looks grubby but not sopping wet. Nonetheless it is the only real lead at this point so I have ordered an oil pump seal kit.

The firewall side of the engine, where the turbo cooler line is, is nice clean alloy, so unless the cooler line banjo has some freak pinhole leak which shoots in directly to the belt area, we can discount that - but hey, anything is possible with this thing.

Ashgold, I can see the plug you mean, and it feels tight. I imagine it has a copper sealing washer so have left it at that.

In answer to Herman, it appears to be untouched and original - no sign of head being off, hoses replaced, etc. There is a receipt for a radiator a number of years ago. I suspect the car developed the leak, someone did the belt and cam seals, messed up the belt install and it still leaked anyway, so passed it on to the guy I got it from. I can tell the seals have been done as there is some scratching on the lip of the head, and as mentioned earlier the belt was chewed up from someone installing an overly long bolt on the damper. The idlers looked pretty good. The pump was volvo and looked fresh, but the impeller vanes had been bent back and had gouged the pump body. The car always had CEL, and it was very hard to start when left to sit longer than overnight - I bought a non return valve for it, but never ended up fitting it, and after the belt was in and timed correctly, all CEL and starting issues went away. It is no wonder it seemed so thirsty, too. I haven't really been able to ascertain economy post belt change as its only had a short trip.

The car is showing 130,000km but I don't know if in the event of swapping instruments, the mileage shown is from the car or the cluster?

Post by **jonesg** » 29 May 2018, 18:43

mpwdhc wrote: 29 May 2018, 17:21 Hi guys,

Thanks for the thoughts. Just thought I'd give a bit of an update. I removed all the timing belt stuff and was able to (just) wriggle out the belt cover backing. It looks pretty clean on the top half, which seems to discount any leaks from the top half. The area around the oil pump looks grubby but not sopping wet. Nonetheless it is the only real lead at this point so I have ordered an oil pump seal kit.

The firewall side of the engine, where the turbo cooler line is, is nice clean alloy, so unless the cooler line banjo has some freak pinhole leak which shoots in directly to the belt area, we can discount that - but hey, anything is possible with this thing.

Ashgold, I can see the plug you mean, and it feels tight. I imagine it has a copper sealing washer so have left it at that.

In answer to Herman, it appears to be untouched and original - no sign of head being off, hoses replaced, etc. There is a receipt for a radiator a number of years ago. I suspect the car developed the leak, someone did the belt and cam seals, messed up the belt install and it still leaked anyway, so passed it on to the guy I got it from. I can tell the seals have been done as there is some scratching on the lip of the head, and as mentioned earlier the belt was chewed up from someone installing an overly long bolt on the damper. The idlers looked pretty good. The pump was volvo and looked fresh, but the impeller vanes had been bent back and had gouged the pump body. The car always had CEL, and it was very hard to start when left to sit longer than overnight - I bought a non return valve for it, but never ended up fitting it, and after the belt was in and timed correctly, all CEL and starting issues went away. It is no wonder it seemed so thirsty, too. I haven't really been able to ascertain economy post belt change as its only had a short trip.

The car is showing 130,000km but I don't know if in the event of swapping instruments, the mileage shown is from the car or the cluster?

There's nothing the water pump vanes can touch when the body is bolted to the block. Can't happen.
I would suspect the wrong pump was installed.
The bolts pass through galleys and new bolts have sealant on the threads, I don't know if the galleys are all coolant or maybe there's an oil passage too.

What if you clean the block up, leave the plastic backplate off and watch it for oil, leave the dust cover off the belt area.

Bolts that are too long can cause block damage. What were they thinking.

mpwdhc · Post by **mpwdhc** » 31 May 2018, 03:57

Someone needs to throw their tools into a lake. They would've known they'd damaged the seal upon installation, and it more or less fell out anyway. Resealed the pump today, I'm feeling confident !