Rover 25: Oil, Water and a Head Gasket

Hi all

Simply: the old beastie's temp guage hit red, 1 mile from home. I limped her back, coasting down a large hill to get the temp down a bit. I left it for an hour to cool down (me, not the car, I craped my self!!!) and then I had a look at the engine bay, there was watery, rusty looking oil all over the rear , right hand side of the engine bay.

I looks like it has dumped its oil out of the coolant filler tank!!! By the look of the oil spread, it looks like oil and water mixed somewhere, the engine over heated and forced the mixture out of the coolant filler cap all over that part of the engine bay.

Assuming that the head gasket has blown and hoping that the head is not warped ( I tried to keep it as cool as posible, honest guv), I started taking the head area apart. Once the cam covers were off I could see the cams.

Now, I was expecting to see the same kinda gunk all over the cams that I have all over my engine bay. But, no. The cams look relativly perfect. The oil is clean and pretty nice. It all looks as it should be.

So, before I forge ahead removing the head, could there be another reason, other then the head gasket, for the oil and water mix coming out of the coolant filler cap? I dont understand how the crappy oil an water mix is not on the cams, but it is in the coolant system. Surely after a mile or so, the water and oil mix would be everywhere in the engine and coolant system.

So, can anyone throw any light on this before I get cracking on the head?

Cheers AC

Reply to
AC
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If the engine has an oil-water oil cooler then a rupture in that can cause water/oil to fix.

Reply to
Sandy Nuts

Sound good, I check for that. But, wouldnt the oil water mix end up in the head and on the cams?

AC

Reply to
AC

Depends where the oil cooler is (and if indeed there is one and it's coolant cooled). Usually you'll find two coolant pipes connecting to the oil filter mounting bracket.

There might not be any water in the oil, but there maybe oil in the coolant. Unlikely, but possible as oil pressure will be greater than coolant pressure.

To be honest, though, my money is on the head gasket. The K-Series engines are notorious for killing them and this sounds about right.

Depending on the nature of the blow, the water could simply be getting burnt and exiting via the exhaust, and any little water in the oil is evaporating.

Reply to
Sandy Nuts

Not necessarily, as oil in a cooler would be under positive pressure. Greater than the pressure in the cooling system. Unlike a HG failure, where pistons can suck water in, as well as blow oil out, especially if it has blown in the vicinity of the oil feed to the head. Mike.

Reply to
Mike G

Just had a peek in the Rover service manual, and the oil doesn't look like it is water cooled.

Reply to
Andy

What year is your car?

Sounds to me like the nylon dowel that also acts as the oil-way to the head has gone, along with the gasket around that area. This would pass pressurised oil into the water, but clean oil would also continue to the head (assuming that there was any oil pressure left), hence the clean cams.

Andy.

Reply to
Andy

In news:f33oro$chr$1$ snipped-for-privacy@news.demon.co.uk, Andy wittered on forthwith;

eh?

Reply to
Pete M

In news:D2c5i.4756$F snipped-for-privacy@newsfe4-gui.ntli.net, AC wittered on forthwith;

The head gasket has gone. It's a K-series Rover. The chances of it being something else are very minimal indeed, microscopic. Smaller than a truckers brain.

Reply to
Pete M

"Pete M" wrote in message news:f33qlv$q83$ snipped-for-privacy@registered.motzarella.org...

Agreed. They are very reliable cars - then the head gasket goes.........

Reply to
gazzafield

If it's the head gasket it depends what blows, the oils at a higher pressure than the water if it's the feed to the cams that blows.

Reply to
Duncan Wood

Thanks for all the replies. Much appreciated.

Head gasket it is then......... thats gonna be fun.

AC

Reply to
AC

When you've got the head off - DO NOT rotate the crank. You may disturb the liners.

Reply to
Sandy Nuts

I've just finished doing the head on a Rover 25 (yesterday!), so if you'd like a list of tools before you start or any help let me know.

When you get the head off, look at the gasket that surrounds the left hand (as you look at the engine) dowel - you should find the damage there.

Andy.

Reply to
Andy

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