Head gasket gone

[racing green rover]

Hi after having a viton inlet manifold gasket put on the car has not been using as much water and not misfiring from cold but it's still losing a slight bit of water however when I checked the oil there is like thick toffee yoghurt substance around the filler cap and on the rocker cover gasket and around the inside edges of the rocker cover
But the oil is black on the dipstick?
It's a 1.8 turbo many thanks

[suzublu]

Must be the time of year mine's just gone too

[roverbarmy]

Originally Posted by racing green rover

Hi after having a viton inlet manifold gasket put on the car has not been using as much water and not misfiring from cold but it's still losing a slight bit of water however when I checked the oil there is like thick toffee yoghurt substance around the filler cap and on the rocker cover gasket and around the inside edges of the rocker cover
But the oil is black on the dipstick?
It's a 1.8 turbo many thanks

There can be water/coolant residue around for a while. In winter, there can be condensation in the rocker cover. Air locks take a while to clear, so coolant will need small top ups. Clean everything, refresh the oil and see how it goes before assuming HGF.

[racing green rover]

Thanks will see how it goes on I think it's got the MLS gasket on as I can feel the tab protruding under the exhaust manifold on the gearbox side of the engine

[T-Cut]

Originally Posted by racing green rover

But the oil is black on the dipstick?

You don't necessarily get the classic mayo appearance in the sump oil if the coolant leakage is small but continuous. Under these conditions, the glycol gets incorporated into the oil while most of the water is vented off from the hot mixture. This is typically evidenced by steaming from the filler cap and a heavy creamy gloop in the rocket cover. The oil develops a very black, viscous consistency that's hard to appreciate until it's drained off. You have to keep a very close eye on a 1.8T with slow, unexplained coolant loss.

TC

[racing green rover]

The oil is like a golden colour when I wipe it off dipstick
Many thanks

[Lovel]

Originally Posted by racing green rover

The oil is like a golden colour when I wipe it off dipstick
Many thanks

Water is heavier than oil and sits in the base sump unseen until it reaches the level of the suction for the oil pump, and then it starts to mix and play havoc. Oil level in the sump may increase over time if you keep observing it.

When I think of all the Kseries engines I have had over the years and which operate in a relatively cold climate up North, I have very rarely seen any mayo on the inside of the rocker cover oil cap. It sounds like you have copius amounts so further investigation will be required. For a hands on guy The head gasket is a relatively easy job and with the correct approach you can do a good job in some 4-6 hours with very little costs. After inspecting the liner heights relative to the block , pistons and liners closely. If you go down the route of the head gasket, change it to an elastomer version from Payen BW750. One further thing to add is if you have mayo circulating around the oil system the turbo charger will not take too kindly too it and may fail sooner rather than later.

[racing green rover]

Don't the elastomer gaskets suffer from the elastomer coming off the gasket over time though I was looking at the n series gasket with the stronger oil rail will that be ok being fitted
Many thanks

[Lovel]

Originally Posted by racing green rover

Don't the elastomer gaskets suffer from the elastomer coming off the gasket over time though I was looking at the n series gasket with the stronger oil rail will that be ok being fitted
Many thanks

Yes they do fail, but they are more tolerant than an MLS to imperfections and if fitted to a reasonably flat cylinder block and head then they will survive somewhere between 5-10 years again before the mayo cycle begins again. Treat them as a service item ! The elastomer bond is lost on the steel gasket and eventually shimmies out after the many hot and cold pressure cycles over the years from the coolant being at 15psi or so, eventually coolant passes into the oilway. The BW750 elastomer bead has been reinforced somewhat over the years, however MGR did fit these in production too. The stronger oil rail is a waste of money IMO.

The latest nseries gasket will require factory specification tolerances for it to survive long term. I would suggest if your cylinder block or head are just the slightest out of spec then a MLS or Nseries MLS is not for you. The nseries uses through bolts of higher tensile rating and therefore requires less turns overall to achieve a decent clamping force. The nseries gasket is designed for use with an alloy block and head that has been pressure casted? which has less tendency compress as much as MGR spec alloy which was gravity cast.

[75c]

Originally Posted by suzublu

Must be the time of year mine's just gone too

It's been my worst nightmare since I got mine. I'm so worried about it. Sorry it's happened to you both !