Talk Morgan Forums Morgan Sports Cars Maintenance & Servicing Valley gasket 97 +8

Car in for its service and brakes need a lot of work rear brakes none existent and while it was in that noted the valley gasket is deteriorating, how hard a job is it to tackle or is it best left to the garage ? It’s probably original and the cars done 40k

It's not so bad a job. The coolant runs through the front so you also need to lower the level. Once the bolts are out and the inlet manifold is off, two brackets secure the gasket, one each end.

When lifted you get a good view of the camshaft and followers.

I used some sealant around the water jacket, and it went back on and was OK.

Just a bit fiddly with the fuel supply, coolant, and so on.

As Dave suggests this is not a desperate job , but you will need to work very methodically and it will take some time.

I would first remove the bonnets entirely to give you good access, and lay plenty of protection over the wings.

Then start taking photos , lots of them, to show you what it should look like.

Then ensure that you have a clean surface to accept all the parts as they are removed.

Now label everything very carefully as you remove it , and ensure that you mark the correct orientation.

Once everything is removed you will probably have a lot of cleaning to do because if the gasket has deteriorated then the chances are there will be some corrosion on the heads, and there will also be a lot of old sealant around the edges of the gasket. If you want to avoid getting any of the dirt etc into the engine it is important to protect the camshaft/lifters area with a good mask, and the same for the intake ports in the head.

This official Land Rover video goes through a lot of the EFI engine and its parts and may be worth a look if you are unfamiliar with some of these BUT what it lacks in brevity it more than compensates with length , so be warned.

https://www.youtube.com/watch?v=yLYwG_QSW4w

Good luck

Do you have to remove the valve covers to remove the intake in order to replace the valley gasket?
It would be really helpful if you could list the order of disassembly of the parts.

Thank you.

Cannot see why you would have to.

Can’t say for certain with EFi as I’ve not done one but all the carbed V8s I’ve done the rocker covers need to come off the remove the inlet manifold.


Use a composite valley gasket with a very light smear of welseal. Getting all the bolts back in takes care, it’s very easy to get them crossed.

At 40k you may want to consider a cam swap (the cam wears very rapidly on these engines) and you’re halfway there. Inspect it anyway and decide. The engine will respond very well to a slightly hotter cam and new followers. But you will have to shim the pedestals to set the preload.

You should be able to do all the above for about £500 in parts. It’ll take a couple of working days and reward you with about 20bhp more than standard and compensate for the lost 20-30bhp for a worn camshaft. So a real works gain of around 50bhp.

Not sure what you mean by deteriorating? These gaskets are essentially a sheet of steel with gasket material either side . If it isn’t leaking don’t change it! Because of its location there is a natural tendency for all sorts of debris to gather there , if this is the case simply make a modified end for your Henry hoover .

The job itself is fairly straightforward - there are two things to need to ensure you do .
1) when you drain the coolant , ensure you remove the two block drain plugs under each bank of exhaust manifolds.
2) Take great care when you remove the inlet manifold that the valley gasket isn’t disturbed at the cylinder heads , then when you come to remove the gasket that no debris from it falls into the engine.

Good luck

It takes me back.......I needed to change the hydraulic lifters on my engine. It was over 90k miles, and ran pretty well, as I thought. When I lifted the valley gasket, I faced the usual black tar. It was as if someone had poured a few litres of quick setting tar over everything. I did change the lifters, but was never happy that it was impossible to clean that tar off. I also found that some of the cam lobes were almost gone, especially the rear one, which effectively had no cam remaining.

A year later that engine came out and was replaced. The tar, even inside the front cover, came off in chunks like toffee.