Oil leaks - Navigator

I am sure you realise it isn't normal. I would check carefully the studs on both sides. They shouldn't protrude more on one side than the other. Are some loose or stripped? It also sounds like the head gasket is leaking around the studs forcing oil up the tunnels and hence it is appearing around the nuts. Make sure the new gasket you are going to fit is a good fit, make sure the faces are undamaged and check to make sure the head isn't distorted and is properly flat. Then torque up the head nuts carefully and in sequence.

If the bike is running well, apart from leaking oil, you probably have not blown the head gasket. The oil is most likely to be seeping up the studs, from the crankcase. Since the studs on one side appear to be longer than on the other, a previous owner has probably screwed one side too deep into the crankcase. Unfortunately, this means you will have to remove the barrels to cure your problem. Measure the height of the correct studs, then, remove all the studs, and give the threads a good coat of locktight, or a similar sealant. Replace the studs, ensuring all rise the same height. Since this is, hopefully, not going to be done again for a long time, it would be worth checking the bores, and rings, before reassembly.

Don't forget - and this applies to all old British bikes and cars, especially the Rolls Silver Shadow - if there are no oil leaks visible at all, it's because there's no oil in it!

Previously keith_hammerton wrote:

Hi is it normal for oil to appear on top of the head nuts when eng is running. I am having a lot of problems trying to stop oil leaks on the right head and have oil coming out between fins and running down barrel. There are no leaks from rocker cover or banjo fittings but can see oil forming on head nuts. I have also noted that the left hand studs poke through the nuts but the right they are a good 1/8 inch below the top of the nuts and oil starts to pool in the hollow. Keith

Hi Keith,

Oil on the cylinder head can sometimes be traced to the rocker oilfeed pipe. The 'T' piece in the centre & the two banjo unions on the end are soldered into place. Solder is relatively soft & years of vibration takes its toll. Its a very simple test (have new 5/16" copper washers available).

Remove the oilfeed bolts (both sides) & catch the washers. Wiggle the pipe out to one side of the bike. Grip the unions - one in each hand - and try to twist one against the other. I'll bet you, that youcan feel movement there! Clean & resolder the joints (ask a plumber).

Use new washers on re-assembly. If none are available & your old ones look serviceable, copper washers can be made soft again by annealing them. I always thought this meant heating them to cherry red & quenching in water. I have read somewhere recently that cooling in air from cherry red has the same effect.

HTH...

Hi,

The only reason to quench is that copper at a temperature hot enough to blister your fingers is the same colour as cold copper. If you quench it then you know you are safe. It does not make any difference to the softening process.

Regards

Tony

Previously andy_sochanik wrote:

Previously keith_hammerton wrote:

Hi is it normal for oil to appear on top of the head nuts when eng is running. I am having a lot of problems trying to stop oil leaks on the right head and have oil coming out between fins and running down barrel. There are no leaks from rocker cover or banjo fittings but can see oil forming on head nuts. I have also noted that the left hand studs poke through the nuts but the right they are a good 1/8 inch below the top of the nuts and oil starts to pool in the hollow. Keith

Hi Keith,

Oil on the cylinder head can sometimes be traced to the rocker oilfeed pipe. The 'T' piece in the centre & the two banjo unions on the end are soldered into place. Solder is relatively soft & years of vibration takes its toll. Its a very simple test (have new 5/16" copper washers available).

Remove the oilfeed bolts (both sides) & catch the washers. Wiggle the pipe out to one side of the bike. Grip the unions - one in each hand - and try to twist one against the other. I'll bet you, that youcan feel movement there! Clean & resolder the joints (ask a plumber).

Use new washers on re-assembly. If none are available & your old ones look serviceable, copper washers can be made soft again by annealing them. I always thought this meant heating them to cherry red & quenching in water. I have read somewhere recently that cooling in air from cherry red has the same effect.

HTH...

Hi Keith,

Andy makes some good suggestions here but I would like to add one more. Check the flexible oil pipe to banjo feed connection. It is a small plain copper tube inside a flexible and very difficult to make secure with a hose clip. I chased oil leaks at the head gasket, rocker boxes and studs before, eventually,spotting that oil, under pressure,was being forced out of the banjo feed connection. Invisible under the tank, it sprays oil that blows backward under way, and dribbles between heads and out at front of barrel/head joint when parked.A eureka moment for me, and simple fix for all leaks.

Peter