I live in Georgia and have a 2000 xk8 and my conv. top hydraulic lines were replaced 4 years ago and are working fine. In the trunk at the pump the outer surface of one of the hoses is beginning to be brittle and flack off. The mesh layer is perfect and the hose remains flexible but I fear the extreme heat built up in the pump area between the outer fender and the interior trunk liner is not helping my hoses at all.

Is there something I can wrap my hydraulic hoses with that will help reflect some of the heat away from the hoses themselves?

bcucharternet

 

You should not have a problem getting some foam insulation in there, but I wonder if the fluid is heated by the pump, which would render the insulation useless? Easy enough to check the line after operating the top.

When I replaced the hoses on a 2000 XKR a couple of years ago I found that the outer covering had flaked off all the hoses, including behind the back seat which is not exposed to solar heat.

Were the hoses replaced by the dealer or another source?

 

The dealer replaced the hoses.

 

That means they may have used the same hoses that failed. Can you read the printing on the hoses? I wonder if the one that's flaking is different, but I expect you can't get any information from that hose.

 

I think you are right to be focusing on the heat issue. A few considerations:

- insulating the hoses couldn't hurt, but even with that in place the hoses will still reach the temperature of their surroundings over a period of hours. It might be of most help for periods where you're parked in the sun for something less than all day.

- Another idea would be measuring the temperature at the pump and comparing it to that inside the trunk. If it stays cooler inside the trunk (I doubt it) you could leave an opening between them to bleed heat from the pump area.

- the pump, being what's called a positive-displacement type, won't directly heat the fluid much if at all. But the pump motor and especially the solenoids do get hot, especially with repeated operations.

Hope I'm wrong about this but when the jaguar-supplied hoses start to look like what you described, they are probably headed downhill.

Have you inspected the hoses at the latch end? Things get even hotter there.

Good luck.

 

The hoses at the latch end are fine with no signs of any problems including at the fittings.

bcucharternet

 

It is really common for these hoses to deteriorate in the heat, although four years seems quick. I'll bet they were sitting on the shelf for a few years also.

My experience has been, even with the outer shell delaminating, you still may have a few years of service life for other that the top latch hoses, which are under the most physical stress.

When it unfortunately becomes replacement time again, there are several aftermarket alternatives now that would be a better choice than the OEM hoses.

 

I installed Gus's LSI pressure relief valve JagRepair.com - Jaguar Repair Information Resource last year. The valve reduces the up/down and latch peak pressures from 1600psi to 950psi.

bcucharternet