Rear Crossover (Heater Manifold) failure mode?

[greiswig]

I really wonder if there is an incompatibility issue between the O-rings and the plastic. Mine were fine, but the way some of those failures look, it's as if the O-rings have leached the plasticizer out of the plastic and caused the failure of both the rubber and the plastic.

 

[timc930]

The front pipe where it enters the block was totally degraded. The only sealing was from the pressure of the upper pipe and the 2 securing bolts and the crusted coolant mix. The o rings had totally deformed and started to degrade with respects to their compressibility aka squishiness.

The rear manifold/crossover pipe was in a visually good state apart from the sealing o rings which were again degraded but not as much as the front pipe, oh and by the end there was a convincing smear of the red stuff to show it out up a fight.

The surprise item was the small capillary hose from the water pump. This was quite eroded, or batteries from the coolant pump job last done by Santa Monica Land Rover, who knows, but it’s replaced now so all good.

All this on a 2015 with 67k probably mostly city driving in la. So it’s been cooking for quite a time.

Yeah, I need mine to last one more week. 72K miles, mostly hwy.

 

[RoversFinest]

I really wonder if there is an incompatibility issue between the O-rings and the plastic. Mine were fine, but the way some of those failures look, it's as if the O-rings have leached the plasticizer out of the plastic and caused the failure of both the rubber and the plastic.

Yeah, I need mine to last one more week. 72K miles, mostly hwy.

Hey, hope you two are doing well. I'm trying to find the torque specs for the Heater Manifold. (LR109402) on my 2012 range rover sport. Hoping someone may have the specs saved somewhere, I am struggling to find it anywhere in the service manual on alldata

 

[Rover Range]

Torque: 9Nm