This page is under construction as of May 2021, thus it is incomplete, please come back to learn the full story in a bit.
Years of doing Rover K heads, seeing the damage caused by overheating of the alloy, often even with people taking care, looking after their pride & joy. Then there are the multiple tens of thousands totally trashed, especially sport model cars.
So what did I gleen from looking at the dismantled engines, listening to others investigations and the ideas on faults/fixes, and even the bull spouted by so called experts & now embedded upon the net that people think its true. Like the 'elastomer' seal is to blame, the plastic blok dowels are to blame, the long bolts that hold the head on are to blame and various other 'things'.
I will put forward what I understand & can see, you think it over & decide if it makes sense & I hope benefit from the knowledge.
Firstly as I was told by a Rover tech engineer, as the engine was being designed in the 80's rover was looking to the future & wanting to show off it could produce an efficient & emisions friendly unit unlike all the carburated & somewhat inefficient vehicles populating the roads of the world at the time.
With this in mind the cooling system is built to RAPIDLY heat up & come off Choke/enrichment for the lady in her metro doing 1 or 2 miles or less to the shops as so many trips we make are like. Thus it consumes less fuel making it fuel efficient getting off enrichment, and secondly cleaner emisions, win win.
So this is great until you put it in a sportier model vehicle or 4 by 4 type where the owners are used to just jumping in, turning key and driving off at speed without allowing a warmup & the stat to begin working. So the 'rapid warmup' now turns into 'Rapid fryup', the owners have just ruined their cylinderheads & the nightmare of repeated fails begins- aided by another fault of the design, the headgaskets 'firering'.
So i shall go into my thoughts, backed up with pictures that should help you 'see'. The trouble is where to start- i'll go with flow in the cold engine. The stat is closed, to open it we need heated coolant flowing over the wax portion, this comes via a takeoff from the water outlet branch on back of head- exh side cyl 4. A pipe assembly takes the coolant to the plastic stat housing under the inlet manifold at front of engine.
The pipes one sees are fairly large Diameter, so one might think there is decent flow.
So we begin to see an engine with 4 cylinders on fast idle around 1000rpm with searing combustion gases at around 420C/788F heating the chamber, flowing around/heating the exh valves/seats & they passing their heat to the head alloy, finally the gases heating the head alloy while passing through the exh ports to be expelled into the exh manifold. This heat is dealt with by engine coolant in the water jacket in contact with the head alloy & absorbing it, the coolant passing through the stat housing has just enough flow through the engine to move the warming coolant so more cold coolant can absorb more heat & thus keep the alloy at stable levels.
So here we have the elastomer original headgasket design, quality made Stainless steel/inox core which removes all the known possibilities of giving trouble & failing from chemical attack or rusting away as many other gaskets do!!!!
rover got may aspects of the engine spot on, and this simple stainless core one of those perfect aspects.
Sorry, I am finally upgrading my site starting May 2021, this page is a new addition & is yet to be filled, come back in a while & hopefully its completed