Rover K Series HGF - What actually causes it?
- Thread starter -westy-
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Caporegime
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Is it the stacks moving cause of the cheap plastic dowles used to locate and hold the stacks?
Associate
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i am not sure on this but something to do with the positioning of the thermosat in the engine. agw_01 knows what causes them im sure he will be along later to clear it up.
thedazman
thedazman
The biggest problem is that it has a very small coolant capacity, so the slightest leak tends to lead to overheating and gasket failure.
For want of a better description, the gasket is the weakest link, any problems and that'll be the first thing to go as a result in any coolant loss or overheating situation.
For want of a better description, the gasket is the weakest link, any problems and that'll be the first thing to go as a result in any coolant loss or overheating situation.
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Most HGF's aren't even caused by overheating actually Dolph. There is nothing wrong with the gasket itself.
There are several opinions floating around regarding HGF. The main one being the position of the thermostat.
When the thermostat opens, the cold water from the radiator rushes into the engine. This causes the head to contract which rubs against the sealant on the gasket, eventually causing the sealant to wear away. This isn't helped by the fact that plastic dowels are used. With metal dowels HGF is a lot less likely, as the dowels are stronger and stop the head contracting as far.
Another well known cause of HGF are air locks which then cause hot spots in the engine. Similar to the thermostat problem, where the rushing in of cold water creates cold-spots which then makes the head contract/expand causing failure of the gasket seals. Air locks can be caused by failure to bleed the system properly or a leaky waterpump or inlet manifold gasket.
A recent one I've heard (from penski) is that the liners in the engine drop, making a gap between the gasket. Hence why oil and coolant can mix etc. I can't say I've heard this one before, but I guess it's possible.
HGF isn't as big a problem as people say it is. Sure, the engine likes to eat them as much as I like eating pizza but it's shouldn't put people off owning the K series. I know people running original gaskets, and I know people who've had gaskets fail after 25,000 miles (mostly on new cars).
I think it's safe to say, that if the gasket has been changed properly, and the engine is regularly serviced, there's no reason that it shouldn't last 100,000 miles, or if it'll ever need doing again.
My 214 had it done about 15,000 miles ago so you should be fine for quite a bit westy
There are several opinions floating around regarding HGF. The main one being the position of the thermostat.
When the thermostat opens, the cold water from the radiator rushes into the engine. This causes the head to contract which rubs against the sealant on the gasket, eventually causing the sealant to wear away. This isn't helped by the fact that plastic dowels are used. With metal dowels HGF is a lot less likely, as the dowels are stronger and stop the head contracting as far.
Another well known cause of HGF are air locks which then cause hot spots in the engine. Similar to the thermostat problem, where the rushing in of cold water creates cold-spots which then makes the head contract/expand causing failure of the gasket seals. Air locks can be caused by failure to bleed the system properly or a leaky waterpump or inlet manifold gasket.
A recent one I've heard (from penski) is that the liners in the engine drop, making a gap between the gasket. Hence why oil and coolant can mix etc. I can't say I've heard this one before, but I guess it's possible.
HGF isn't as big a problem as people say it is. Sure, the engine likes to eat them as much as I like eating pizza but it's shouldn't put people off owning the K series. I know people running original gaskets, and I know people who've had gaskets fail after 25,000 miles (mostly on new cars).
I think it's safe to say, that if the gasket has been changed properly, and the engine is regularly serviced, there's no reason that it shouldn't last 100,000 miles, or if it'll ever need doing again.
My 214 had it done about 15,000 miles ago so you should be fine for quite a bit westy
The main reasons I've heard are poor servicing (incorrect filling/bleeding of the cooling system) and thrashing the hell out them from cold (were talking near redlining here) is the killer of these engines.
If the K series was such a dreadful engine, Rover would have never got awards for it, and countless manufacturers wouldn't have used it, these manufacturers include Caterham, Lotus and Ariel to name a few.
Let's also not forget that Landrover admitted servicing issues and abuse were to blame for a few odd isolated incidents of headgasket failure in 1.8 k series engines, well, they admitted it after the damage to the engine's reputation had been done anyway.
Also, not replacing stuck-open thermostats or removing them all together can introduce 'thermal shock', especially bad in alloy engines.
The K series does not have head gasket problems.
What it has in addition to the thermal shock issue is a requirement to check the liner protrusion from the block...Which most people don't do.
The liner seals at the base collapse which reduces the clamp load.
When you don't check this and fire it up and the head gasket goes you get an urban myth about them having dodgy head gaskets.
The head gasket going is the symptom of the liner drop not the problem in itself, which is why the same garages that don't check liner protrusion also don't solve the problem by skimming the head...Thus guarenteeing themselves future business.
Cheap, aftermarket head studs (pass through the entire block) may not have the correct tensile strength, leading to further liner-drop issues.
*n
If the K series was such a dreadful engine, Rover would have never got awards for it, and countless manufacturers wouldn't have used it, these manufacturers include Caterham, Lotus and Ariel to name a few.
Let's also not forget that Landrover admitted servicing issues and abuse were to blame for a few odd isolated incidents of headgasket failure in 1.8 k series engines, well, they admitted it after the damage to the engine's reputation had been done anyway.
Also, not replacing stuck-open thermostats or removing them all together can introduce 'thermal shock', especially bad in alloy engines.
The K series does not have head gasket problems.
What it has in addition to the thermal shock issue is a requirement to check the liner protrusion from the block...Which most people don't do.
The liner seals at the base collapse which reduces the clamp load.
When you don't check this and fire it up and the head gasket goes you get an urban myth about them having dodgy head gaskets.
The head gasket going is the symptom of the liner drop not the problem in itself, which is why the same garages that don't check liner protrusion also don't solve the problem by skimming the head...Thus guarenteeing themselves future business.
Cheap, aftermarket head studs (pass through the entire block) may not have the correct tensile strength, leading to further liner-drop issues.
*n
Caporegime
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That's all well and good, however every other manufacturer has managed to develop an engine without an appetite for Head Gaskets why rover can't or why they require so much maintenance is poor design.
Firestar_3x said:
The K doesn't have an appetite for HG's.
If a HG change is done properly, the engine will only probably need one or two replacement gaskets throughout its entire lifetime.
You try finding me a piston engine that won't need its HG changing at least once.
And the rotary engine needs its water seals replacing every 60k.