Quote:
Originally Posted by RodgerD
I've got two 1.8 turbo with HG problems and still to decide which gasket to use. I'm going down the route of sourcing 1.4 blocks as they shouldn't have been stressed like a 1.8T engine. I'm going to make sure liner protrusion is 0.005" and siding with the elastomer gasket, possibly with blue Hylomar. Going to look at torque settings, going to test an old oil rail to decide what torque the ladder threads will take and make a judgement.
I'm also looking at keeping the coolant as close to the thermostat temperature as possible and not rise to 100+ degrees before the fan kicks in. By the time the fan cuts in head temperatures will be well above 100 degrees C. Higher coolant temperatures compared with ambient temperatures means the coolant system is less efficient at dissipating the heat around the head, so every degree nearer thermostat opening temperatures means the cooling system is more efficient. Given the low level of coolant in the system, a close control of coolant temperature at around thermostat temperature should help with the head softening.
I'm also looking at under bonnet temperatures, as this will play a part as some of the heat dissipation is from the head external surface with the under bonnet enclosure creates a heat trap. One possible way of reducing under bonnet temperatures is to remove the centre section of the double bulkhead and allowing a heat flow route out through the driver's side scuttle vent, or modifying the centre section with extra vents. It might even be worth looking at installing fans where the bulkhead panel is now to give positive under bonnet ventilation.
If the k series HG issue is going to be solved, it requires looking at not just the engine with the problem of expansion of dissimilar metals, but its installation as well.
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Hi
1.4 blocks can be used but why the block should not be annealed it sits in a bath of coolant and will not suffer the same problem as a head if your engines came from the factory with low liners just fit shims to the liners
Elastomer gaskets will be fine but I am unsure of the blue Hylomar as I don't recall anyone who has used it in conjunction but it is good stuff so I understand your reasoning
Rover spent huge sums of money developing the metallurgy and design of the head bolt it allows the crank stresses to be dealt with by the sandwich taking the torque settings beyond 64nm will not apply any additional clamping force and changing the bolts to higher tensile ones and trying to apply more clamping force will stress the crankshaft
I certainly do agree with you on the fan should cut in much nearer the stat opening temperatures and I am looking to fit an aftermarket fan to the inboard side of the radiator set to operate at a more realistic temp, this will give you a backup fan if the aftermarket inboard fan dies and can be retro fitted to the nasp without any problems and without touching the existing, but unsure of the turbo as to space available. This will not be done until after the two experiments I am trialing have concluded
Significant annealing does not occur below 250'c which will not occur unless you loose coolant and continue to run the engine I would spend my money and time on making sure the cooling system is in peak condition and treat the parts like service items and replace on a regular basis, also open up the head casting flashing in the water ways to achieve a full unhindered flow I would also ditch the oat antifreeze
Improvements in engine bay airflow are a waste of time imho unless you are racing the car
In view of the low cost and ease of head gasket replacement I would recommend replacement at say 50k along with the timing belt and water pump as part of the service interval
I give you the above as advice and not criticism if you are going to try these things then fair play to you it's trial and error and experiments that enable us to keep the marquee going
Good luck
Doc