Talk Morgan Forums Morgan Sports Cars Maintenance & Servicing Plastic Radiator Drain

So, I have learnt my lesson. With the 2011 +4 Mog now 10 years old, and plastic rad still going strong, time for coolant change. Though my preference is always to pull off the bottom hose, it was a bit tight to get to and I thought I might run the risk of fracturing the stub. So, the drain plug looked so easy! Out it came with no issues but putting it back in, it snapped with very little effort. leaving the threaded portion inside.
I managed to retrieve the broken bit and could see that it fractured where the end of the threads meet the smooth bit. Poor design...it is made hollow for half its length!
So, time to bite the bullet, which maybe I should have done years ago and a nice new shiny ali one will soon be on its way from Si-Fab.
Added note: I have just canned the old coolant and it’s only about 5 litres. The handbook says the capacity is 10 litres. So does the block need draining separately! I can see a square shanked plug down on the offside of the engine just forward of the engine mount and about an inch or so above the sump interface. Would that be it,? or is the capacity in the book a mis-print?

Just found this for you might answer your question http://www.talkmorgan.com/ubbthreads.php/topics/522831/Recommended_anti_freeze_streng

Many thanks for that but I am happy with the mix and type that I intend to put in. My concern really is do I need to drain the block and if so, how?
Although I drained under cold conditions i.e. stat probably closed, after the initial gush, it went on running slowly for quite some time, which I assume is the head draining via the tiny bleed hole that is usually incorporated in stat.
Temptation of course is to simply refill with a 50/50 mix but of course there is still some old stuff in there somewhere.
I ask myself....Does it really matter...I wonder what garages do?

Three Duratec rad swaps and I have to confess to never draining the block although I do keep my coolant in reasonable shape.

However there is always about a half a cup of coolant left in the pump cavity even after the bottom hose has been removed. That coolant will drain out if the stat is removed and usually runs into the alternator if you are not ready for it

Thanks Roger. Without a block drain, it seems that the system would need to be refilled with clean deionised water, run to get it mixed and then flushed out, and repeat several times to get rid of all the old stuff before adding 5 litres of antifreeze concentrate and topping up with water.
I have concluded that if I just refill with 50/50 on top of what is left in there, I won’t be alone in the world by adopting that approach. As I bought a 5 litre can of antifreeze, I guess once the new rad is fitted and engine run, I could drain down just once and refill with 50/50 and so use up what I have purchased.

New Si-fab radiator now installed and flushed and refilled with 50/50 mix of Ford Super Plus.Took me about 3 hours. Quite a tight squeeze getting it down past the steering bellows even with track rods swung out of the way. If doing again, I would try to separate the fan assembly from the rad first. Once out, I could see a couple of small allen bolts on top, which when removed, allowed the fan assembly to be split away by a slight pull upwards.
The rad itself oozes quality workmanship and came with all the necessary bits well packed.