They are prone to rusting if not coated .
Depending on access on your trike it is easily replaced insitu .
Have a look at yours and see if it is bashed inwards rather than being flat { ish }
If it is still sticking out a little bit you might just be able to give it a
gentle bash in the middle and if lucky it might seal
To take the old one out there are a couple of old school methods .
Drain the coolant .
Make a wee hole in the centre then Bash a long very sturdy screwdriver through and lever off {
taking care not to score the sides by putting the screwdriver through too far }.
Make a wee hole in the centre then insert a large self tapper screw and grip it with pliers and bash the pliers outwards with the hammer
Most important part is making sure that the head casting where the plug sits into is
thoroughly clean and has no score in the metal leading from the inside to the outside .
On refitting , a TINY amount of Blue sealant can be used around the head lip if required or a Bars seal pellet put in the water .
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