Series 3 Yet another problem

Ok so the two and a daughter five bearing diesel in mi liddle tank is acting up.
I let it overheat a tad over the weekend by accident to about 110 Celsius. The water boiled, raised the pressure and blew the top off the expansion bottle. When I blew through the vent pipe it was blocked.
Now I don't consider it fried at this temp but I'm having trouble starting the sodding thing.
It does start and runs as normal but it takes about twenty seconds turning over before it fires into life. As if no heater plugs are working.
What deya recon???

Sounds like the glow plug's or something associated.

Test the glow plugs. If one goes then none of them work.

I think they are the upgrade ones with the cable running from one to the other. Worryingly the cables are red. I think the britpart ones are red.
I suppose I could have been running on say two since I stole it and another one has gone. I used about 80% of the battery this morning to fire it up and with only a mile or two to work I stopped at the shop for a tin of easy start before attempting the homeward trip. The light still comes on nice and dimly when I turn the key.
I'll pop out now and pull em out for a looksee.

Well I only needed to have a butchers at the front one.
It has a hole in the end

Better get a set ordered.