dInjectors is a bliksem to check unless you have the means to pressurize the fuel to the requires "bar" pressure. Bosch diesel electric will check them for you much easier. If you are going to attempt to remove the injectors, BE VERY CAREFUL of the spill rail ( its the thing with 6 rings connected by little metal tubes on the top of the injectors) as it can twist as you loosen the injector and then crack or break off..... VERY VERY FRUSTRATING !!
On the Glowplugs, they are very easy to replace, however again care must be taken when removing the old glowplug, especially if that glowplug has not worked well for a while. What happens is a carbon deposit builds up on the metal part that glows. On a new glowplug the whole tip glows a bright red/orange, which will generally burn off any stuff that is on the tip. as the glow plug deteriorates the tip doesn't heat up near the back and carbon deposits can build up there. So if you loosen the glow plug and feel resistance from just after you "crack" the seal, stop tighten up and loosen and repeat the process to try break off the carbon on the tip and not break off the tip of the glow plug..... YOU DON"T want that to happen !! I know on mine a few years back I battled with one or two of the glow plugs and just took my time repeatedly loosening and tightening, I think I sprayed some Q20 on the threads to seep in and assist getting the carbon of the tip.
Reinstalling the glow plugs is also easy, but again careful you dont twist that stupidly designed diesel spill rail
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