Renault Grand Espace 2.2 dtI RTX - Glow Plug Replacement

[jag]

Hi and Happy New Year to all on this forum.
I think my glowplugs are playing up, because sometimes my car refuses to start, the engine turns over all fine but it just won't fire.This is more regular when the weather is extremely cold and first thing in the morning. The battery seems fine until you crank the engine many times to flatten it. But once my car has been started it's fine all day even if  leave it all day and try again later on, it's fine. Just the inital first start of the morning.
I have been informed that to prove it's my glow plugs i need to put an clamp meter around the cable to check that I am drawing about 80amps that s about 20amps per plug.
If I find that the reading is far less that 80 then I will probably replace all four plugs for best practice anyway.
But I wanted to know just how difficult is this job ?
I don't have massive hands so is that a good start   
Please any help will be most appreciated.

Regards Jags

[roy4matra]

... I have been informed that to prove it's my glow plugs i need to put an clamp meter around the cable to check that I am drawing about 80amps that s about 20amps per plug.

No, forget all that rubbish! :-)  All you need to do to check glow plugs, is measure their resistance.  Remove the connection to the glow plug, and connect an ohm meter between the plug terminal and earth.  If it is good, it will read between 0.7 and 1.0 ohms.  Usually those that have failed will either read a very high resistance (like mega ohms) or be open circuit.  i.e. you will get no reading.

If only one has failed, then you could simply replace that, but if you have more than one gone, and none have been changed in years, then it is probably time to replace the set.  Get a good fitting socket and take it nice and slow, and lubricate the thread, as you wind them out.  Don't over-tighten the new ones going in - they don't need much to seal and almost better loose than too tight.  If they are loose and you can hear gas leaking then you can nip them up a bit more, but if you over tighten them, you will probably never get them out again!

Roy