Necessary to remove the thermostat pipe when changing coolant?

[maxp]

When changing the coolant i know you have to remove the pipe from the L bend which holds the thermostat, and also the one above it.

Do you also have to remove the L bend bit along with the piping?

Im confused because i heard someone saying remove it, drop the thermostat out and replace the o-ring while your at it, but mr bentley doesnt mention it, just says take the two rubber pipes off and you're done.

[rubjonny]

you dont have to, but if you dont some coolant will remain in the block.  if you dont fancy the risk of snappin thermostat housing bolts, drain and flush what you can, then refill it with plain water.  run engine till thermostat opens then stop engine and when its cool drain and flush again. that'll shift most of the old coolant

[jamie_pyrite]

Yeah, be VERY careful with the bolts that hold the thermo housing on.. I rounded mine off, then cracked the water pump trying to get the remaing bolt thread out

[Gloves88]

Yeah, be VERY careful with the bolts that hold the thermo housing on.. I rounded mine off, then cracked the water pump trying to get the remaing bolt thread out

Can imagine how that must have felt!

I had to hammer off the housing to be able to get a grip on the rounded bolt. When i finally put it all together again one of the bolts snapped as i was tightening it!!!!!  I could have killed at that point lol

[jezza16v]

Yeah, be VERY careful with the bolts that hold the thermo housing on.. I rounded mine off, then cracked the water pump trying to get the remaing bolt thread out

Can imagine how that must have felt!

I had to hammer off the housing to be able to get a grip on the rounded bolt. When i finally put it all together again one of the bolts snapped as i was tightening it!!!!!  I could have killed at that point lol

Got the T shirt on that one! 

[maxp]

Ok i was in two minds before but i think ill be going with RJ's solution - two maybe three refils of water is nothing compared to bolt-sheared-funness