fanbelted

I've got 235K miles on my evo 9, and although it has had coolant flushes done before, as far as I know the engine block coolant drain has never been opened. I would like to do a COMPLETE coolant drain, because I've heard that scale, crud, and sludge will accumulate in the block if the block drain is never opened. Does anyone know where the block drain plug is, and how many there are? I am not talking about the drain petcock on the radiator, but the block drain plug(s) that are supposed to be located on the engine block.

RallySport9

iTrader: (20)

Having thoroughly looked over the evo 8/9 4g63 on an engine stand there doesn't appear to be a coolant drain plug on the engine block. I remember having to flush it put by rotating the block upside down in different directions to get it all out. There can never be a block drain on any engine due to too many angles coolant sits. Just try disconnecting the lower rad hose and sucking it out with a shop vac? Lol

fanbelted

man, are you 100% sure? That would be such a bummer if there is no block drain on the 4G63 😟. Other cars do have them, like this guy who is talking about his Mustang. He kinda wanders around a bit before getting to talking about the block drain at time 1:55

RallySport9

iTrader: (20)

Thats the thing I'm not 100 percent sure. That's just my experience looking all over for one on an 8 and 9 engine on a stand..it would be nice I'm hoping another member who may have found one can prove me wrong.

deylag

iTrader: (23)

No, the 4g63 doesnt have a block drain coolant plug. The best way to remove coolant sludge is by doing distilled water flushing. I am sure there is a machine that can cycle the coolant/water through the engine while its running to clear out all the rust. See coolant flushing for 4g63s. Do not try to assume that a JDM 4 cylinder turbo motor has the same coolant passage design as a dosmetic NA V8 motor.

The other option is to remove the water pump and that's where most of the sludge ends up. The water pump passage has all the rusty sludge since the coolant swirls there.

fanbelted

well that kinda sucks! I guess a good time to clean the sludge would be when the water pump is replaced during a timing belt change