Engine Coolant Drain Plug Location?

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Mr2Owner
Posts: 123
Joined: Sun Nov 29, 2015 7:39 pm
Location: Ireland

Engine Coolant Drain Plug Location?

Post by Mr2Owner »

I'm going giving my Rev3 Mr2 turbo a coolant change and flush, can anyone tell me or even better throw up a pic of the engine block drain plug. I know from searching the forum its a 14mm socket bolt and its on the passenger side of the engine apparently.

I can't find it though, is it visible/accessed from below the engine or above the engine?
If someone could throw up a pic it'd be great. :)
mr2magic
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Re: Engine Coolant Drain Plug Location?

Post by mr2magic »

The block is not the best place to drain coolant from if your going for a complete flush. You need to use the lowest point in the whole system. Thankfully Toyota thought of that and placed drain plugs in both heater pipes running under the floor pan. Remove the two underbody covers, take a 12mm socket and get ready for 13 liters of coolant :-)
markstevieandmads
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Re: Engine Coolant Drain Plug Location?

Post by markstevieandmads »

Be careful with this though. Due to the heat cycling both my drain points snapped off. I ended up draining everything from the front of the car. Took ages but just kept flushing until water was clear then topped up.

Don't forget to follow the bleeding procedure too. I found I had to drain,refill , bleed it then take it for a blast getting it up to temp then bled again. It was fine after this.
Mr2Owner
Posts: 123
Joined: Sun Nov 29, 2015 7:39 pm
Location: Ireland

Re: Engine Coolant Drain Plug Location?

Post by Mr2Owner »

Cheers for the tips, Little update, I've drained the radiator and the 2 drain points on the pipes under the car but I've only collected about 8 liters of rusty old coolant so far.

I've the car level, then i jacked up the rear of it up real high and tried a few different things, drained another bit from the radiator again.

Wheres the rest of it hiding, I've a new thermostat for it too so when I remove the old stat I'll probably find more coolant to drain then, but I'd rather find the engine drain plug first to avoid a mess doing the stat and also to catch as much of the old coolant as I can to gauge how much I get out of the system.

Can anyone tell me where this engine block drain bolt is, is it accessed from above or below the car?

Edit: I found the drain eventually, accessed from under the car, left it draining slowly so will measure all I got out of the system later on.
Mr2Owner
Posts: 123
Joined: Sun Nov 29, 2015 7:39 pm
Location: Ireland

Re: Engine Coolant Drain Plug Location?

Post by Mr2Owner »

I've gotten 10 liters of coolant out of the car, glad I found the engine drain plug.

Anyone want to point me in the direction of the thermostat now :lol: It wasn't where I thought it was.

Is it in the water pump? If so, where is the water pump, does the timing belt drive the water pump on these cars?
mr2magic
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Joined: Fri Apr 09, 2010 9:33 am
Location: Hannover, Germany

Re: Engine Coolant Drain Plug Location?

Post by mr2magic »

First off I'm surprised you got more coolant from what you call the engine drain plug - the two plugs i told you about are the lowest points in the system. Assuming you opened the coolant cap and the rad bleed valve there should be no coolant left if drained from those two plugs ;-)

As to your question - the thermostat is inside the housing next to the oil cooler/warmer by the downpipe. The large rubber coolant hose that connects to the steel hardline that runs underneath the car (from which you removed one drain plug) is also connected to this housing.
jimGTS
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Re: Engine Coolant Drain Plug Location?

Post by jimGTS »

Just because the coolant hardpipes are the lowest point doesn't mean you'll get everything out.

There is a reason there is an engine drain plug.
Also given the thermostat is closed when cold might have something to do with it. :eye:
mr2magic
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Location: Hannover, Germany

Re: Engine Coolant Drain Plug Location?

Post by mr2magic »

I hear you.....nevertheless I've always done it that way an never had any noticeable rest in the block...? Whatever works is right i guess :-)
Mr2Owner
Posts: 123
Joined: Sun Nov 29, 2015 7:39 pm
Location: Ireland

Re: Engine Coolant Drain Plug Location?

Post by Mr2Owner »

mr2magic wrote:I hear you.....nevertheless I've always done it that way an never had any noticeable rest in the block...? Whatever works is right i guess :-)


Did you ever get the full 13 liters out of the car by draining it alone, or did you have to flush out the rest. With all 4 drains undone I only got 10liters maybe 10.5liters.

I reckon my remaining coolant is in the heater, perhaps I should have taken the 2 pipes off in the engine bay and flushed water down them.


I bled it there today, didn't bother with the thermostat in the end as when I seen its location I wasn't gonna get the car up high enough so decided to leave it as its not broken anyway and wanted to get the car refilled and bleeding done. It bled ok, followed the procedure in the manual someone here linked me to. Brought it for a spin and temp sits at half way and heater has heat so seems fine. Ill just add a drop of coolant to the expansion tank tomorrow when its cooled down fully.
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