Mykl

From what I understand, there's a plug somewhere on the block that can be used to drain all of the coolant from the engine. I've never seen it though, would anybody know where it's at?

If not, could anybody tell me a way to get as much coolant out of the system as possible?

The heater hose that goes from the engine to the firewall blew out the other night on the highway and I'm waiting for the part to come in before I can fix it. While I'm in there I'm going to give the coolant system a good flushing to get as much **** out of it as I can. It has probably never been done in the 40k miles the engine has been in the car so it could probably use it.

The reason I want to be able to drain the block is because I'm going to flush it with tap water, but I'm going to fill it up with ~90% distilled water and ~10% antifreeze so I want to get as much tap water out of it as I can so I can get an accurate coolant mix. My reasoning for the 90/10 mix is because it really doesn't get cold enough in Alabama to really need a lot of antifreeze, and it gets hot enough down here to need a higher percentage of water because it transfers heat better. That and water is easier on the water pump than glycol is.

Thanks.

PraxRX7

Well I always just take off the lower rad hose and drain drain drain all day...flush flush flush, and fill fill fill...

However, I use a 50/50 mixture because I live in Canada and it isn't hot enough here to warrent anything higher than 50/50 (but I use water pump lubricant liquid stuff...)

Mykl

I imagine it would kinda suck if you used straight water and it actually froze in the block during the Winter.

SpeedRacer

Drivers side of the engine under the spark plugs...Keep in mind, that water has a lower boiling temperature than antifreeze.

turboconv

Its actually on the drivers side through the motor mount where it attaches to the engine. I believe it is a 14mm; it is a log hex thing about an inch and a quarter long.

dre_2ooo

Uhh... doesn't it say to use a 50/50 mix no matter what?

Ryde _Or_Die

So you take that bolt off, then what? Just let it drain by itself or do you have to use a pump or something to get all the anit-freeze out? Thanks.

Mykl

Where does it say that?

Mykl

Thanks, I'll look for that.

fc3s.org

Yeah Mykl, it is the same color as the weather treated steel parts on the intake manifolds etc.. That dull brown/yellow/bronze color LOL It looks just like a bolt head with no bolt. It is a 14MM and you will need a short socket for it or combo wrench. The motor mount gets in the way with a deep socket. Just take the plug out and open up one of the fill caps. What I do to flush my coolant system is disconnect the upper rad hose at the waterpump neck. Take off the thermostat housing and inspect/change out the thermostat. Drain the block. Then with a hose flush out the radiator and the lower block by pouring water down the hose from the water pump end. When it is clear, disconnect the lower hose and flush the block. Then I use that coolant flush addative with some plain water for the alloted time, then repeat steps and add new coolant with watter wetter. I use a 20%coolant/80%water mixture.

Mykl

I saw a diagram with that coolant plug, that's how I knew it was on the engine somewhere, but I wasn't sure where (couldn't remember) and my poor Haynes manual is virtually destroyed from all the use it's recieved. That clutch change on my GTU was just too much for it to handle.

Thanks for the tips on how to flush the thing. I've never done it before and I was just going to figure it out when I got there. Detailed instructions make it easier.

Evil Aviator

You may also want to check for an oil leak while you are at it. There are two O-rings under the oil filter base plate, and they like to crack and leak oil on that hose, which makes it break. The O-rings are really easy to replace, and even the Mazda dealership only charges a small fee for them.

Ryde _Or_Die

Hey evil, your from Riverview? I am right down the street. What kind & color Rx7 do u have?

Mykl

Thanks for the tip. While I'm down there I'll clean it up real good, run it, and check it out. If there is a leak it would probably be rather minimal since I don't lose much oil through an oil change, no more than it should anyway.

Evil Aviator

Well that's just it. When this happend to me, I couldn't figure out why my hose was breaking so often. The leak was very minimal, and I thought it was just some oil that I accidentally spilled when filling the engine. It's hard to notice the oil loss if you change the oil every 3,000 mi like I do. I think that mine started causing problems around 120K miles. You may not have this problem at all, but if you have a lot of miles on your engine and you have never replaced these O-rings, then you may want to shell out a couple dollars for the rings when you go back to pick up the hose that you ordered.

Yeah, I just moved back to FL last week. I'm staying at my parents' house until I find one to buy myself. I'll probably move to St. Petersburg or Tampa in a couple of months unless I take one of the two foreign job offers that I am considering.

In Riverview I have my faded-silver 88 TII with blue interior, and my 2000 F-150 which is white with a beige ricer-type stripe on the door. Do you know Scott Neville? My other two cars are at his garage in St. Petersburg. They are both black raced-out cars, one is an 84, and the other is an 88 (mostly) 20B RX-7 with a TII hood and red roll cage, belts, and seat trim.

What color is yours? Are you a member of http://www.mrccfl.com/ ?

Mykl

Well, put that way I may just do it for the heck of it for my next oil change.

Heh, I just keep adding more and more **** to do for my 10k tune up. I've got a nice long list built up. Hopefully when I'm done it'll feel as good as it did after the last tuneup.