Radiator Drain plug or lack thereof

[andyl]

I went to flush the radiator on my inherited(came with wife) 1994 MX-3. When I got underneath to the drain plug(lower right = passenger side), I saw there wasn't one. Surprised I found this forum and noticed on the forum that they have a habit of breaking. Well this one just wasn't there. I can see right in and put a screw driver in the hole. The car runs fine, no signs of overheating and there is fluid at the cap, in the upper hose and in the reservoir. I'm confused as to why its running fine, why there is no plug and why there isn't fluid everywhere. I'm looking for somebody to educate me on this?

[Zoso124]

Do you have a digital camera? take a pic, I'm really curious.

[andyl]

I'll try to get the picture tomorrow after work and post it.

[Steeb]

i was in an accident taht smashed my radiator. after all the coolant drained out i drove home fine for about 20 miles. when i got home i popped the hood and there was no fluid in my radiator. the engine temperature stayed normal and i could have kept driving, althought its probably not good, but my starter failed. dont know why but it happened to me too

[mxer4eva]

Speaking of drain plugs, has anyone drilled theirs out and replaced it with a bolt or something? Let me know im really looking for a way to make my already broken plug functional.

thanks

<small>[ November 04, 2003, 05:34 PM: Message edited by: mxer4eva ]</small>

[mitmaks]

i need to find out how u drain it too, i mean if u take it to dealer or tune up shop what are THEy will do? im sure they wont drill hole how you replace fluid in there, thats stupid designed radiator, prob one of things that i odnt like about my mazda. i need to flush mine soon.

[Spydie]

you can go through the trouble of removing the block heater, then jam a hose into the rad fill cap and run the water hard until it comes out clear.

[potatochobit]

if the plug fell out recently your system is still pressurized and water will slowly drip out, but wont gush out. once you take the upper radiator cap off, it will pour out.

[PATDIESEL]

Are you sure that you weren't sticking the screw driver into the radiator support and not the drain plug.

[IanL]

Originally posted by potatochobit:
if the plug fell out recently your system is still pressurized ......

This puzzles me. What retains the pressure when the plug has gone?

[andyl]

Thanks for the inputs. Mike tipped me off to something and looks like the situation arose from a radiator repair done back in '99. I drained/flushed the rad by removing the lower hose and am not going to worry about it as long as it keeps running as well as it is.

[zevirii]

My rad. has no plug either.. Makes me wonder if it was repaired or replace before? hmm

[Gro Harlem]

I tried figuring out how the h*ll to drain my radiator when I did my motor swap. I couldn't figure it out so I just removed the lower radiator hose from it instead.

According to the FSM, the plug is on the side of one of the endtanks. I looked at it and saw it, it was some flimsy POS plastic screwnut that was already stripped to the point where no screwdriver could get on it. Worthless design!

My Protege at least has the plug on the bottom, which is a plastic wing-nut style plug that is easy to get off.

[Chino921]

I don't know about everyone else, but my radiator has a drain plug on the right (passenger side of the car) front, lower corner. It's a plastic 10mm bolt.

And no, you can't just drill a hole the radiator and put in a bolt (unless you tap it and use JB weld and plan to never drain it again). The stock drain plug should have a rubber o-ring to seal it.

[Bri94GS]

They sell kits at Pep Boys or Autozone that let you drain the coolant through the place you fill it under the hood. Some sort of suction mechanism.