My Fiero hasn't leaked coolant since last winter when I replaced the hose connecting to the thermostat. Recently I've noticed I've been losing coolant and it's gotten to the point where it will leave a noticeable trail once warmed up. I'm in college so I don't take it on very long trips unless I'm heading home but yesterday I noticed it dripping more than usual and it was coming from the front of the car beneath the radiator. Today I was able to check the hoses and they seem snug. The plastic radiator plug in the bottom passenger side corner was my only other real suspect. I attempted to tighten it but when I did coolant started to flush out and it wouldn't tighten. I wasn't sure if it was a screw or a valve so I backed it out completely to realize it indeed was a screw. I then reinserted it and tried to tighten it but it seems stripped or something. The threads on the screw are perfect. It still seems to steadily drip when the car is running. Does anyone have any ideas? I tried to search about the radiator drain plug but didn't find much helpful. Also, the radiator is only two years old. Thanks!
The body can be replaced. It's designed that way so that the radiator doesn't get damaged. Grab and squeeze with a pair of needle nose pliers and pull it out. It's recessed almost to the square hole in your diagram. Once you've compressed and pulled it out about 3/8 inch, you can grasp and squeeze it with your fingers to get it completely out.
I don't have a spare one to check, but I think the only thing is the flat rubber washer seal. I don't believe there's an O-ring on the stem. Pegasus, if the threads on the stem aren't stripped, be sure the base is fully inserted into the radiator. It must be fully inserted in order for the seal to be captured between the stem cap and the sealing surface inside the radiator.
[This message has been edited by fierofool (edited 10-26-2014).]
Thanks for the replies! It was hard to diagnose in the parking lot with just a socket set but I think I may try to get it home this weekend to get underneath of it and check it out. I thought I pushed it in pretty hard but may not have. If I need a new plug has anyone seen this type before. All the ones I find for the Fiero don't look like the one I have.
Well I found the culprit. The leak was indeed coming from the drain plug. Funny how things break a few weeks after the radiator's 2 year warranty. The drain plug is two pieces and the clip that the plug screws into was cracked causing the plug to be unable to thread in and tighten. Unfortunately, the clip is a very odd plus (+) shape and none of the parts stores had anything that would work. On the bright side I was able to contact the radiator manufacturer, Spectra Premium, and they are sending a replacement drain plug to my house for free. If all goes well I'll head back home next weekend and install the new plug and put the radiator back in. Gotta love plastic parts!!!
Agreed, ogre and reinhart. I've never touched the knob, but while working on my front end I noticed that the plugs handle was bent and broken. Touching the thing revealed the plastic was cheese - apparently from glycol penetration into cracks in the injection molded silcock ends.
Luckily, I was able to fish out the 'bits' of goopy plastic, flush the radiator a bit to remove any lost solids, and replace with Dorman 61109 - dimensions were identical to the old plug, and installed fine!
Good coolant mix won't cause most problems. But... Weak or No coolant Will. Examples: Even people using 50/50 mix after flushing cause problems because water trap in the block etc causes weak coolant. EG and PG in coolant isn't only thing in them and doesn't wear out, spoil, or whatever myth but anti rust and other chemicals do Wear Out. Weak coolant to Plain Water will attack many parts not just cause "rust" for Iron and Aluminum.
If the drain "plug" parts are bad... WP Seal may have problems too. Coolant is lube to WP seal. Likely has things to protect plastic... If coolant doesn't have a "plasticizer" then likely still tries to stop soft parts like WP seal leaching out the "plasticizer" they have.
I've never seen one before but it looks like it'd be impossible to damage the outlet tank by overtightening it. The threads are not part of the tank but part of the drain plug. That makes me less hesitant to remove the plug if I needed to. I don't believe the outlet tanks are sold separately anymore so if the tank were damaged from even something silly light a drain plug the whole radiator would have to be replaced so good thing it doesn't seem to be an issue.