Stupid NA problem
 

I just wanted to state that the little rubber nipple on the back of the head that covers an unused coolant port is the stupidest thing ever to be included on any car ever. I have consistently replaced mine every six months for the past three years now. You would think that someone would think to NOT just plug the darn hole with a rubber cap... I'm now buying packs of four because I will inevitably have to do this on the side of the road roughly twice a year for as long as I own this car...

That's really odd...

When I had the head off of my '92 a few years ago, and went ahead and replaced that cap just because it looked a bit crusty. Wasn't leaking, and I'm pretty sure it was original.

The replacement hasn't started leaking yet either.

If you're going through these caps that rapidly, something is wrong.

You've replaced the cursed water plug regularly - when is the last time you replaced your radiator cap? How are you securing the rubber cap to the pipe? That little pipe probably made sense in the original configuration of the engine.

Edit: Are you using a generic cap, or Mazda OEM?

I've been using a generic replacement and have been careful not to overtighten the clamp. I just put in a new aluminum rad a few months ago and it came with a new cap... relevance for rad cap? I assumed that when it was in the previous car/configuration it was used. It just stinks getting stranded twice a year... I keep hoping the replacements will last longer than they do. Actually now that I think about it the first time I replaced it was back in 2007....

Radiator cap relevance: if your radiator cap is not letting pressure out, it will build up behind that plug.

You are replacing these every 6 months because you're using generic caps. You may very well be using vacuum nipple caps.

If you want 15 years out of this instead of 6 months, buy the correct part. And you may value putting the Mazda spring clamp on too.

Yup.

This is one of those rare cases where I strongly advocate the use of OEM hardware. It's part number FEA7-13-104, and if you're too lazy to drive down to the dealership, you can get 'em for $5.95 from Rosenthal: http://finishlineperformance.com/sto...cat=319&page=3

While you're back there, install a new spring clamp as well. It's P/N JF02-15-538.

Thank you! I will be getting both parts in the very near future. It completely makes sense to replace the broken part with the right one... Thanks guys.
Ben