I've got a bit over 2K miles on my Mazda reman and noticed a small puddle of coolant under the car the last few times I've driven it. I can't really tell where it's coming from although the lip of the oil pan seemed wet. Doesn't seem to be coming from the coolant hose/fitting near the oil sender. you can see in the pic the puddle is under the left motor mount.

Please tell me this isn't a bad coolant seal....

 

A bad coolant seal can lead to the overflow tank spilling coolant on the ground, but that's located on the front passenger side of the car. You'd also get white smoke out the tailpipe.

I'd start checking all your hoses, like the lower rad hose and the hose to the block you already mentioned. Also, check that the drain for the block is on tight....it's a 14mm bolt on the intermediate iron. I think I can see it in your picture actually

 

Check the hoses going to the throttle body.

 

The good news: coolant seals usually leak internally, so that is probably not the problem.

The bad news: you'll just have to try harder to trace it down. There are several hoses that could result in a puddle forming in that area. As Rich said, it could be coming from the engine drain plug. Coolant could drip on the subframe and wind up there from some relatively far-away leak. Look for whitish or greenish trace of dried coolant higher up on the engine, or do a coolant pressure test.

 

Interesting... my first impression was the leak was coming from that 14MM bolt on the intermediate housing. But the engine was warm enough that after one swipe of the moisture with my finger it completely dried. I'll climb under tomorrow, remove it and put some sealant on and reinstall.

I'm hoping I'm just paranoid since I lost my original engine to coolant seal failure.
The plastic Rad inlet nipple cracked, hose blew off and I overheated. Iknow the symptoms and the cars not exhibiting any of them.

 

I wouldnt recommend removing the bolt, unless you plan to drain your system and burp it of air. Also, sealant isn't needed. Just make sure it's tight.

 

kf3er, I guess you purchased a reman to replace your previous engine that suffered coolant seal failure? How long ago did you get the reman? Or did you purchase this FD with the reman already in it?

 

I purchased the reman to replace my original engine. Igot the Reman from Ray at Malloy in Oct 1996 but didn't finish installing it until June 1997. The original had 80K miles on the odo when it went. I bought the car new in 1995. I've got 82K on the chassis today.

 

Check the quick disconnect on the driver side of the rear engine iron, where the heater hose connects. Very prone to leaks and what appears to be your problem in the picture. Report back



Later

 

So if I read that correctly, you put 80K miles on the car in one year and then 2k miles on the car in 10 years?

 

Yeah, that is what I am confused about too.

 

Was Ray even selling remans back in 1996 ?

 

I am pretty sure he meant 2006 and 2007 but wrote 1996 and 1997 in error. That would make a bit more sense.

 

Man, it's that new years change thing! I meant to type I bought the reman in Oct 2006 and installed it in June 2007. Sorry for the confusion.

 

That's what I figured you meant. I hope you trace down the problem and it turns out to be minor. Happy new year!

 

Good news! Rich nailed it (thanks Rich). The block drain plug on the intermediate housing was loose. Cinched it down and took the car out for some more tuning runs. Got home and let it sit for awhile and all is well.

Jeeze I was worried there. I've just about got my PFC (AFR's) dialed in and I find this crazy coolant leak. I was havin' some bad visions....

I really want to thank the people on the forum for all their kind help.

 

Great! Glad it was that simple!

Dave

 

Nice, glad it was something simple . Happy New Year!

 

Good news.

 

FYI overflow spilling can also be caused by a faulty AST cap and not just the coolant seals. Mine spilled coolant all the time till I figured it out. Everything was perfectly fine after replacing it.

 

Next time save yourself all the diagnostic trouble and go to Advance Auto to rent a coolant pressure tester. Pump the pressure to about 17-20psi. If there is any external leak, it will be obvious. This is the fastest, easiest, and safest way to fine any leak. When you rent the tools, it only cost you when you get them. You get a full refund when you bring it back.