Leaking lower radiator hose, boil over
 

Hey guys I have an 05 rx8 mt. I noticed 2 days ago that I was leaking coolent. I found the source was my lower radiator hose. Then I noticed I had dryed splashes on my airbox, battery tray and my engine cover. I going to replace my hose on my next day off bit I wondering what's causing all of this. The car has never over heat but cAn't know for sure because my dummy gauges wouldn't tell me much unless something severe happeans. I think it might be my thermostat. I touched both hoses to see if one was hot and the other cold but my engine bay is always hot and both hose were hot. How can I tell if my thermostat is bad? I want to take the opportunity to replace it if it's bad. I also going to be doing a 70/30 mix because I live here in miami and it's always hot as he'll. Any thoughts or advice on my problem? Please help

the thermostat should be fine. just replace the hose. the splashes might not be coolant.

The engine bay smells of coolent.I'm just worried about it because I don't want this or any other hose leaking or poping. I drained all my coolent to today and it looked clean. No gunk or surprises so I don't think it's my radiator.

the splashes that you saw might came from Overflow tank short hose. when the system goes over 0.9 psi (stock cap pressure), it releases pressure by releasing coolant out.

Coolant hose is a wear item, dont expect it to last the life of the car :)

if its me I will replace them every 40K miles just to be safe.

I would change out the other 2 at the same time to be safe......

i would change the car to a new one just to be safe ... :rofl::rofl:

Well my plan is to change the lower one first since I already bought it then see how it goes. If no other problems arise then I'm going to get the 3pc silicone hoses and also the mazmart waterpump.

On a side note, when I was under my car I noticed my tranny was leaking fluid also. I only have 48,806 miles and I'm leaking everywhere. Is this normal?

You are kidding, right? :SHOCKED::scratchhe

No, it's not normal. Yes, you should figure out why it's leaking. Yes, you should fix it (or, have it fixed) asap.

Hope this helps.

i have a 3 piece silicone hose kit for sale. $75 shipped. PM me if interested.

After I fix the hoses, I'm going to take it this rotory machanic. I can't fix it myself. I just had the transmission fluid changed a few months back. I did it at a jiffy lube. I guess that don't know what they were doing.basterds!

so this is what i found when i removed the hose.corrosion on both ends of my lower hose, but no rips or cracks..i don,t understand why it was leaking.the clamps was on tight also.my only assumption is that my thermostat was closed and would rise the pressure causing it leak and thats why my reservoir would boil over..am i correct? but wouldnt i over heat? any thoughts?

Doesn't matter, it shouldn't leak at the hose unless the clamp is insufficient for the job. If you see it visibly leaking from it, get a better hose clamp and tighten it down. Otherwise, when it overheats if too much coolant goes in the overflow it can go out the vent hose, that's it. Only other possibility is a slit in the hose aka cut from the clamps. Ask me how I know. I wound up having to cut the hose shorter to get rid of that section but the best way to fix this is order the new hose from a dealer to fix the problem. Generally they cost anywhere from 20-45 depending on the hose that has to be swapped. That and get a hose pinch-off pliers to work on it so you don't have to drain the entire system. I plan on getting this in the future with the mickey mousing I've had to do with aftermarket adapters used in-line.

While your at it.. replace the water pump.

Frankly, I have never liked the Hose Clamps Mazda uses, they are a quick and cheap production type...

The best hose clamps are the Worm Drive - Band Type Hose Clamp which can also be purchased in stainless steel. They seal far better with a more even pressured around the entire 360 degrees of the hose.

You can see the cheap OEM Mazda ones have a very small area where the hose has little to no pressure applied by the clamp, this is usually where coolant will start to leak or build up a leak from.

https://www.rx8club.com/attachment.p...1&d=1253824441

you get those hoses i sent you?

Hope what happened to me didn't happen to you.

Replace your water pump ASAP.

Same think happened to me except I didn't replace my water pump soon enough. When I did get to it, 3 of the 4 fins on the stock WP were "missing" and there was a ton of orange reside all throughout my hoses and coolant lines. That residue was the corroded remains of those 3 missing fins.

Flush your coolant system thoroughly. Your boilover problem may indicate a blockage or obstruction somewhere.

Good luck.