I have a tiny problem with my 86 na, heres how the story goes, a couple of months ago i was making my 350 mile trip up to school. And i ran into some traffic, where i noticed my temps were extremely high and i pulled over and noticed smoke. I popped the hood and let it all clear. And i realized that the clamp had ate through on the coolant return hose from the heater core into the spark plug side of the motor. I cut it reclamped it since there was some slack refilled the coolant and i was on my way.
I thought that was the end of that until today. I was on the highway and hit some traffic and after a little bit i noticed my temps starting to climb and i thought it was normal since i was in traffic. After a little bit it started to get even hotter and close to overheating. I made it home and it was fully overheating. I popped the hood and it looks like the same thing. Im letting it cool off before i take a closer look at it but its coming from the same side of the motor and i think its the same problem. Does anyone know why this happens when i hit traffic? This was the first time i hit heavy traffic since the last time it happened. Anyone know how i can prevent it?
I have a koyo rad, and flex a lite electric fan, no ps or ac, very little porting, rb headers and a rb exhaust. Any advice is appreciated thanks in advance

 

check and see if the line is leaking again..i would replace the entire line and clamp...(correct me if im wrong)

 

Get a stronger rad hose and different style clamps. Btw over heating is a nono. It will warp the aluminum in the engine pretty damn quick.

 

yup...i hear ONCE and its over! so be extra careful with overheating problems.

 

See page 1-82 of the 1988 Factory Service Manual. There are two O-rings under the base plate for the oil filter. These O-rings crack over time, and slowly leak oil, which drips on the heater hose. After a while, the heater hose degrades, and it usually breaks first where the clamp digs into it.

I have a feeling that this is what is happening to your car. I recommend buying 2 O-rings, and replacing the old rings. Note the bolt torque in the FSM so that you don't ruin your car. You can get the O-rings from the Mazda dealership for just a few dollars. You will also need to replace the heater hose, which unfortunately isn't going to be cheap. Also see the FSM for the proper coolant mixture (use only distilled water) and coolant replacement procedure. You may also want to pick up a Mazda brand thermostat (don't ever use an aftermarket thermostat) if yours is still original, as this will soon fail if it is original.

FSM here under How-To's / Manual
http://fc3s.org/

 

yeah ive overheated twice now, but i survived the first i hope i survive this one. i dont think its the o rings i the oil filter, i just rebuilt the engine and i had those o rings changed, sigh its thats same hose. i think since i cut it the first time and since there is less slack now it rubbed through, it wasnt the clamp this time. Now im in a mad dash to find a new one or a used one till i get back to school and can get my hands on a new one... Does anyone think my local mazda dealer will have a new one in stock or do parts like these have to be ordered?