Ok, so I bought the car yesterday and drove it 200 miles home. No problem, saw a tiny coolant leak before i drove it. Nothing happened, it stayed cool the whole time. this morning i was working on it and no sign of the coolant leak. drove it around 5ish, to the store, gave it a little gas in third gear. Now, when i started it to go home tonight, it was 40ish outside, and its stumbled a bit, especially when i wanted to start out in first, the moment i let the clutch engage and gave it some gas, stutter city. started on my 1 mile home, but let it warm up for a few minutes. my choke seems to be stuck, then when i pull it all the way out it boggs the car dead. so i start it back up and hold the gas down to about 1.5k rpms. start driving home when i notice it getting hotter than usual, its normally about 1/6 the way up. creeped to 3/4 of the way before i shut it off. opened the hood, and there was only a little coolant leak.puzzled me, but i remembered not to run a rotary hot. so i let it sit there for about 10 minutes, and started off (i know that wasnt long enough). drove a few small neighborhood streets before turning it off again. repeated that process about 3-4 times before i got home.

What could be wrong?

Thinking about doing a coolant flush tomorrow, so :

1. im thinking about pulling the hoses off the rad tomorrow and sticking the garden hose in the block's upper hose and shooting water through the block, hopefully it is a stoppage somewhere. would that hurt the engine?

2. If i did the same to just the rad, would that hurt it?


Does anyone know if this is common, or what could i do?

 

You need to be more exact as to where the coolant is showing up. Good call on shutting it down as soon as the gauge moved past the 1/2 way mark. However, 10 minutes cool down time is not enough, In that time frame, the block and coolant goes into heat sink, thereby stabilizing a uniforn temp throghout the entire block and radiator.

In the future, please state the engine series and any mods, helps online troubleshooting.

Not knowing the mileage or the length of storage time, it's usually best to due the full 60k mileage service before driving the car much. This will give you a chance to become more intimate with your new love. It's also a way to look over the vehicle for other potential problems. A thorough engine cleaning prior to start will help too. Coolant flush is a good idea, be sure to follow the instructions on the bottle.

Causes of overheating can be, but not limited to:, stuck thermostat, (use Mazda oem ONLY!), plugged radiator core, timing is off, cats are plugged, minor coolant leak, bad waterpump, radiator cap is bad, oil level is very low, etc..

Clean the engine bay, do the full 60k service, (NGK or Nippon Denso plugs only), look for coolant and oil leaks.

After doing the service interval and looking it over, post back and be more spedific.

Welcome to the Darkside. In my sig line is a link to the online FSMs and other pertinant publications. last line in the sig,is my ongoing project, they are never done.

 

so you have any pics yet??

 

It is a 1979, 12a (of course). will get pics/more info when i get home. basically, i saw a little stream coming off near the last part of resevior hose on top of the rad.

 

ok, pics:

 

Also check the Fan clutch. If it was fine at freeway speeds but you were in town under 35mph and getting hot. It could be the fan clutch is not engaging.

 

In the 2nd picture it looks like you have a new Radiator and Hoses or a recently serviced cooling system.
Tighten all the clamps!! (Not too tight) cause you can damage the inlets. (They Bend Easily).
Take you garden hose a mildly sparay down the top and bottom of the Rad and Hoses. Let everthing dry. Start car let warm up look for leaks.
If you decide to flush the system go ahead and replace the Thermostat like Mr. T suggested (OEM) only.
Have Fun with your new toy.
sgieldon
steve

 

er.

 

Thanks for the advice! took the garden hose and hosed the dried fluid away, then leaf-blowed the rad dry. turns out the clamp in the second pic was tight, but not too tight. loosened it up and coolant started seeping out (and by seeping i mean coming forth with massive velocity) so i scooted it up and retightened it. drove it around the neighborhood with rear defrost on and AC on max/hot. everything went fine!

Thanks again everyone... sorry for the stupid question, this is my baby, and that was her first problem

 

Make sure that your belts are properly tightened too. Slippage of the belt that runs across the water pump can cause overheating issues...

 

Jeezus,
Glad to hear it was an easy fix.
sgieldon
steve

 

AAAH! problem came back! Im starting to think that its the cold weather for some reason, both overheating problems happened late at night or early in the morning.

im thinking that my gauges are stuck, because when its cold outside the rear latch doesnt want to close and the hood is hard to open

 

Have you replaced the thermostat with a Mazda unit yet?

 

Not yet. I added water to the coolant resevior tank yesterday, then it overheated, now there was barely any in the tank and it didnt overheat. Going to see if it overheats once more. i know i have a coolant leak but i do not know where yet

 

can you see the coolant on the ground after you drive the car? is it coming from the same place? have you inspected the water pump weep hole? you may also have an air pocket in the system. have you tried burping the air out?

 

i dont know how to burp it out yet. i think its coming from teh same part, the upper hose of the radiator on the passenger side. thing is, it overheats sometimes and not others

first overheat was when it was 12am, i would say 30*F outside. weird idle, but let it warm up. overheated.
second overheat, this morning. about 7:30am, about the same temperature. same thing.

 

I read somewhere about the lower part of the radiator being cold when the car is overheating means a new thermostat is in order, but when my car started to overheat, i let it reach 1/2 way and turned it off. felt the radiator... the whole thing was cold.

 

Sounds like the thermostat is bad and not opening up. Replace it with an oem Mazda one only and make sure you install it correctly.

 

Ok, costed me 18$ for the mazda OEM thermostat and gasket. followed the Haynes manual for replacing it to the t, and it STILL overheats.

I love this car but I hate it so much.

 

welcome to the club my friend, but one thing is for sure: when its good its amazing

 

Yeah, I just cant wait for this "good" to happen

 

Change your temp sender yet?

 

I have no clue what that is... sounds expensive :p

I just want to be able to drive the car when it is cold outside.

come to think of it, is it this?

 

How did you verify that it is overheating?

 

temp gauge would skyrocket after about 2-3 minutes of warmup and 45seconds to a minute of driving. I dont think it would be the temp gauge as it works fine when it is warm outside. I am just afraid of thinking that the temp gauge if faulty and the cold makes it haywire, then find out it isnt and burn the motor up.