MX-3 Overheating

[yankeex777x777]

Hi, i have a 93 mx-3 V6 (also one of the lucky 3000 to get the limited edition )but as of the past 3 or 4 days after i drive it for 10 minutes, the temp gauge shoots all the way up, i see visible smoke comming out of the hood, and exhaust pipe. So i checked the fluids, and the coolant levels are full, and i just added 2 quarts of oil...im not due for an oil change for another 1000+ miles. I'm baffled right now, i dont even know where to start.... I know its overheating, i just dont know why, please help.

[perhapsadingo8yerbaby]

Sure sounds suspiciously like a blown head gasket allowing coolant to seep into a cylinder (only takes a tiny droplet) which vaporizes into billowing white smoke (steam) coming out the exhaust pipe. Similarly, superheated coolant may be under pressure coming out from the head gasket seal (cuz it no longer would be providing a seal between the block and head) which could account for white "smoke" from the engine bay. You say you added 2 qts. oil (that's a lot) and checked coolant levels.

What did the coolant (in the radiator, not the expansion reservoir) & oil on the dipstick look like? Normal colors or kind of a grey putty color? If grey/putty in color, that indicates a head gasket is blown as well as maybe a head has warped if enough extreme overheating has occurred, and your coolant and oil are contaminating each other by mixing to produce that grey sludge. Any of this description fit your situation??

BTW, it's VERY bad to ever let your temp gauge "shoot ALL the way up", as high enough temps can warp metal which was what I was referring to when speaking of a warped head. Post back, I'm curious now to hear whatcha find. Please don't totally freak out cuz of my post. There will be plenty of time for that later if needed...

<small>[ June 28, 2004, 12:56 PM: Message edited by: perhapsadingo8yerbaby ]</small>

[yankeex777x777]

Nah, i just chekced it, no greysih lookin color to the oil it looks normal, where do u check the radiator at? cuz the reservoir where the coolant is at, is full...still lost on whats wrong

[perhapsadingo8yerbaby]

Good on the oil color/consistency check although sounds like it got awfully low-you should check your oil level more frequently. If your coolant looks good, you probably have a worn out thermostat which is a $6 part and a 20-30 minute max job to replace. If you didn't see a large amt. of steam literally billowing from your exhaust pipe, it's possible the overheating engine (cuz of a stuck/worn out thermostat) was introducing enough steam into the engine bay that your air intake was pulling some thru the engine & out the exhaust.

With the engine totally cooled off open/twist off the radiator cap and look into the radiator itself. Just trace the hose from your expansion reservoir back to the radiator/cap-you'll see it. You should see nice liquid green coolant at a level just under the filler neck that you removed the rad. cap from.

Safety tip! Do NOT try this on a warm/hot engine or the hot coolant will spray out under pressure when you remove the cap and any that gets on you will remove your skin or burn your eyes out of your head if it sprays into your face. Nuff said on that (I hope... )

You can leave your hood up to allow air circulation so the engine will cool down faster if needed and if there is any doubt on whether it has cooled enough, turn your key enough to activate your gauge cluster (but not start the engine) and make sure your temp gauge reads cold. Also, always a good idea to wad up a towel/fat-rag in your hand to ensure no hot coolant sprays you just in case it is still too warm.

Sounds like you're new to engines. Hope my info isn't too oversimplified. If it is, no offense, just lemme know.

<small>[ July 05, 2004, 06:24 PM: Message edited by: perhapsadingo8yerbaby ]</small>

[yankeex777x777]

It was a blown hose, was a real ***** to get at too, had to take out the whole right side of the engine, batt, air filter...but i did it myself and only 12.50 at ur local auto parts store
car runs liek a gem tho, no cpmplaints

[Ainu69]

Well my friend, it looks like you have either blowen your tempeture gauge that regulates the amount of coolant that goes into the engine.

About 8 months ago i had the same problem and for me it was my radiator went, it would continue to overheat every 3-10 minutes. i checked the car and found out i had no coolant and i just recently got back from kamloops i think i was driving my car with no coolant and blammy blew the cylinder on the side of the radiator, and $300 later it was replaced and fixed the problem.

So either its your radiator or your tempeture gauge.

all the luck
chris

[perhapsadingo8yerbaby]

Originally posted by Chris Avvvv:
It was a blown hose...

Happy for ya to hear it was that simple a prob/cause for the hot engine. I just assumed you had checked your cooling sys hoses already and were looking at additional possible causes. Damn, my fault cuz you know what they say when ya A$$-U-ME something. That's on me tho bro. Glad you're rolling again and no head gasket damage from the overheating either.

<small>[ July 01, 2004, 07:09 PM: Message edited by: perhapsadingo8yerbaby ]</small>

[Franko]

I had a overheating problem in the past, as it turns out the first and only winter the car was driven in snow blocked up the cooling fan and burned it out. I didnt realize anything was wrong until I would stop and idle for a long time. The heat would shoot all the way up. There should be a warning light or something that would let you know if your temp is too high.. I only recently got the fan fixed because of the precious bpt. i drove the car with the fan broken for like a year..

[seneca]

I have an overheating prob. with mine aswell! It's also a '93 GS (not the se, lucky son of a... :p ) lol But lately she just seems to heat right up. Not quite to the red but pretty close. There's no smoke, and I try not to run her to hard on a daily basis. I'm thinking it may be a possible temp sensor. Other than that, I'm lost.

[perhapsadingo8yerbaby]

Originally posted by seneca:
I have an overheating prob. with mine aswell! It's also a '93 GS (not the se, lucky son of a... :p ) lol But lately she just seems to heat right up. Not quite to the red but pretty close. There's no smoke, and I try not to run her to hard on a daily basis. I'm thinking it may be a possible temp sensor. Other than that, I'm lost.

Thermostat is most likely worn out and as your engine heats, thermostat is sticking mostly shut so your coolant just sits in the engine, heats up and can't circulate to/thru the radiator to be cooled and recirculated back thru the engine. Not unusual to have a thermostat go bad once in a great while... $6 part from any autoparts store, 20-30 minute job to replace it. You're running some serious risk of big-time engine damage if you let the thing run too hot...

<small>[ July 04, 2004, 05:23 AM: Message edited by: perhapsadingo8yerbaby ]</small>

[Nd4SpdSe]

my thermostat went on my ze in the winter, now it was winter so i didn't have any overheating issues, but it took as damn long time to get upto regular running temp, and it only put out warm air...but from what i experienced, a bad thermostat would do the complete opposite from overheating

[millionflame]

Originally posted by Franko:
There should be a warning light or something that would let you know if your temp is too high.

Doesn't the Check Engine Light come on once the engine is too hot???

[perhapsadingo8yerbaby]

Originally posted by Nd4SpdSe:
my thermostat went on my ze in the winter, now it was winter so i didn't have any overheating issues, but it took as damn long time to get upto regular running temp, and it only put out warm air...but from what i experienced, a bad thermostat would do the complete opposite from overheating

Sounds like your thermo went bad by sticking open instead of sticking closed that's all. That would allow the coolant to circulate before it reached operating temp. Seneca's situation is the opposite and probably has nothing to do with a bad sensor although that's always a possibility. The sensor sounds to be working fine as his temp gauge reading is consistently telling him something like... "I'm gonna blow this mofo engine up if ya don't replace that thermo bro."

[seneca]

I hope there is a how to on changing a thermo. in the FAQ.

[perhapsadingo8yerbaby]

Originally posted by seneca:
I hope there is a how to on changing a thermo. in the FAQ.

Dunno about the FAQ but it's a straightforward repair. Was the first repair I ever did on the first car I owned. Do you have a Chilton's or Haynes manual for your car? If not, you should pick one up as it's well covered in there. Best $15 you'll ever spend and will end up paying for itself many times over. The basic steps:

1) Disconnect the negative battery cable.

2) On a cold engine, drain the radiator enough so the coolant level is below the upper radiator hose.

3) Follow the upper rad hose to the metal housing/cover it's attached to. Your thermostat is in that housing.

4) Put a rag under the housing to catch any small amount of coolant that comes out. Remove the two thermo housing mounting bolts. Ya might hafta remove the upper rad hose first to have room to get at the bolts. Don't know about 93's but on 95 GS models, if you hafta remove the upper rad hose where it connects to the thermo housing/cover, there's an o-ring Mazda says you'll need to replace.

5) Remove the thermo housing & pull out the thermo. Take note of the direction the thermo is mounted in cuz your new one must go in oriented the same way. Also, if your replacement thermo has a "jiggle pin" the thermo should be installed with that pin at the top near a small projection notch that the gasket fits into.

6) Remove/clean off any old gasket material from the housing mating surfaces. Go easy with something like a clean smooth (no nicks) putty knife edge if needed to remove any old stuck-on gasket material. You wanna have smooth clean dry surfaces free of nicks/scratches where the new gasket will go.

7) Apply a thin bead of permatex semipermanent gasket sealer to both sides of the gasket (or housing mating surfaces) and place the new gasket in position.

Put the new thermo in place and installation is the reverse of removal. Torque the housing mounting bolts to spec. (19-25 N-m, or 1.9-2.6 kgf-m, or 14-18 ft-lb)

9) Add coolant directly to the radiator to bring it back up to full. Replace the radiator cap, start the engine, let it get to operating temperature and observe for any leaks around the thermo housing and/or hose fittings. If you see leaks around the thermo housing, go back to step (1) and start over.

This all really sounds more complicated written step-by-step than it actually is. If you still have any doubts on doing it yourself, have a mech do the job or get the repair manual, which will provide some helpful diagrams/pics and will explain other stuff like how/where to drain your radiator etc. Or, post back with specific questions. You can do this bro.

<small>[ July 08, 2004, 09:08 AM: Message edited by: perhapsadingo8yerbaby ]</small>