Klze in. Overheats at Highway speeds

mx3autozam · Post by **mx3autozam** » May 15th, 2006, 6:00 am

Ok My KLZE is in and runs great aside from a bit of a bad idle but that can be figured out. I can drive it all around town all day and beat the crap out of it and hit the redline all I want and it won't overheat. As soon as i get it going up to speeds like 120+ so lets say highway speeds and in 5th gear then the car will start to overheat. It won't actually overheat but the temp gauge gets right up to the Hot and coolant is bubbling in the reservoir and its right at the top. We put a new waterpump thermostat and head gaskets on the moror before we put it in. We also tried it without a thermostat and its doing the same. Also the rad fan does come on.It seems to always be on

Has anyone else had this or know anhything I can check???

2.5mazda · Post by **2.5mazda** » May 15th, 2006, 8:23 am

coolant temp sensor?

lakersfan1 · Post by **lakersfan1** » May 15th, 2006, 10:11 am

I'd guess bad headgaskets.

PATDIESEL · Post by **PATDIESEL** » May 15th, 2006, 11:00 am

Or bad head gasket installation. Have you ever done head gaskets before?

You may also need a new radiator. Your is most likely old and may have a partial blockage.

Other than that, do not let it start to heat up. The K series motors are VERY sensitve to heat. Find the problem and fix it before you take the freeway again.

ho bag · Post by **ho bag** » May 15th, 2006, 11:16 am

If the coolent is bubbeling then you either have a leak somewhere alowing air in the system, Bad head gasket instalitation letting combustion gasses in the coolent. Or something else i cant think of right now.

lakersfan1 · Post by **lakersfan1** » May 15th, 2006, 11:22 am

PATDIESEL wrote:Or bad head gasket installation. Have you ever done head gaskets before?

I didn't catch that he already did the head gaskets. Yeah. Step check:

1) Did you take the heads in to be decked?
2) Did you get the block checked for straightness and/or deck it?
3) Did you torque to 19 ft/lbs, then rotate all 90 degrees, then rotate all bolts another 90 degrees after that?
4) Did you makes sure the mating surfaces were clean down to metal with no dust or particulates on it?
5) Did you use a copper gasket spray?

gsr-se · Post by **gsr-se** » May 15th, 2006, 3:40 pm

While the car is running, open the rad cap...if u see bubbles come to the top, its the head gasket.... U could drill holes in the thermostat to make it run cooler.... Possible the rad is blocked? Possible low rad fluid? Does it leak rad fluid at all? Check for puddle after it sat and has cooled down.... WATER WETTER claims to run cooler too....Hope these babblings of mine helps out

2.5mazda · Post by **2.5mazda** » May 15th, 2006, 10:24 pm

bubbling does NOT mean you have a bad head gasket. Mine bubbled, and it was because there was air in the system from topping it off or refilling it. Once you let the car run with the cap off and the bubbles quit comming to the surface then you know that the air is out of the system and you can put the cap back on. I know this for a fact because I just had to do it 2 weeks ago, my headgaskets were fine, I had a real test done on that with this colored dye stuff although I dont know how that works.

ho bag · Post by **ho bag** » May 15th, 2006, 10:46 pm

But if the bubbles dont stop.......

2.5mazda · Post by **2.5mazda** » May 15th, 2006, 10:48 pm

still, not reliable enough to tear your engine apart over....

ho bag · Post by **ho bag** » May 15th, 2006, 11:42 pm

Fine, do a compression test and a leak down test.

mx3autozam · Post by **mx3autozam** » May 16th, 2006, 2:38 am

I have done head gaskets before. I never used a copper gasket spray.

The mating services were cleaned perfectly. Had it also checked for straightness and was fine. It overheated today in the city. Let it cool down and got it home and its just sittin there. Driving the work truck around now. I'm gunna look intosome stuff and possibly tow it to shop and get some tests done.

I've also heard water wetter helps alot.I used that in my last car. never had cooling issues with that car though. Regardless I will be using it either way once I figure out my problem.

John

BTW: There is a slight miss at idle. I think its the ignition timing off a bit. Gunna fix that and see if that help[s it. My dads car had overheating problems and that was part of the reason