I car is having some overheating issues. I just got the motor rebuilt about 3k miles ago and now it's giving me problems. The other day on my way to work, the temp gauge started to go up and immediately went down. I figured the thermostat was messed up. I went and replace the thermostat and put in a Koyo radiator, and a new radiator cap. I also depressurized the system to make sure no air was trapped in it. I'm still having cooling problems. It seems that after the car warms up, most of the coolant is shot up to the overflow tank and it overflows and spills all over, leaving little coolant in the motor, and I have to refill it everytime I start up the car or it will cause it to overheat. I'm completly clueless on what else could go wrong. I was thinking the seal, but the motor is too fresh, IMO.

 

Who rebuilt your motor? Does it have a warranty?

 

..take it back to where you got the rebuild. I would put all the stock things back on it thought. If it was done by a mazda dealership they fu#$ you if its not stock.

 

Do you have the stock AST? Because if you do, it's a common problem for people to switch the caps from the filler neck to the AST. The one on the AST needs to be the pressure cap with the spring. The one on the neck just needs to be a cap.

It sounds like your boiling, which means the cooling system isn't under pressure, which means you have a leak somewhere. Possibly a bad coolent seal which would really blow if that were it and I would hope you have a warranty.

I just picked up my FD from a guy in Texas and had the same problem. Ended up being the caps like I described. If I didn't work on FD's already, that would have been a huge towing bill from Texas to Colorado.

 

aint that a sign of O-ring failure? dont think they rebuilt it

 

what temp are you running? if you dont have a water temp gauge, why the hell not? your risking your newly rebuilt engine on something which cost like 50 bucks from any autostore in the US!

BTW: not everyone builds good engines, humans make mistakes and something a fraction of a mm off can cause a leak unfortunatly...

 

take it back to the shop have them pressure test it and trouble shoot the problem. are the fans engaging?

 

It's possible it's an O-ring, but there are so many other things that it could be. You should just have the whole cooling system checked out before you deam a bad motor.

 

oh, i just remembered something, you might have an airbubble in your waterpump, to get that out, go back to the shop and have them vaccum out everything (including air) and then allow the coolant to flow back in, it might take a few times to actually do this if you have a bad airbubble some place. goodluck

 

I had a similar problem. Nothing luckily was seriously wrong. All that was wrong was that the radiator hosing would come loose and leak fluid. You should double clamp these hoses. especially the ones closer to the base of the radiator. Make sure you have a decent coolant/purified [bottled not tap] water ratio. The less anti freeze to higher water ratio when it gets warmer out is better. If you don't have an aftermarket high end temp gauge. get one.

Running the AC reduces power but sets the fans on earlier. It's simpler to just leave your parking lights on. not your blinkers and not the headlights. This also triggers the fans to come on earlier. So if your temp spikes flip either switch.

With rebuilds or reman's or in my experience. If you notice some gunk in your coolant reseviour don't freak out. I was told it is typical because of some lubricant or something they use in the rebuild. I'm hazy on what it is exactly. But check your coolant regularly. make sure clamps are tight. Freshly placed hoses seem to come loose because i believe heat and time usually makes the rubber stick and seal better around piping. Don't be shy to carry bottles of water to top your car off.

I have an ast deletion. It works. If you don't have it get it.

Burp your radiator hosing like skunks says.

listen to madlist and all the good advice.

Try not to be cheap or try not to cut any corners.

Autometer gauges aren't very accurate. spend 50 more bucks for something good.

learn the metric system

Take it back to the shop, and risk looking stupid instead of risk detonating.

goodluck

 

I am not using the AST, so that's not the problem. I also depressurized the system with this tool that sucks all the air out of the system to make sure no air pockets remain. I did pull the rear plugs and the were bone dry. Someone told me that if they were wet it's an easy hint that the seal went. No I don't have an aftermarket temp, gauge, I was actually going to buy a handheld for my Microtech so I can monitor just about everything on there.

 

If you've eliminated the AST, what type of cap are you using at the filler neck? At what pressure does it open? Sounds to me like the system is not holding pressure. O-ring failures are typified by a small amount of coolant being pushed out of the system, not the large amounts he seems to be indicating.

 

Turned out to be the rear seal to be the problem. Looks like the motor is getting pulled out once again....

 

Awe,
Sorry to hear that Rey. Fuego should hook you up though because the seal is so new.
I will see you this weekend at the meet.
Don't start the rebuild untill after the meet...you have one of the better looking FD's around here.

Raj