OK so went for a longer test run and it did get really hot (boiling hot)...
So go figure i think it might be the water pump....
Then when it start cool down i start hear a frizle bubble sound by the water pump... WHAT IS IT? Should i replace the whole water pump?
Other question what the thing in front of the radiator (it look like a other smaller one...)Oil cooling ? Why is it not hot after the engine was over heating?
Any advise?

 

Oh and the round disk at the end of the Cooler compressor is loose and wobbles is that normal :/ ??? Sorry if i sound like i don't know anything about z's well i DON'T... I just know how to wrench...

 

Bearings in your water pump are bad. Get a new one.

If you have AC, it's most likely your AC condensor.

Depends on what you mean by "Cooler compressor"?

 

I think it is the A/C condenser clutch...

 

I am going to change the water pump and see if that solves the problem...

 

I hope you have small hands!

I removed my radiator and A/C so I could get a wrench in there without bloodying my knuckles up.

Oh, and most parts stores still carry that water pump.

 

Ok so got the new pump now i think i might try to put it in myself...you say got to take the rad off? or could i do it bloodying my knuckles up? Basically...can it be done without taking out the rad and A/C out ???

 

Yes, it can be done without pulling the radiator and the A/C. I've done it a couple of times. It's tight, but it can be done. It's easier if you have long handled open end wrenches so you can keep your knuckles out of danger, or you can just wear a pair of leather gloves...

 

I am wondering...can i use just water in the radiator or do i have to use coolant?

 

you can just use water, especially since i doubt freezing is a concern in Hawaii. but coolant helps to cool better, and also has anti-rust compounds. it's always best to run a proper mix of coolant and water.

 

Still over heating after flushing the radiator and changing the pump...so now i think its the radiator....

 

In your previous thread, you said you replaced the radiator cap. Did you buy an OEM cap? I had this same problem once before because I bought an aftermarket cap. The OEM cap solved the overheating problem.

Also, at what point is the car overheating? Does the temp gauge go back down when the car is moving, and up when the car is sitting still? Do you have your A/C on when this occurs? I'm wondering if the problem is the fan clutch. I had that same problem also. After replacing every other freaking cooling part, including the radiator, it was the fan clutch that was the culprit.

Radiators are much more expensive to replace than the fan clutch. Can you give us more info. by answering my questions above, and maybe we can help pinpoint your overheating problem?

 

Car overheats after 3 miles of road time going 35-45 MPH....
It stays cool when it just idles before i drive it but after i drive it around it wont
cool off... seems like i am getting poor circulation i took out the thermostat to see if the water flow got better but not really i think there might still be some thick slime stuck in the small channels of the radiator and there might be a pin hole in it...What is a OEM cap cuz i think i got just a regular aftermarket cap.
So i started by new CAP then new THERMOSTAT,WATER PUMP,SPARK PLUGS,AIR FILTER, next thinking HOSES,RADIATOR,FANCLUTCH... what else could i do?

PS: I don't think the A/C works... does the A/C affect the cooling of the engine?

 

Your radiator just might be the problem, I don't know if it's as common on the 280ZX, but I know on the 300ZX people generally would have a lot of overheating problems which turned out to be just the radiator.

 

Could be the fan clutch...something had to make the bearings in the pump go bad. Also don't over tighten the belt either...that will wear out the bearings quickly. Oh and if your heater core is not bypassed under the hood check for moisture on the floor boards. If it is leaking that too could help it overheat.

 

How do you bypass the Heater core?
That whole thing don't work...just got the car so seems like the whole heating-cooling & A/C system is malfunctioning...

 

No, the A/C doesn't affect the cooling of the engine unless it's running and putting a greater strain on the motor.

The fact that you've removed the thermostat and replaced the water pump, pretty much rules those out. The next real possibility is the fan clutch and then the radiator.

When you pulled your spark plugs, did any of them look "steam" cleaned? If one or two of them were VERY clean, it could indicate a blown head gasket.

Before you go down that path though, you should see if you can rent a cooling system pressure tester from your local auto parts store. It's basically a small bicycle pump attached to a modified radiator cap.

You install the cap with the connector for the air hose on the pump, pump it up to 16 or 18 psi, let it sit for a few minutes and see if the pressure has bled off. If it has, that means you've got a leak in the system somewhere. ie. heater hose, radiator hose or head gasket. Hopefully, you'll be able to hear a hissing sound giving you an idea of where the problem is.

If pressure hasn't fallen off, it usually means coolant is not properly circulating through the system for some reason. ie. water pump, fan clutch or radiator.

Check your Haynes manual or Factory Service Manual and they will go into great detail on how to test the cooling system.

Cheers,
LWW

 

Alright so tomorrow i am going to order a radiator and buy a fan clutch....then will she how she run's...

 

Before you throw away another couple hundred bucks, borrow or rent a pressure tester for $10 or $15 first. Randomly throwing parts and money at the problem isn't usually the best way to fix it.

 

Well, it almost worked for me!



Rod.

 

Shut up Rod!

 

Yes going to get new hoes's too;-)
Got to get all new parts that the way when you are rebuilding....

 

What was it in the end....???