# 89 Nissan 300ZX Overheating



## LAB (Aug 9, 2004)

I have an 89 300ZX non-turbo that is overheating after about 45 min of running. I have changed the radiator, fan clutch, upper and lower hoses, thermostat and still nothing. I don't get any heat out of the heater either. ANy thoughts? Some told me that if I had a couple of bad injectors that it would overheat. Thanks in advance for the help.


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## asleepz (Feb 24, 2004)

The engine block ports are clogged. RIP HER DOWN!

Post this in the Nissan Z forums next time too


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## LAB (Aug 9, 2004)

SKD_Tech said:


> The engine block ports are clogged. RIP HER DOWN!
> 
> Post this in the Nissan Z forums next time too



WOW. That's pretty harsh. Is there any less extreme way to fix this problem? Will a back flush or other procedure work? Don't know if the cost of "Ripping her down" would be worth it.


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## asleepz (Feb 24, 2004)

Hmm. Take off the radiator hoses and pull out the thermostat and let it run with fresh water (from a hose)go through it. It worked for me but mine wasn't a big blockage. Do the same with your radiator. Try that


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## LAB (Aug 9, 2004)

Thanks. How hard is it to remove the thermostat? It was changed by a local mech and I can't ever remember seeing it?


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## asleepz (Feb 24, 2004)

You have to take off the idler pulley for the AC compressor off and then it is in plain view (4 bolts or less I think)


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## Harris (Nov 11, 2002)

Move thread to appropriate area.


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## asleepz (Feb 24, 2004)

thanks Harris


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## Zen31ZR (Mar 24, 2004)

Harris said:


> Move thread to appropriate area.


 Where was it.......


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## asleepz (Feb 24, 2004)

NA forums


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## LAB (Aug 9, 2004)

Well the continuing saga of the 300ZX overheating continues. It now apears that the only unchanged part in the cooling system is the water pump. We have determined that there is no water circulation or very poor circulation. While this might very well be due to clogged engine ports, the water pump is an easier task then ripping the engine open.

That being said, we started disasembeling the front end of the motor. The question we now have is that to get the lower timing belt cover off you have to remove the pully assembly off the crank. Is this correct? If so, is the pully slid on with a keyway or does it need to be pulled off with a puller.

thanks in advance for any advice. 

Might as well change the timming belt as well.


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## LAB (Aug 9, 2004)

Cause of the overheating was the water pump. Every fin off the pump was broken off. All fins have been accounted for.


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## Zen31ZR (Mar 24, 2004)

LAB said:


> Cause of the overheating was the water pump. Every fin off the pump was broken off. All fins have been accounted for.


:cheers: At least it ended well.


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## asleepz (Feb 24, 2004)

At least you got all the fins. Good job. I never would of thought that would happen


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