280z Cooling system mystery

[925280z]

36 minutes ago, siteunseen said:

That new belt may have ruined the water pump?  Hopefully not but I've read where the tightness of the belt ruins the old bearings in the pump.

Checking the fan clutch is a good suggestion.  See how many rounds it'll turn by spinning one blade by hand.  Shouldn't make a complete rotation if it's cool.  It is oil filled and gets looser with heated up oil.

If the bearings are bad in the pump you'll be able to hear something rattling or the blades scraping the inside of the housing.  I shouldn't have mentioned that, sorry.

do you think with proper belt tension this problem would go away motorsport auto claims that there should be 3/4-1 inch of belt deflection

[siteunseen]

Fan clutch sounds okay but does it make a louder noise like a constant "whooshing" that stays loud?  They can go bad in the opposite by constantly turning.  They normally make noise at first then quiet down when the oil heats up. 

Try it looser as msa says but I've always ran mine tight.  If you bought it from msa it should be the right belt.

Some smarter guys/girls will jump in soon with other ideas. 

I get tunnel vision too bad.

[925280z]

also my warm up tens to be a little slower as in once it hits 140-145 i stays there for 2-3 minutes then the temp gauge slowly starts creeping towards 180, then in about 45 seconds it creeps to 225 which is my new operating temperture

[siteunseen]

You may have bought a cheap thermostat?  Did it start running hotter with the belt change or did you do all of this at the same time?

Gotta run now but will be reading your thread.  Best of luck finding the problem. 8^)

[925280z]

4 minutes ago, siteunseen said:

You may have bought a cheap thermostat?  Did it start running hotter with the belt change or did you do all of this at the same time?

Gotta run now but will be reading your thread.  Best of luck finding the problem. 8^)

it was after the belt change when the symptons started

 

[siteunseen]

Seems to me that you have the belt too loose or too tight? or the wrong width belt and it's slipping on the water pump pulley.

I know you don't want to but if you have the old belt I'd put it on and see if the problem is still present.  

[Dave WM]

ditto, put the old one on since that is when the prob started.

[siteunseen]

Also I would park it somewhere that wouldn't cause any trouble getting coolant, like out in the dirt, no puddles for animals or leave a mess and do like Mr Overlord says in post 3.  On a cool motor with no tight radiator hose from pressure, take the cap off and stick a meat thermometer down in it.  It'll burp up a little but should smooth out after the thermostat opens.  You should see a decent flowing over the top row of cores.

[925280z]

5 hours ago, Reptoid Overlords said:

Perhaps the first thing to do would be to verify the coolant temperature by checking it hot with a meat temperature gauge or something of the sort.

Sent from my N9130 using Classic Zcar Club mobile
 

 

1 hour ago, siteunseen said:

Also I would park it somewhere that wouldn't cause any trouble getting coolant, like out in the dirt, no puddles for animals or leave a mess and do like Mr Overlord says in post 3.  On a cool motor with no tight radiator hose from pressure, take the cap off and stick a meat thermometer down in it.  It'll burp up a little but should smooth out after the thermostat opens.  You should see a decent flowing over the top row of cores.

well do i have some info for you guys haha , when it reached its new operating temperature i saw no coolant flow at the cap just steam ! and not even a lot of steam im talking a little bit more than bare minimum i think were on the right track also my lower radiator hose does show sign of flow but the top takes forever to show signs of flow 

 

 

Edited February 24, 2017 by 925280z

[Reptoid Overlords]

It looks like the car started running hot so you replaced the thermostat. Otherwise I would say pull it out and boil it in a pot on the stove and observe it opening. It sounds like this all started before the new thermostat. Maybe boil it anyway just to verify it isn't defective just to rule out a faulty thermostat and troubleshoot from there..

Sent from my N9130 using Classic Zcar Club mobile

[Zed Head]

The overheating could be coincidental to the belt swap.  No cause and effect.  Belt and fan problems would show up at idle, like at stop lights, or slow driving.  Radiator problems show up at highway speed.  Thermostats affect both.

The "haha I only saw steam" comment sounds like you don't have any coolant in the system.  You didn't' really explain what you meant.  Are you saying that the radiator is not full?  That could be the whole problem right there.

[925280z]

2 minutes ago, Zed Head said:

The overheating could be coincidental to the belt swap.  No cause and effect.  Belt and fan problems would show up at idle, like at stop lights, or slow driving.  Radiator problems show up at highway speed.  Thermostats affect both.

The "haha I only saw steam" comment sounds like you don't have any coolant in the system.  You didn't' really explain what you meant.  Are you saying that the radiator is not full?  That could be the whole problem right there.

the full story is that after i did my belt change it started running hotter , i changed the thermostat and no luck , ive been observing the car all day and the symptoms appear as soon as the car gets to operating temperature i thought maybe it was a faulty coolant temp senor ( the one that allows my gauge to work but i got confirmation that it wasnt the case it was marking 240 when i parked my car at my college and the engine was steaming . i tested the fan clutch and it was ok its just weird how it suddenly started running hot , i only drive from my house to my college which is a 10 minute drive on a bad day and by the time im parked the car is at 230-240 . i just observed how my cooling system behaved and the lower hose was showing signs of pressure but the top hose took FOREVER to start showing signs off pressure . im really trying to pin point the problem before i spend a dollar , i really dont want to take it to a shop so they can throw parts at it . id rather find out exactly what it is and fix it in my auto class.