Pokin' around under the hood, trying to decide if I want to change out the water pump (which of course it's suggested you do the fan clutch as well) while doing the thermostat and hoses; I saw this new development...



It had not been leaking before- did take a 20 mile drive yesterday, first long distance since purchase.


"One thing leads to another... But then one thing leads to another..."

 

Tricky diagnosis. Could be just the clamp or the hose leaking. Easier replace than the other stuff. Metals still look healthy to me. Think positive...!

 

Oh, I am. Just looked, it's dry and I drove it today, but not yesterday. It really looks like it's from the gasket itself.

 

When you replace the thermostat gasket do the head to housing gasket as well. If one is leaking the other is most likely going to leak too.

 

Dumb question- what's the head to the housing? The top cover over the t-stat?

 

Are your working with your FSM? Most parts are shown and labeled in your diagrams. Maybe Sec LC...

 

Yes, I do use the FSM, just not during work hours... Upon referring to the FSM, 1+1 make 2 and I see what audio was indicating, thanks. I'll get the other gasket when I pick up my lower rad hose, which will be tomorrow.

I am not a mechanic, but I'm mechanically inclined.

 

Great! That means you can do it all your way. Be sure to report back when you make a discovery or solve a problem. We can use feedback here! Photos always welcome!

 

Went ahead with changing out the t-stat and rad hoses. Didn't do the housing to head gasket, because of reading several posts about busting the sensors while removing them. Besides, upon inspection, the t-stat housing itself needs to be replaced, as well as the lower rad hose engine fitting. As the pics show, they are pitted/corroded.

<a href="http://s1259.photobucket.com/user/TheBravenewme/media/2014-05-24_09-41-40_261_zpsb4fd599d.jpg.html" target="_blank"><img src="http://i1259.photobucket.com/albums/ii552/TheBravenewme/2014-05-24_09-41-40_261_zpsb4fd599d.jpg" border="0" alt=" photo 2014-05-24_09-41-40_261_zpsb4fd599d.jpg"/></a>


<a href="http://s1259.photobucket.com/user/TheBravenewme/media/2014-05-24_10-22-36_615_zpsbb17b540.jpg.html" target="_blank"><img src="http://i1259.photobucket.com/albums/ii552/TheBravenewme/2014-05-24_10-22-36_615_zpsbb17b540.jpg" border="0" alt=" photo 2014-05-24_10-22-36_615_zpsbb17b540.jpg"/></a>

<a href="http://s1259.photobucket.com/user/TheBravenewme/media/2014-05-24_10-01-45_604_zpsde4edb7e.jpg.html" target="_blank"><img src="http://i1259.photobucket.com/albums/ii552/TheBravenewme/2014-05-24_10-01-45_604_zpsde4edb7e.jpg" border="0" alt=" photo 2014-05-24_10-01-45_604_zpsde4edb7e.jpg"/></a>

<a href="http://s1259.photobucket.com/user/TheBravenewme/media/2014-05-24_11-07-59_678_zpse5731a47.jpg.html" target="_blank"><img src="http://i1259.photobucket.com/albums/ii552/TheBravenewme/2014-05-24_11-07-59_678_zpse5731a47.jpg" border="0" alt=" photo 2014-05-24_11-07-59_678_zpse5731a47.jpg"/></a>



Unfortunately, we're still running too hot, and the dashboard system indicator light now shows the "water" signal.
So... looking for what you all have tried:
Flush the radiator: how and what has worked/not worked- home vs pro.
Pull it and have it rodded.
Install a new one.

The exterior of the rad looks great, no damage to the fins, no leaks. BTW, if this is the original radiator, what type were they, steel/copper or aluminum? Thanks in advance...

 

Based on what you say, I would take it to a pro radiator shop for inspection and testing, assuming there's one in your area. They have the experience to figure out what you need. The ones around here are pretty informal and easy to deal with. Two of them only do radiators. You are sure your water pump is in good shape, right?

 

Is there any way to tell w/o taking it apart? Just from perusing past threads, I'm planning on doing the pump anyway...

 

If you can stop any leaks that are preventing you from filling the radiator, just fill the whole system up so you can see a steady water/coolant level in the radiator with the cap off. 1/2" to 1" deep"? Stick your finger in. You may have to idle the engine to eliminate any air in the system.

When you have a cold system completely filled, leave the cap off, start the engine and watch the flow happen as the motor idles. With Z31s, you see it running past where your finger was/is. Hit the accelerator and the flow increases. That's a good water pump doing what it should.

 

Update on the overheating issue: I did change out the water pump, wasn't rusted, but it's movement was stiff. Also ran some prestone cleaner through the rad then straight distilled H2o. Flushed it out, then 50/50 using distilled. My temp gauge has stayed below the midline since. The new development, is a leaky heater core. Hoping I don't have to pull the dash....

 

It's rarely the actual heater core. 90% of the time it's the water valve (****) plunger that's leaking.

 

Thanks Nismo, I've spent the better part of the evening scrounging the forum and one of the last posts I read said the same thing.
Earlier, I took out all the removables from the the passenger side (where the coolant was coming from) and got lost. Would it be easier to see it from the drivers side?



I'm not a mechanic, but I'm mechanically inclined.

 

Let me know if you need a radiator down the road. Because I scored on a 3 core aluminum Silla one for less than $200. There is a shop in downtown Mesa. Ever since I installed it, my temp rarely goes past a quarter and half. And things I have learned about these cars. Is if your cooling system is not up to par. You will have all types of over heating issues. I have pretty much dealt with and fixed all of them owning multiple Z cars. lol

 

Question: In replacing the water valve (****) plunger w/o removing the dash, I'm figuring I need to remove this (heater blower?)
<a href="http://s1259.photobucket.com/user/TheBravenewme/media/photobucket-17464-1405190954689_zpsd3c0d32a.jpg.html" target="_blank"><img src="http://i1259.photobucket.com/albums/ii552/TheBravenewme/photobucket-17464-1405190954689_zpsd3c0d32a.jpg" border="0" alt="2014-07-12 photo photobucket-17464-1405190954689_zpsd3c0d32a.jpg"/></a>

to get to this...
<a href="http://s1259.photobucket.com/user/TheBravenewme/media/photobucket-1555-1405192294424_zpsd3d379a5.jpg.html" target="_blank"><img src="http://i1259.photobucket.com/albums/ii552/TheBravenewme/photobucket-1555-1405192294424_zpsd3d379a5.jpg" border="0" alt="2014-07-12 photo photobucket-1555-1405192294424_zpsd3d379a5.jpg"/></a>