Just noticed this today, and I'm stumped. First, I noticed a spatter of coolant near the relief valve tee. Then, I noticed a drip of coolant from the tee with its source, the driver side coolant hose under an immense amount of pressure. So much that the line began to balloon. Then I inspected the other lines to the coolant, and they were also ballooning, but still no overheating. I then shut off the engine and opened the bleeder screw on the tee. Pressure slowly released as coolant squirted from the screw. After enough pressure released, I closed the screw, and could now squeeze the coolant lines and the reservoir level would change.

After letting it cool completely, I removed the coolant reservoir and bled the air from the system. No air came out.

Now, I'm sitting in Florence, OR, 300 or so miles from home and afraid to crank her back up based on what I've read in the forums already.

Any ideas? I'm stumped.

Oh yeah, this is my first post, but have greatly benefitted from fixing things based on useful forum info.

Thanks.

 

Welcome.
You cannot really tell if it is not overheating as the dash thermometer is crap telling nothing.
I would start the engine with no coolant cap and check for bubbles in there.

 

Thanks.
OK, so this is what I have done thus far.


Opened pressure cap on expansion tank after driving 11 miles. Lots of air under pressure escaped when I opened it.

Then, I started her up and found no bubbles in the expansion tank with the cap removed.

Last night after driving 11 miles with 300 ft elevation gain, I checked the hoses once we stopped.

Here is what I found:

The coolant pump feed hose and radiator top hose were stiff and hot>warm.

The radiator bottom hose was soft and cool.

All hoses, when squeezed, would force coolant into the expansion tank.

There is no water-rushing sound from the dashboard with or without the heater running.

The viscous fan does not have any wiggle or play.




My plan today is to change out the coolant. I've read mixed decisions as to which coolant I should be running. We're currently running the Orange stuff and its a bit diluted from the throttle body repair I did.

When I drain the coolant, should I refill with another Dexcool coolant, or should I switch to something like a Peak Extended Life?

Also, the D2WS manual calls for 3 gallons on refill. Is that correct? 3 gallons of 50/50 or 1.5 of concentrate diluted to 50/50 with distilled water?

 

Venture to guess the thermostat is not opening fully or the radiator has deposits.

I would not change/replace coolant, you may end with trapped air in the system, which you do not have now. But that is my opinion, (I run tap water in summer and antifreeze only in winter, as I installed an easy drain valve) and will be good not to waste new coolant until figuring out if you really have a problem.
There is a strong tendency in the forum to use Peak coolant instead.

You need a reliable thermometer installed

 

OK, so I will not change out the coolant.

I am going to drive 60 miles to Eugene so I can get a thermostat. I may be able to pick up a thermometer here, but I may have to wait until I make it to Eugene.

Thanks for the info so far.

 

Diagnose, diagnose first. Blindly guessing and throwing parts at it can be frustrating.

I would read coolant temperature first.
I would remove and test the thermostat first in boiling water to confirm it is bad before replacing, but that is me.
I would block/eliminate the bypass cooling path and evaluate direct flow to radiator only, but that is me.
Determining if a radiator is blocked by sediments is tricky, but has to be diagnosed.
Confirming the electric cooling fan operates is simple, has to be done.

 

This really bothers me :
----> Was that idling or engine off ?

With engine off, pressure must be the same at all hoses. If the radiator outlet hose is soft, it is a hose weakness. If the hose is weak, will collapse under pump suction and seriously restricting flow trough everywhere as these cars have no stiffener coil inside that hose. Goofy design.

If when idling, tells the radiator is doing its job, at least at a point of low flow when idling.

To diagnose that, with engine hot, observe the radiator outlet hose when raising rpm; must not deform. If it collapses, hose is weak, or radiator has blockage, or both.

Mine has an uncollapsible hose now.

 

Turns out all this had to do with the pressure cap. Thanks for the advice.