coolant leak??

[ggleavitt]

Tons of incorrect information on these forums yet you felt compelled to go out of your way to correct my post?

Troll, get a life.

[chitownV]

Greg, it was the most recent post and a 3.2 post. Very very relevant. Not trolling as you have noted, your information was incorrect. I am glad the right information was shared by Paul so unnecessary work (plus parts) was not done in this case.

Sounds like you are taking over this thread and having a difficult time accepting that the information you provided was not the correct information for this thread. That's okay because other members have real-world experience with this.

A member was helped, helped with the right information, and avoided unnecessary work. Let's celebrate that.

Cheers

[ggleavitt]

That's been your closing narrative for a few years now. "Let's move on" or "time for you to you move on" or "we solved it for the masses so let's move on" whenever you decide the conversation is done.

It's kinda sad and hardly sustainable in my honest opinion but that's not all of your interesting personality quirks. Let me not ruin the surprise for everyone though, we'll let time provide the detail.

Cheers

[chitownV]

Sad the lengths you will go to. I hope you can accept you are not always right and accept when others have real-world experience. This thread is a great example of how important it is to have the right information and experience.

Take care

[ylwgto]

Appreciate the info, super helpful!

Some follow up:
1. Do I need to drain the coolant prior to changing this hose? If so, is there a procedure to avoid air blocks in system upon refilling (it is an issue with other modern cars...some require "burping" etc.).
2. I do not have any symptoms to suggest the thermostat is broken. What, other than being proactive, would be the advantage of changing it now?
3. Eyeballing it, now that I know how the hose connects, it seems that the manifold does not need to come off (which is great). Are there any other coolant hoses that I'd benefit from replacing while doing this?

Could do without the internal "banter", but I guess that is the nature of forums...hope you two can agree to disagree

[pgill]

Symptoms of a broken Thermostat

1. Insufficient Cabin heating in extremely cold weather

2. Poor fuel economy

3. Coolant leak

4. Poor running of the engine, premature wear of catalytic converters

5. Possible blockage of coolant flow and overheating


I purchased my S80 3.2 when it was 8 years old and I didn't notice any symptoms and when I removed the Thermostat it was already broken.

The return spring is constantly pressing on housing and the housing is plastic. Eventually the plastic fails. We can talk about cyclic fatigue loading or creep rupture but I doubt that you are interested in either topic. Lets just say that it is know to fail after about 10 years or 100,000 miles

Here is a picture or the broken plastic retainer




Here is a picture of a new Thermostat (if it fails where the red arrow is pointing then the coolant will leak out, this failure mode isn't common)





I don't recommend that you get an aftermarket part.

Get a new Thermostat from Volvo or Land Rover. Which ever is cheaper.

Good luck

Paul

[ylwgto]

@pgill thanks.

Great pics...I can see why that little plastic tab fails, odd design considering the stress it endures from that spring tension.

I indeed have a coolant leak and my fuel economy has gone down quite a bit (even after installing new plugs), so that is suspect.

questions:
1. do i have to drain the coolant to change the hose and thermostat?
2. to change the thermostat, does the intake manifold have to come off?
3. are there any other soft coolant lines that should be replaced while I am in there...or anything else for that matter?

much appreciated!!

[pgill]

questions:
1. do i have to drain the coolant to change the hose and thermostat?
2. to change the thermostat, does the intake manifold have to come off?
3. are there any other soft coolant lines that should be replaced while I am in there...or anything else for that matter?

A1. When you remove the large hose attached to the Thermostat a lot of the coolant will drain out. Some more will come out when you unbolt the thermostat. (Note: I drain mine using the drain at the bottom of the radiator)

A2. I prefer to remove the intake manifold, replace the 6 gaskets (Victor Reinz parts are inexpensive and excellent) and clean the throttle body. Having said that the XC90 has more room than my S80 and you may be able to replace the Thermostat without removing the Manifold.

A3. You are already planning to replace the part that is most likely to fail. Note: the S80 and the XC90 are different enough that I can't be sure that my coolant hoses are the same as yours so the best answer for this question will need to come from a different MVS member.

Good luck

Paul

[chitownV]

For coolant, it’s wise to change it since you will be draining a good amount and consider the age of the coolant.

In the XC90, I personally changed my thermostat without removing the intake since there is room. I had a small extension and can reach in there no problem. I might have used a flex elbow, but not sure. This also means you won’t need to get new gaskets and need to be mindful of the intake components breaking. I actually bought the Victor Reinz gaskets, but didn’t use them since there is room for the thermostat change. If you don’t need to open up a working system where you can potentially break small aged plastic bits, in this case the intake, then I suggest not to do it. If you happen to need to change intake gaskets later, it is completely independent of the thermostat.

There are a lot of hoses, including the main upper and lower hoses. I changed my upper and lower preventatively and be aware how they are connected, like if they use a clip and o-ring to seal. You will have to make that decision if you want to change your hoses.

[ylwgto]

Ok, thanks to you both! I will replace the thermostat when I do this hose and aim to not remove the manifold. Seems pretty straight forward.

I assume there is a drainage petcock on the lower radiator like most cars, so hopefully can drain from there.

Any special procedures with coolant replacement?
How much does the system take and any coolant recommendations (car is in Northern CA)?