The matter in the bottom of my tank had become very hard and crystalized . I had to chisel it out of the tank with a screwdriver and ream out the hose coming out from under the tank with a hand auger from LOWES for sinks then flushed the system and refilled. That worked for me. See the fluid could not return to the engine after being pushed into the expansion tank which would just overflow if the cap wasn't on tight. Now it all circulates fine.

 

yeah mine did the same thing, and it was just the thermostat

it's a five dollar part, with two torx screws. go ahead and do it, it'll take 5 min


my money is on the thermostat too

 

Tech/Jim
I was thinking about this comment I made. Is this correct? Is it normal for this to happen? Maybe my 850 has excessive pressure in the cooling system if it spits out when I open the expansion cap.

 

hi again,
still the same problem, as before.... i have coolant leaking off the expansion tank.
what is the term for the head gasket, do u know where i can buy one.
wen i search all i get is the cylinder head gasket...wat is the radiator one called?!

also where is the head gasket located at?!

tanx heaps

 

Did you get a new expansion tank / expansion tank cap / thermostat?

If you have to do the head gasket get your wallet ready.

http://en.wikipedia.org/wiki/Head_gasket

 

If you need a new head gasket, look at spending about $1500 even if you do the work yourself and it's not an easy job.

axelm, yes you will get some pressure in the expansion tank, but not a tremendous amount. I can losen mine slowly and lose next to nothing.

 

Are you saying that you can use the car during summer, then park the car, shut the engine off, open the expansion tank slowly and almost no coolant will come out?

 

no one should do this. severe burns can occur due to steam and hot liquid splashing out at you!!!!

 

+1. I just want to know if I have excessive pressure in my cooling system. Jim says he can open his expansion cap without any coolant loss. Mine spits coolant like a soccer fan spits at the referee.

 

My wife just got home about 1/2 hour ago. I'm going to go take the cap off and see how much pressure. I'll be back.

Very little pressure and it was warm, but not hot when I took it off. I can't say I ever just stop the car and take it off. I have done that with older cars and you need to be very careful and use a thick rag, but that was when it was a radiator cap not an expansion tank cap, and you have to just barely open it to relieve the pressure.

 

Jim, thanks for the test results.

I wonder what happened to AIX. He has not posted any more replies on this thread.

 

ive had it gush all over the place on a 97 960...so dont get too confident just because it is an expansion tank instead of a radiator cap.

 

hi all back, had a busy week at wrk...[&:]

i was driving in traffic yesterday and i saw steam coming out of the engine, wen i popped the hod up and cheked the expansion tank, it was BONE DRY!!! so i filled it up with water and drove home...

any way, i am trying to get a volvo mechanic to check it. EXPANSION TANK HAS GOT ALOT OF PRESSURE BUILD UP!! - it gases up? all i hear wen the engine is warm is gas expelling from the expansion tank....
i just bought sum coollant gonna ,gonna take the car to a mechanic to check the 1] thermostat 2] pressure testng 3] change the coolant...

- i have realise that the old coolant is so dirty and brownish looking.... iam so confused?![:@]

 

You need ASAP to change:

expansion tank cap
thermostat

I would also change the expansion tank itself and the engine coolant temperature sensor.

YOU ARE RISKING YOUR ENGINE DUE TO $20 IN PARTS THAT YOU CAN CHANGE YOURSELF IN 30 MINUTES.

 

i have noticed that I am also losing coolant but cant find where it is going. Some white smoke comes out of tailpipe, but not always. it usually takes about two days of 60 miles of driving per day for the low coolant light to come up. what should I look for if there are no apparent leaks under the hood?

 

Any smell when you turn the heat on?

 

none

 

tech, this was directed at you. No smell when it is turned on. as a matter of fact, i think the car has been doing this for a while cause when i fill up the expansion tank, i hardly see any color...guess i should just flush, refill and see what happens...???

 

I would get the system pressurized and try to find the leak.

 

gut news, i took the car to a volvo mechanic on saturday,

the mechanic
1] checked the expansion tank using this gas detector/sniffer thing, the computer analysis didnt show any sign of gases -no gas = no broken gasket [sm=smiley20.gif]
2] he removed the expansion tanks cap, using a pump/ pressure monitor he pumped the expansion tank

RESULTS =

using method 2] he discovered that the expansion tank is cracked from the top [cap area].
i ordered a expansion tank $98.00 aust. dollars, toped it up with sum coolant and hooked up the expansion tank &THE PROBLEM IS GONE [sm=smiley32.gif][sm=closed.gif] thank you all for ur helps & comments...