A hole on the top of coolant expansion tank

bobice · Post by **bobice** » 14 May 2011, 20:39

Found a little hole on the top of my coolant expansion tank. The hole is small. What could happen to the cooling system?

Also can I just use regular hose clamp for the bleeder hose? Didn't find the clamp from Fcpgroton.

Thanks in advance!

el diablo viejo · Post by **el diablo viejo** » 14 May 2011, 22:54

I have had the occasion of being to two boneyards this week and almost every Volvo I saw still had the expansion tank still on it, although many were missing the cap.
My advice would be to just go pick up a used reservoir tank and grab another Volvo clamp while you're at it.
For the couple of dollars it's not worth having to think about a hole in the tank.
When you pull off your old reservoir tank, check the bottom hose. I found mine had been rubbing against the large air hose underneath it and consequently had been worn thin in one spot. I think this is common on the S/V 70 setups.

Post by **Ozark Lee** » 15 May 2011, 06:34

A new replacement isn't that expensive, I just had to buy one for my daughter's S70 and I think it was under $30.00. Standard worm gear hose clamps are just fine on both hoses.

The new tank had reinforced tubes on both the main hose and the bleeder hose, all of mine have broken at the bleeder hose nipple so the metal reinforcement is a huge upgrade.

Running without the system getting up to pressure can allow the coolant to boil which, in the popular vernacular, is a "Bad Thing".

Also check your cap, the old Gray caps all split but the new style Greenish Blue caps seem to hold up. They too are cheap in Volvo terms.

...Lee

bobice · Post by **bobice** » 15 May 2011, 06:59

Thanks for the information. New tank for 99-00 V70 seems to be a little bit more expensive at ~$40 plus shipping. Good thing is that my current cap is green, so I guess the cap and the bleeder hoses might have been replaced before, thus I'll just order the tank itself. The hoses feel solid still to me. Thanks again.

bobice · Post by **bobice** » 26 May 2011, 09:29

I replaced with the new OEM tank, however, the float inside the tank does not move up to the top most position. I tried using a forceps but still didn't help. Is it bad float? I am using Zerex G05.

Thanks.

Post by **jblackburn** » 26 May 2011, 09:41

Is the low coolant light on? As long as the float isn't sitting at the bottom of the tank and tripping the sensor, I don't know that it matters.

bobice · Post by **bobice** » 26 May 2011, 09:51

jblackburn wrote:Is the low coolant light on? As long as the float isn't sitting at the bottom of the tank and tripping the sensor, I don't know that it matters.

Yes, the coolant light is on. The float isn't at the bottom, so that means the sensor might not be installed correctly? I heard a clip when I put the sensor in the hole so I assumed it snapped in.

db130 · Post by **db130** » 26 May 2011, 23:02

it's possible that the coolant level sensor died while changing the reservoir(it happened to me once).

bobice · Post by **bobice** » 27 May 2011, 08:27

db130 wrote:it's possible that the coolant level sensor died while changing the reservoir(it happened to me once).

Is there a way to test it? Such as measuring the resistance? Thanks.

db130 · Post by **db130** » 27 May 2011, 09:03

i'm sure there is, but the fact that the light is on even though the float is working correctly is a dead giveaway.

*edit - take the sensor out of the socket on the expansion tank but leave it plugged in - is the light still on? most likely it will be, because it has died.

the light should only come on if the float comes close enough to the sensor