Slow Coolant leak between bottom of coolant tank and hose Topic is solved

[lcc014]

In last oil change of my 1995 855 NA, I noticed that there were coolant leak (slow) out of the coolant hose under the coolant tank. I replaced the coolant hose (between tank and back side of engine). I drove the car last 2 days, and there are still have coolant around the end of the hose under the coolant tank. I tried to tighten the hose clamp as much as possible, but it still leak (slowly). The tank and hose were replaced together with Volvo parts 7 years ago. Now, with the new hose (also Volvo part), it still leak slowly.

Any idea what could cause the leak ? When I replaced the coolant hose, I did inspect the coolant tank, it looked fine to me, no crack.

Thanks,

Ching-Ho Cheng

[erikv11]

My guess would be a cracked tank. I know you looked for that but if you didn't notice anything, it almost has to be the tank at this point. Let's see if there are any good ideas from others.

[jreed]

I also have had to replace the tank due to cracks. How old is your tank? If it's original, and it's like the one in my car and the old yellowed ones I've seen in the junkyard, it's likely to have a crack.

[lcc014]

I also have had to replace the tank due to cracks. How old is your tank? If it's original, and it's like the one in my car and the old yellowed ones I've seen in the junkyard, it's likely to have a crack.

This tank is about 7 years old, not the original. Original had cracks so that I replaced it with this tank. Bottom of the tank is "dark/yellow". I could not see any cracks. The leak happened after car was driven (including waiting in front of traffic light, etc) for a while. In other words, leak happened under pressure and high temperature.

Thanks,

Ching-Ho Cheng

[hausmeister]

Check the small overflow nipple/hose. On mine the nipple on the reservoir was clogged, I used a drill bit to clean it. It had a few drips around that area sometimes, luckily I noticed this. worth a try to check this

[lcc014]

Check the small overflow nipple/hose. On mine the nipple on the reservoir was clogged, I used a drill bit to clean it. It had a few drips around that area sometimes, luckily I noticed this. worth a try to check this

The little hose is "new", less than 6 months old along with the new clamp. Here are some pictures of the area where the leak happens.

[scot850]

Is there a metal sleeve inside the lower hose outlet? It is meant to be there to prevent the plastic hose being squeezed so it is not round. If it is missing, then with that type of clamp it is not possible to get it to seal fully.

Also check it is not leaking from the level sensor.

If all that fails, then there has to be a small crack in the pipe where it meets the main header tank.

You could also see if you can get a different pipe clamp like those used on fuel hoses which clamp more consistently around a hose to prevent leaks.

Neil.

[kallekula]

Buy a new Volvo original tank

[lcc014]

Is there a metal sleeve inside the lower hose outlet? It is meant to be there to prevent the plastic hose being squeezed so it is not round. If it is missing, then with that type of clamp it is not possible to get it to seal fully.

Also check it is not leaking from the level sensor.

If all that fails, then there has to be a small crack in the pipe where it meets the main header tank.

You could also see if you can get a different pipe clamp like those used on fuel hoses which clamp more consistently around a hose to prevent leaks.

Neil.

Hi Neil,

Yes, there was a metal sleeve inside the hose outlet. I did not pay attention to it and to check whether it was still round or else.

When I replaced the hose, I did unplug the level sensor but did not remove it from the tank. AFAIK, there was no coolant residue around the level sensor area. I will try to find the fuel hose type clamp to try when the new tank arrive.

Thanks,

Ching-Ho Cheng

[lcc014]

Buy a new Volvo original tank

Yes, I ordered it yesterday from Boston Volvo.

Thanks,

Ching-Ho Cheng