Hello everyone,

I am new to the forums, but a long time lurker. I have just had a recent problem with my 1996 850(5) Wagon GLT with 181k. So here's what happened. I ended up breaking the nipple off of the radiator (circled in picture(ignore the dipstick writing)), the car overheated and coolant was everywhere. I ended up being able to make a swedge with a piece of metal with the same diameter to put the broken threads of the nipple flush with where it broke off. I used epoxy to create the bond. Its holding on very strong and I think may be even stronger than the original piece was. But here's my question, I try to run coolant through the system, but after the car warms up enough for the coolant to be needed, the coolant reservoir overflows. I leave the cap off to see when the flow starts, and I've left it off during the process. Is pressure like this supposed to occur? Should I try to run coolant through it with the cap on? I've heard from a friend that the only time he's seen the coolant reservoir overflow like this, is when there's a more serious problem, like a blown head gasket. Can anyone shed some light on this? Thanks.

 

If youwere able to repair the broken nipple you will be the very first person I have ever encountered that could do it. I've tried many times and I have never had long term success. I'm rooting for you.

From your picture I see that you have the gray colored overflow cap. Whatever the chemical makeup of that plastic was didn't work and they all crack. Volvo superseded that cap with another one that is a greenish color and it won't crack and it will seal well forever. The part is only $5.00 at FCP so it can't be much worse than that at the stealership. I would start by changing the cap.

...Lee

 

Welcome to the forum.

What is the coolant level in the reservoir when the engine is stone cold? Manuals state that you fill up to the MAX mark when the engine is cold, which turned out wrong as far as my 850 was concerned. If filled up to full, coolant was overflowing from the cap so I filled only up to somewhere between MAX & MIN. Never had overflowing problem after that. Also, the reservoir itself is known to go south in some cases. I replaced mine with a new reservoir.

If the head gasket is shot, you would notice drop in the coolant level as it enters into the combustion chamber and exit the tail pipe as white smoke with coolant odor. You would have also noticed some loss of power, so I believe the head gasket is fine.

Does this help?


JPN

 

Both of these posts were completely helpful. I'll come back to let you guys know what's going on. Thanks!

 

Yes, definitely replace that gray cap. It is as sure to leak as is the power steering cap on the P2 model XC-70's