It seems a usual problem for all P2 cars... The upper big whole in the radiator cracks - where the whose from thermostat gets in. See the pictures:
Many VOLVO owners has replaced their GREAT GENUINE radiators with some said to be OEM ones, but after a couple k km the new radiators become to leak in the main alloy part. This way you got the decision to search for replacement from junk yard. It seems the genuine factory fitted radiators are great except this weak place - the connection pipe for the upper hose.
My friend did this repair before 5-6 mouths and he has no leaks yet. Mine radiator started to leak before a week or so and I knew that it's my turn so I bought the needed glue, take my tools and my photo and opened the hood.
What do you need:
A 7mm socket for the clamps. You may use screwdriver, but with the socket is easier.
Small hummer. This is to "advise" the new pipe to get all the way in.
A proper metal pipe. Alloy is best, so no rust gets there. 31mm outer diameter.
And the most important part here - the glue.
This is BISON EPOXY REPAIR AQUA. This thing is made to be water tight, resistant to chemicals and even sea water, with no problems in temperature differences. However it has to be applied in temperatures above 15 deg Celsius and dries for 24 hours. Meaning you got no car for day and a half and if it's cold outside you should do the job in the garage and keep it warm during the dry time.
Ok let's start with the pictures step-by-step part.
1. The problem:
2. The pipe. I used a pipe from old vacuum cleaner. There I had 4 different diameters, so I just had to choose which one is best for me
3. The glue. Bison epoxy repair AQUA. It's tested for exact the same repair - half a year with no leaks. If you've read some of my other repair manuals you know that after some periods I'll come back to this thread and give some info about this so that if anybody reads this after 2 years he'll be able to see that I've made this today and after a year it was/was not fine.
Here it is:
I've placed alot of it on the pipe.
Trust me, all the excess will remain outside, but you need to be sure you get as much of it between the alloy pipe and the broken radiator's pipe as you can. However do your best no glue falls into the radiator, because when it dries it become harder than stone and could cause clogging somewhere, or water pump damage!
And here it comes the advisor (errr hummer). With slight hits, using the side of the hummer help the alloy tube to get all the way in. In there is a hmmm something like stop/threshold where the inner diameter of the PVC radiator's pipe gets a bit lower - 29-30 mm. Mind that and do yourself measurements where that point is so that you could stop beating the alloy pipe just when it gets there.
Using mine thin walled pipe from old vacuum cleaner telescopic handle it become perfect. When I put my finger inside I'm almost unable to tell there the alloy pipe ends and where the PVC part of the radiator itself continues. I've tried to make pictures but ... they could be better. Sorry I really did my best for making better images.
And here you can see how I've removed all the excess glue and placed some back again with a lot of force just to ensure the water tight connection and to avoid any big differences in diameters so that no stress is applied to the hose after the clamp tight it.
My hose had some slight cracks, but was still fine. However I got another S80 for parting, so I took that hose from it. This is not of importance for this repair thou...
And Hey - You do this by your own risk and bla-bla-bla the usual understanding that I'm trying to help, but I'm not responsible for what you've done by your own
GOOD LUCK
p.s.
I believe it's not necessary to tell that first you need to drain the cooling system. For that procedure you need a 14mm socket to undo the PVC drain plug on the left bottom side of the radiator and to undo the green cap on the expansion tank so that no vacuum stops the cooling mixture to drain out. If you plan to reuse your cooling mixture (which I doubt) you should find proper tanks, but hey you've got a coolant loose - there is probably 99% clean water
However the cooling mixture is full with chemicals so think for the environment and drain it in tanks.Then on the next day when the glue has dried you should place back the hose, to tight the radiator's drain plug, to fill with coolant and do the air bubbles procedure (sorry for my English) However, I plan to fill with distilled water first, and after a week when I'm sure the repair was successful to drain the system again and fill it with coolant.
GOOD LUCK