For anyone with a closed cooling system and a leaking coolant bottle, you may be able to replace it with one from a 240-series Volvo. There are other threads on this subject, but none really detail the (few) things you need to know about doing it. All of this pertains to findings made on an '89 Limited with the I6; YMMV.
Assuming that changing out the system for a closed-cooling type isn't an option, there are a couple of good reasons for going with this bottle vs. the stock one. Firstly, the Volvo bottles seem to be made considerably more durably than the OEM XJ bottle. They're also widely-available in junkyards and cheap: we paid somewhere in the region of $5 for it; not bad when you consider that finding a good coolant bottle for an XJ is next to impossible anywhere other than the dealer. The capacity's also about the same as the OEM unit, and it fits on the stock bottle mount with no trouble.
The bottle you're looking for can be found in early- to late-'80s Volvo 240s; the one we used came from a 245 sedan, gas, non-turbo. It's attached by one hex-head screw to a bracket against the passenger-side inner fender under the hood. Removal was dead simple: remove the hex screw and flip over the securing bracket, open up two hose clamps and remove the hoses and you're done. We got lucky and found one with a date of manufacture in 2002 stamped into it; be sure and check that the cap seals properly with the neck of the bottle.
Before you can fit it to the XJ, you'll need to adapt the top connector on the bottle to take the OEM XJ hose. We cut a length of (IIRC) 3/8" hose just long enough to cover the top connector, then slid it over it. It should be slightly difficult to get on; you want it to make a good seal around the connector. Some Vaseline on the inside of your adapting hose length should help. Note that the bottom connector shouldn't require any modification, but again, YMMV. It worked for us but I won't go so far as to say it will in all cases.
Remove the stock coolant bottle. Reconnect the Volvo bottle in its place, and use the securing strap to hold it back down; it should fit exactly where the OEM bottle went. Make sure that your hose clamps are good and tight against the bottle and refill with coolant as necessary. Drive around for a bit, adding coolant until the level remains constant. Check for leaks during this process.
After about 50 miles, the level seems to be staying where it should. Obviously we'll know more as time progresses, but for anyone else not wanting or able to convert to an open system this may be a workable alternative and certainly cheaper than the nearly $60 the dealer wants for an OEM bottle that'll probably rot out again.
Assuming that changing out the system for a closed-cooling type isn't an option, there are a couple of good reasons for going with this bottle vs. the stock one. Firstly, the Volvo bottles seem to be made considerably more durably than the OEM XJ bottle. They're also widely-available in junkyards and cheap: we paid somewhere in the region of $5 for it; not bad when you consider that finding a good coolant bottle for an XJ is next to impossible anywhere other than the dealer. The capacity's also about the same as the OEM unit, and it fits on the stock bottle mount with no trouble.
The bottle you're looking for can be found in early- to late-'80s Volvo 240s; the one we used came from a 245 sedan, gas, non-turbo. It's attached by one hex-head screw to a bracket against the passenger-side inner fender under the hood. Removal was dead simple: remove the hex screw and flip over the securing bracket, open up two hose clamps and remove the hoses and you're done. We got lucky and found one with a date of manufacture in 2002 stamped into it; be sure and check that the cap seals properly with the neck of the bottle.
Before you can fit it to the XJ, you'll need to adapt the top connector on the bottle to take the OEM XJ hose. We cut a length of (IIRC) 3/8" hose just long enough to cover the top connector, then slid it over it. It should be slightly difficult to get on; you want it to make a good seal around the connector. Some Vaseline on the inside of your adapting hose length should help. Note that the bottom connector shouldn't require any modification, but again, YMMV. It worked for us but I won't go so far as to say it will in all cases.
Remove the stock coolant bottle. Reconnect the Volvo bottle in its place, and use the securing strap to hold it back down; it should fit exactly where the OEM bottle went. Make sure that your hose clamps are good and tight against the bottle and refill with coolant as necessary. Drive around for a bit, adding coolant until the level remains constant. Check for leaks during this process.
After about 50 miles, the level seems to be staying where it should. Obviously we'll know more as time progresses, but for anyone else not wanting or able to convert to an open system this may be a workable alternative and certainly cheaper than the nearly $60 the dealer wants for an OEM bottle that'll probably rot out again.