Just bought a 2002 XK8 and it smells like burning coolant. No white smoke.. No signs of leakage on the radiator. Smells like coolant is leaking somewhere and burning off.

Help!!!

 

My tiny leak is at the bottom of the thermostat housing. I've tried the cardboard gasket. I've tried the 0-ring gasket. I'm actually using them both at the moment. The leak doesn't want to stop and quite frankly it's leaking so little on my car that I've given up. Good luck finding and fixing yours.

 

Common problem is that the Norma connectors, located in the heater hoses above the catalytic converters on both sides will drip on the cat(s) and product the smell you describe.

Or the coolant reservoir will do the same thing and is also a common issue.

Best solution is to 'rent' a coolant system pressure test kit from one of the auto parts stores. Pump it up cold and you will know for sure where the leak is.

 

I agree with XENOPHOBE!!! I have a small leak somewhere and had my shop put on 2 housings but leak is very small that i got tired of tracking it down. My mechanic seems to think that cool to hot expansion in the hoses are the issue. Naaa, just him saying he has no clue either. I manage by topping off every month or so.

 

I agree with Test Point on the drip at rear of engine. I had the same problem, used my pressure tester to locate when the engine was cold. This tool has paid off over the years, I did have to purchase an adapter for the Jaguar.
One tip is to increase pressure slowly while checking since you don't want to convert a slow lead into a flood.

 

I have one also, and with four vehicles to maintain, it was a worthwhile investment.

 

Gee, for 'free' why not use the auto parts store's kit. With 21 fittings in the kit you would think there would be a Jaguar specific one . . . think again. Had to use the 'universal' adapter but it worked fine.

 

I experienced the same thing. Coolant smell after shut down. Turned out to be the coolant reservoir allowing seepage onto the exhaust manifold. In my case a very small amount (couple of drops), but enough to smell and will require replacement...on the to-do list

 

I wish my leak were easily fixable. The thermostat housing is just a bad design altogether. My cap was leaking. Got that fixed... still had the burning coolant smell... carefully retorqued the housing, is a minor leak at the base that doesn't want to go away.

That's not the real problem though, got a valve cover gasket starting to act up on the xk8.... *sigh*

 

I had the same problem with my 2001 XK8 for 2 years. The dealer said every thing was fine. I eventualy discovered the thermostat housing (made of plastic) had a hair line crack that expanded when hot. I replaced the housing with a new cast aluminum one no more smell but very difficult to get at to work on.

 

I have this problem with the cast aluminum one. There is no crack, but it doesn't want to not leak. Oh well. I have more pressing issues to correct.

 

I had to take the torque bolts out of the plastic thermostat housing, and replace them with bolts. This allowed me to torque it more. Stored the leak, then the cap leaked, put some thread tape on that. Worked for a day. Then leaked. Poured some stop leak in. (I know that is bad) but out stopped all but a couple of drops every so often. Thinking about bending some tin to get the drops to fall through rather than burning on the engine.

 

Advance Auto rental tool: Powerbuilt Coolant Pressure Tester Kit #70. The Orange adapter #5 (52mm x 3mm Threaded) is the correct fitting. It needs to be pushed in tight and snugged down, seating the O-Rings, before the threads can mate and pull it in tight. You can also get the adapter from Rockauto parts.

http://info.rockauto.com/getimage/ge...tant/12023.jpg

 

I posted this on a different thread but I also have the coolant smell on my 03 XK8 - seems there is a little drip from somewhere on the bottom of the expansion tank, dripping on the exhaust manifold. I am looking into replacing it but I need to check all the hose connections first.

 

One of the hoses from the heater bundle aka "the Octopus" runs directly up underneath the expansion tank. You can put your hand underneath to determine a leak at the connections. However, you first need to pressurize the cooling system, either buy driving the car, or attaching a coolant system pressure tester pump capable of reaching at least 13-16 psi. My cap, and the operational pressure, is rated at 1 Bar, which is 14,7 psi.


The connectors used there are of the 'spring clamp' variety. Often the older hoses are already compressed to the point wherein the spring clamp allows a drip. You can either get new hoses, which allow the re-use of spring clamps; or use 'screw-type' clamps on the existing [compressed] hose ends. I like the positive screw clamps vs the spiral screw designs. Either way, I usually put a screw clamp on first to ascertain whether or not that connection is the leak source. Remember, most leaks are found only under pressure.

 

Thanks, Gordo.....
I believe all the hose clamps are original, so I will check them first thing and at least put a better clamp on the offending hose (if it's not the expansion tank itself) for the short term. At 8 hot years and 89K, this cat's cooling system component inspection and some replacement might be wise, I think.

 

It makes sense to get to know this part of the car because eventually you are going to have some leaks back there. Get a head start and explore the water pump, water valve, the octopus, the two lines under the manifold, the front water pump, thermostat housing, and the expansion tank. I thought my leak was going to cost $200 in new rear hoses and it was fixed by a $1 clamp on the reservoir hard pipes.

 

Have a question on that... one of the nipples from the expansion tank is missing a line... one goes to the water pump assy up front, but I think there's supposed to be a line from that free nipple. Where to and is it important?

 

I looked at parts lists and system diagram... one is a bleed header hose (which I have) the other is listed as a bleed hose (missing).

 

One my '97 4.0 there are three 5/16" lines:

One to the T-stat housing;
the second to the driver side of the radiator,
and the third to the overflow tank behind the d/side wheel in the wheelwell compartment.