I'm at the end of my rope.....
Coolant keeps disappearing. 200ml every week. There are NO external leaks. Checked everywhere including heater core. Compression is very good and strong across the board. Pressure test is good. The coolant does not appear to be contaminated in any way. I do have some mayonnaise in the dipstick but it gets cold up here. Condensation? . I replaced the rad cap.
no white smoke, good performance.
WTF...maybe a cracked head that does not affect combustion or a bad head gasket? The car was overheated once about 5 years and 75k ago.

Any ideas would be appreciated.
Txs
Jocoman

 

Lift the coolant bottle up and off its bracket to get to the underside where there is a pipe from the bottom of the tank make sure this is tight as leaks from under here are very difficult to spot when looking around in the engine bay - Mike

 

Thanks for the suggestion, but its all dry under there.
Jim

 

do you get any condensation on the windsheild? my 98 had a mystery leak that actually turned out to be the heater core leaking into the floor padding. the tip off was the condensation. -just a suggestion.

a cracked head and a bad gasket will show up as compression loss if it's at the block deck. look for coolant in the oil. you really shouldn't have any -mayonnaise??. a compression leakdown test is the preferred way to check if you haven't already.

good luck

 

What did you come up with for the loss ??


If you haven't found it yet you can also try a cooling system UV dye. You add it to the coolant and then check it with a black light. It might be that it's leaking someplace where it's evaporating as quickly as it seeps ??

With the dye you'd see the residue of any leakage.

 

I put dye in the system about a month ago. Two weeks ago I pulled the plugs and number one plug was green. (colour of the dye). So...it has been parked ever since and I started the head gasket replacement last night.
I was really hoping it wasn't the gasket, but oh well.
On a more positive note, I just picked up a 1997 850 awd turbo wagon with 99000 km on the clock. It is one sweet ride. So I have a vehicle to get around with and i can take my time with the head gasket repair.
Txs everyone.
Regards