Gents,

Attached photos show a coolant leak I discovered after adding dye to the system. I'm not sure but I think its my head gasket. The oil shows no signs of contamination, neither does the coolant. The leak is very small and is finding its way down the right/passenger side of the transmission.

Please comment on whether it may be something else or time for a new head gasket.

Thanks in advance,

David

 

On the back of the head there is a 'cylinder head rear cover'.


I would get a mirror and a light and check around there. Much easier fix than new head gasket.

Jag has a TB for this as well that says use Bar's Leaks. Interesting, most people avoid coolant stop leak like the plague, Jaguar said it should be in every engine. Who knows what they say about it now...

Cylinder Head Gasket - Coolant Seepage - Add Bar's Leaks
MODEL
88 MY-Onwards Sedans

DATE
3/92

ISSUE:
Coolant seeping from the cylinder head gasket edge.
ACTION:
Determine if the head gasket seal is seeping or leaking using the following guidelines:
Seeping - Side of engine block is stained with coolant and/or liquid coolant collects along the edge of the head gasket. One or two drops of coolant may fall on the floor overnight.
Leaking - Coolant streams from the head gasket edge. Puddle of coolant forms on the floor overnight.
If the head gasket is seeping, allow the engine to cool and perform the following operation:
^Remove header tank filler cap slowly. Crush the tablets of two packages of Bar's Leaks (JAG 138) and add them to the coolant header tank. Replace filler cap.
^Clean the engine surfaces so that any new coolant seeping can be detected during the next scheduled service visit.

Do not replace the head gasket for seeping unless Bar's Leaks was added during the previous service visit and seeping is still evident.
If head gasket is leaking, replace gasket and add Bar's Leaks.
NOTE:
Bar's Leaks must be added whenever engine coolant is changed. Refer to Technical Bulletin 27-7.

PARTS INFORMATION:
Part Number Description Qty.
JAG 138 39 Gram package Bar's Leaks 2

 

gunnerman,

Thanks for the info.. I love this forum. Of course, the question that popped into my head was; can I change a gasket at this location?

Also, looking forward to any comments on whether Bar's Leaks is good/not good.

Cheers!

 

I'm not sure if you can change it out in the car. I've always had the head off doing a head gasket and changed that rear gasket. From what I remember it is a different gasket that was a thin plastic film with a small bead of silicon added to it. If you can get all the bolts out then carefully scrape it off and glue the new one to the cover and remount. There's not a lot of room back there so............

 

Update!

It appears as though the Bar's Leaks worked for now. I'll keep the forum posted. Thanks for the info on the gasket replacement. I'll try to avoid that if possible.

I have a friend who is a 20 year-plus master Cadillac technician. He said some Cadillac engines had the same issue and Bar's Leak fixed that as well. One tip he gave me was to add only half the bottle, then drive for about 5 miles and then add the rest (this from his vast experience).

I guess I'm going to have to find time to read all the other TSB's out there...

Thanks again.

Cheers! No more leaks!