What to do coolant leak… (1 Viewer)

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.

Joined
Mar 21, 2016
Threads
10
Messages
154
Location
Okinawa City, Japan
Hi all!
1993 KZJ78 with 1KZ-TE leaking coolant somewhere. Servicing the overflow almost every two weeks to “full” line. Took it to a Land Cruiser Mechanic and had him see if it was an external leak before calling it a bad gasket. He performed a pressure bleed down check, radiator and associated hose damage checks, heater core and lines check and no leaks noticed. No white smoke, no over temp on gauge, no discolored oil or coolant or coolant smell inside. Pulled the head last week and according to the Mechanic, “No problems with the head gasket as far as I can visually see. The cylinder head was also checked and no serious cracks were found.

However, this engine may have cracks in the water jacket that are not visible.
“Suggestions we can make are as follows

1. replace the head gasket and see how it progresses.

2. send the cylinder head for inspection and replace it accordingly.

3. replace the cylinder head without inspection.”
I would like to ask if just replacing the gasket and pressing on would be a good idea or would having it inspected and replaced, if actually cracked, be better? If the gasket was not torn but just old, is it a safe assumption that it was allowing coolant to leak out slightly enough to just show on the reservoir? Anyone have experience with this? Thank you for your advice!!
 
I wouldn't put it back together until the leak is found and fixed. 1KZs are (in)famous for cracking heads. Usual places to crack are valve seat to valve seat, or valve seat to pre-combustion chamber. I would assume your mechanic would have found these. Have the valves been taken out? It's also possible for heads to crack up behind the valves (i.e. in the intake or exhaust ports). A crack leaking straight into the exhaust could go unnoticed.

At the other end of the scale, have simple things like radiator cap and expansion (overflow) tank been checked?
 
I wouldn't put it back together until the leak is found and fixed. 1KZs are (in)famous for cracking heads. Usual places to crack are valve seat to valve seat, or valve seat to pre-combustion chamber. I would assume your mechanic would have found these. Have the valves been taken out? It's also possible for heads to crack up behind the valves (i.e. in the intake or exhaust ports). A crack leaking straight into the exhaust could go unnoticed.

At the other end of the scale, have simple things like radiator cap and expansion (overflow) tank been checked?
I 100% agree. I am having the head pressure tested. No, no reservoir cracks/leaks and radiator cap was recently replaced with brand new along with water pump and timing belt.
 

Users who are viewing this thread

Back
Top Bottom