Head gasket or cracked head?
#1
Newbie
Thread Starter
Join Date: Apr 2018
Posts: 28
Likes: 0
Received 0 Likes
on
0 Posts
Model: Cherokee(SJ)
Head gasket or cracked head?
so i replaced the thermostat and water pump on the jeep filled everything up let it cycle and Bubble and all that good stuff, I filled the resovor up as well. Now I have almost no coolant in the resovor two days after doing all this and what’s left in the resovor while the motor is running will bubble also when I’m coasting or sitting still the heat will get real cool until I get back on the gas. Is this more a cracked head or blown head gasket? No coolant in the oil and zero leaks
#3
CF Veteran
Join Date: Oct 2018
Location: United Kingdom
Posts: 1,576
Received 278 Likes
on
242 Posts
Year: 1995 RHD
Model: Cherokee (XJ)
Engine: 4.0l
Is there white smoke coming out of the exhaust (more than just exhaust fumes)? If not then from your description, water is not leaving the system which would not be a cracked head or gasket. Are you sure that the system is fully bled? The heater core could be trapping air.
Other than that, you may find fault in the pump or thermostat not letting enough coolant flow around.
The best way to actually test your theory though would be to use a leak down tester as that will indicate any cylinder pressure loss and where it's going. If water can get to the cylinders via the gasket or a crack, air will go the opposite way when testing and should show as bubbles in the radiator fill port.
Other than that, you may find fault in the pump or thermostat not letting enough coolant flow around.
The best way to actually test your theory though would be to use a leak down tester as that will indicate any cylinder pressure loss and where it's going. If water can get to the cylinders via the gasket or a crack, air will go the opposite way when testing and should show as bubbles in the radiator fill port.
#4
CF Veteran
Join Date: Nov 2017
Location: Groton, MA
Posts: 3,695
Received 234 Likes
on
207 Posts
Year: 1995
Model: Cherokee(XJ)
Engine: I6 4.0L
I'm going to guess that you probably just had some trapped air that has now worked it's way out of the system. Fill it up again and keep a close eye on it. It wouldn't hurt to do the leakdown test just to be certain, of course.
Thread
Thread Starter
Forum
Replies
Last Post
1998blackXJ
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
9
12-20-2014 02:42 PM
TABonifacio
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
27
02-06-2013 06:20 PM
DJKnightmare
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
20
11-14-2011 12:52 PM
Bigfinderman
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
10
10-13-2011 08:24 PM
Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)