Replacing Main and Rod Bearings in 4.0 XJ
#1
Newbie
Thread Starter
Join Date: Feb 2013
Location: Charlotte, NC
Posts: 18
Likes: 0
Received 0 Likes
on
0 Posts
Year: 1997
Model: Cherokee
Engine: 4.0
Replacing Main and Rod Bearings in 4.0 XJ
O.K., heres the deal. I'm tired of babying my Jeep around to keep the rattling rods from blowing a hole in the block.
Has anyone ever replaced only the mains and rod bearings in a 4.0 engine? I know, I'm supposed to turn the crank, but I have done this on farm tractors and road tractors (in-frame rebuilds) and they kept going for years.
Has anyone ever replaced only the mains and rod bearings in a 4.0 engine? I know, I'm supposed to turn the crank, but I have done this on farm tractors and road tractors (in-frame rebuilds) and they kept going for years.
#2
::CF Moderator::
Join Date: Aug 2011
Location: Prescott, Az
Posts: 43,867
Received 1,524 Likes
on
1,236 Posts
Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
Won't know til you see the bearings and crank.
How long has it been doing this?
How long has it been doing this?
#3
Newbie
Thread Starter
Join Date: Feb 2013
Location: Charlotte, NC
Posts: 18
Likes: 0
Received 0 Likes
on
0 Posts
Year: 1997
Model: Cherokee
Engine: 4.0
I've been driving it like this for a year. Has 40 psi oil pressure on start up. Drops to 10 psi after oil gets hot in about 5 miles. When the engine experiences no-load, like between shifts it gives off a very noticeable rattle. It's never given what I call a classic "rod-knock". Sounds like all the rods are rattling in unison.
I originally thought it might be the lifters, but an engine man said "its on it's way out", that is your bottom end.
I originally thought it might be the lifters, but an engine man said "its on it's way out", that is your bottom end.
#4
Newbie
Thread Starter
Join Date: Feb 2013
Location: Charlotte, NC
Posts: 18
Likes: 0
Received 0 Likes
on
0 Posts
Year: 1997
Model: Cherokee
Engine: 4.0
Where did my reply go?? Here it is again. I have been driving the Jeep like this for over a year. It has 40psi oil pressure on start up, drops to 10 when oil gets hot. When the engine is in no-load condition like between shifts it gives off a very noticeable rattle. It does not smoke or have what I called a rod-knock.
#5
CF Veteran
Join Date: Feb 2012
Location: central IN
Posts: 2,282
Likes: 0
Received 15 Likes
on
11 Posts
Year: 1997
Engine: 4.0
you sure it's not just spark knocking?
have you verified the oil pressure with a mechanical guage ? you won't get a years worth of driving out of a bad bearing (or 8). a friend of mine changed just the bearings in his jeep. it had low oil pressure and a noticeable tick at hot idle. no damage to the crank so he just replaced all the bearings with std size.
have you verified the oil pressure with a mechanical guage ? you won't get a years worth of driving out of a bad bearing (or 8). a friend of mine changed just the bearings in his jeep. it had low oil pressure and a noticeable tick at hot idle. no damage to the crank so he just replaced all the bearings with std size.
#6
::CF Moderator::
Join Date: Aug 2011
Location: Prescott, Az
Posts: 43,867
Received 1,524 Likes
on
1,236 Posts
Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
Where did my reply go?? Here it is again. I have been driving the Jeep like this for over a year. It has 40psi oil pressure on start up, drops to 10 when oil gets hot. When the engine is in no-load condition like between shifts it gives off a very noticeable rattle. It does not smoke or have what I called a rod-knock.
Auto trans? If so, flexplate bolts loose?
Thread
Thread Starter
Forum
Replies
Last Post
Blackcherokee290
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
27
07-26-2022 07:52 PM
lozo63
Stock Grand Cherokee Tech. All ZJ/WJ/WK Non-modified/stock questions go here!
3
08-27-2015 05:45 PM
EBowen95
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
49
08-25-2015 08:44 PM
thebyus
Modified XJ Cherokee Tech
3
08-25-2015 06:02 PM
Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)