Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here XJ (84-01)
All OEM related XJ specific tech. Examples, no start, general maintenance or anything that's stock.

Small bit of knocking on bottom end

Old Oct 23, 2015 | 02:27 PM
  #1  
DamonTaz's Avatar
Thread Starter
Newbie
 
Joined: Oct 2015
Posts: 10
Likes: 0
From: Alabama
Model: Cherokee
Engine: 2.8L
Default Small bit of knocking on bottom end

Hi. I just picked up a nice 86 XJ at a great price. It only has 180k miles on it. It's 2.8L 4x4. My question is this; after the engine warms up, there is a slight knocking on the bottom end, and that it was caused by the oil pump. What do you guys think? This is my 1st XJ and I got it because I couldn't pass on the deal, especially when it is as clean as it is. Thanks in advance.
Reply
Old Oct 23, 2015 | 03:24 PM
  #2  
Firestorm500's Avatar
CF Veteran
 
Joined: Apr 2009
Posts: 4,734
Likes: 12
Year: 2015, 2012
Model: Grand Cherokee (WK2)
Engine: 3.6L
Default

What kind of diagnostic procedures led you to believe and state that it was the oil pump?
Reply
Old Oct 23, 2015 | 03:28 PM
  #3  
DamonTaz's Avatar
Thread Starter
Newbie
 
Joined: Oct 2015
Posts: 10
Likes: 0
From: Alabama
Model: Cherokee
Engine: 2.8L
Default

I haven't yet. I just picked it up yesterday evening. It was told to me by the guy I bought it from.
Reply
Old Oct 23, 2015 | 07:08 PM
  #4  
Bustedback's Avatar
CF Veteran
 
Joined: Feb 2010
Posts: 12,367
Likes: 23
From: Oroville, CA
Year: 1995
Model: Grand Cherokee
Engine: 4.0 with all of the noise and clatter
Default

An oil pump won't fix the knock. Excessive bearing clearance is causing the knock. Good news and bad news. Bad news is that the 2.8 V6 is a turd of a motor sourced from GM, they're not a very strong engine and leak oil like crazy. Good news is that your XJ is a prime candidate for an engine swap. You can do a 4.3 V6 swap, a small block Chevy swap, an LS motor swap...
Reply
Old Oct 23, 2015 | 07:42 PM
  #5  
DamonTaz's Avatar
Thread Starter
Newbie
 
Joined: Oct 2015
Posts: 10
Likes: 0
From: Alabama
Model: Cherokee
Engine: 2.8L
Default

So, does that mean that engine is shot? How hard would that be to fix? Sorry if I sound l ignorant, but I've only tinkered with certain car motors, I'm expierenced in v-twin motors.
Reply
Old Oct 23, 2015 | 08:41 PM
  #6  
Hoosier8's Avatar
Seasoned Member
 
Joined: Jan 2014
Posts: 261
Likes: 1
From: Indianapolis, IN
Year: 1993
Model: Cherokee
Engine: 4.0
Default

Originally Posted by DamonTaz
So, does that mean that engine is shot? How hard would that be to fix? Sorry if I sound l ignorant, but I've only tinkered with certain car motors, I'm expierenced in v-twin motors.
Depends on the wear and if the crank needs to be turned. It means diss-assembly of the engine.
Reply
Old Oct 23, 2015 | 08:49 PM
  #7  
DamonTaz's Avatar
Thread Starter
Newbie
 
Joined: Oct 2015
Posts: 10
Likes: 0
From: Alabama
Model: Cherokee
Engine: 2.8L
Default

Alright. Thanks for all the help.
Reply
Old Oct 23, 2015 | 11:49 PM
  #8  
Firestorm500's Avatar
CF Veteran
 
Joined: Apr 2009
Posts: 4,734
Likes: 12
Year: 2015, 2012
Model: Grand Cherokee (WK2)
Engine: 3.6L
Default

Well, at least Chevrolet parts tend to be cheap and plentiful.
Reply
Old Oct 24, 2015 | 08:17 AM
  #9  
DamonTaz's Avatar
Thread Starter
Newbie
 
Joined: Oct 2015
Posts: 10
Likes: 0
From: Alabama
Model: Cherokee
Engine: 2.8L
Default

Yeah, that's true. Thanks for the info.
Reply
Old Oct 24, 2015 | 08:50 AM
  #10  
Bugout4x4's Avatar
CF Veteran
 
Joined: May 2015
Posts: 4,481
Likes: 18
From: Arizona
Year: 97
Model: Cherokee
Engine: 4.0
Default

If it is an Automatic it might be worth your time to check the Torque Convertor to Flexplate and Flexplate to Crank bolts before deciding the Engine is trashed. These can sound very similar when loose.
Reply
Old Oct 24, 2015 | 09:01 AM
  #11  
DamonTaz's Avatar
Thread Starter
Newbie
 
Joined: Oct 2015
Posts: 10
Likes: 0
From: Alabama
Model: Cherokee
Engine: 2.8L
Default

Thanks, I will check that out. It is an automatic.
Reply
Old Oct 24, 2015 | 09:15 AM
  #12  
Bugout4x4's Avatar
CF Veteran
 
Joined: May 2015
Posts: 4,481
Likes: 18
From: Arizona
Year: 97
Model: Cherokee
Engine: 4.0
Default

Originally Posted by DamonTaz
Thanks, I will check that out. It is an automatic.

This seems to be a common issue with these, Keeping my fingers crossed.
Reply
Old Oct 24, 2015 | 09:48 AM
  #13  
DamonTaz's Avatar
Thread Starter
Newbie
 
Joined: Oct 2015
Posts: 10
Likes: 0
From: Alabama
Model: Cherokee
Engine: 2.8L
Default

Thanks man.
Reply
Old Oct 27, 2015 | 06:02 PM
  #14  
DamonTaz's Avatar
Thread Starter
Newbie
 
Joined: Oct 2015
Posts: 10
Likes: 0
From: Alabama
Model: Cherokee
Engine: 2.8L
Default

So I'm under my jeep right now & was looking for an inspection plate to check the bolts as you have mention & is there not an inspection plate for an 86, bone stock 2.8 liter motor & tranny for this thing? If not, do I have to dump the transmission pan?
Reply
Old Oct 27, 2015 | 10:53 PM
  #15  
Firestorm500's Avatar
CF Veteran
 
Joined: Apr 2009
Posts: 4,734
Likes: 12
Year: 2015, 2012
Model: Grand Cherokee (WK2)
Engine: 3.6L
Default

"Dumping the pan" will only drain the fluid.

If you pull the starter, you might be able to see the bolts. There has to be a way to get to them.
Reply

Thread Tools
Search this Thread

All times are GMT -5. The time now is 05:33 AM.