Swapping heads, need advice
#1
Newbie
Thread Starter
Join Date: Aug 2014
Posts: 6
Likes: 0
Received 0 Likes
on
0 Posts
Model: Cherokee
Swapping heads, need advice
I own a 98 zj (4.0) and i have a rod knock but I want to swap my head with a 2000 WJ head its 4.0 as well. Will the bolt holes line up correctly? Or am I better off sending my head in to get rebuilt? Yes I pulled the VC off and the 3 rockers are lose (not crazy lose) no rods dropped. So I figure i better do something before it turns into an even bigger mess.
#3
Old fart with a wrench
The answer to your original question is yes, it will fit. See if you can score the intake manifold as well. It flows better than your old one.
#4
Newbie
Thread Starter
Join Date: Aug 2014
Posts: 6
Likes: 0
Received 0 Likes
on
0 Posts
Model: Cherokee
#5
Member
For me as I watched the video, sounded like the noise of a lifter. I wouldn't recommend to use any other oil viscosity than the factory, every parameter like oil pump flow, bearing clearance, and so on, is optimized to that, and it's not going to help, just mask the real problem.
#6
Old fart with a wrench
From the sounds of the video, that's just a normal 4.0! A thicker than normal oil will just make it louder. From what I've been told, the supply ports to the lifters are small and don't supply enough oil to the lifters at low rpms to maintain the valve lash closure. The noise usually disappears at about 1500 rpm or higher.
Valve rattle at idle is a known trait of the 4.0 and has been with us since it's introduction in AMC cars. I wouldn't worry about it unless it gets a LOT worse. If you stand next to a jeep that's idling, you can distinctly tell it's a 4.0 just from the sound. As a matter of fact. I would be worried if it DIDN'T make that noise.
So maybe you pulled the head for nothing.
Welcome to CF!
Valve rattle at idle is a known trait of the 4.0 and has been with us since it's introduction in AMC cars. I wouldn't worry about it unless it gets a LOT worse. If you stand next to a jeep that's idling, you can distinctly tell it's a 4.0 just from the sound. As a matter of fact. I would be worried if it DIDN'T make that noise.
So maybe you pulled the head for nothing.
Welcome to CF!
Last edited by dave1123; 08-29-2014 at 02:05 AM.
#7
Senior Member
Join Date: Jan 2012
Posts: 952
Likes: 0
Received 3 Likes
on
3 Posts
Year: 2004
Model: Grand Cherokee
Engine: 2000 4.0
From what I've been told, the supply ports to the lifters are small and don't supply enough oil to the lifters at low rpms to maintain the valve lash closure. The noise usually disappears at about 1500 rpm or higher.
Valve rattle at idle is a known trait of the 4.0 and has been with us since it's introduction in AMC cars. I wouldn't worry about it unless it gets a LOT worse. If you stand next to a jeep that's idling, you can distinctly tell it's a 4.0 just from the sound. As a matter of fact. I would be worried if it DIDN'T make that noise.
So maybe you pulled the head for nothing.
Welcome to CF!
Valve rattle at idle is a known trait of the 4.0 and has been with us since it's introduction in AMC cars. I wouldn't worry about it unless it gets a LOT worse. If you stand next to a jeep that's idling, you can distinctly tell it's a 4.0 just from the sound. As a matter of fact. I would be worried if it DIDN'T make that noise.
So maybe you pulled the head for nothing.
Welcome to CF!
The 4.0 is not a precise modern day engine and a little valve lash does not hurt anything. Us old timers that were around when most cars had solid lifters instead of hydraulic can tell you about NOISY engines!
Trending Topics
#8
Old fart with a wrench
Yeah, this engine started it's career in AMC cars in the late 60's and hasn't been changed much since, however it is incredibly reliable and long lived. The only thing they DO do is crack pistons occasionally. I think the reason for that is they are cast and not forged. Don't expect any modifications to increase horsepower. It's giving it's all now unless you want to decrease longevity.
#9
Whatever head you use, make sure to check for warpage before re-installing and use new head bolts. I have a brand new in the box set of FelPro ES71102 head bolts if you're interested.
Thread
Thread Starter
Forum
Replies
Last Post
jurazov
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
12
07-20-2023 04:13 AM
Travis88XJ
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
19
03-12-2016 07:26 AM
CherokeeHoonigan
Stock Grand Cherokee Tech. All ZJ/WJ/WK Non-modified/stock questions go here!
4
09-04-2015 12:47 PM
Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)