Jeep 5.2 V8 motors - Great Lakes 4x4. The largest offroad forum in the Midwest

Go Back   Great Lakes 4x4. The largest offroad forum in the Midwest > 4x4 Talk > Jeep Tech
GL4x4 Live! GL4x4 Casino

greatlakes4x4.com is the premier Great Lakes 4x4 Forum on the internet. Registered Users do not see the above ads.
Search
Reply
 
Thread Tools Search this Thread
Old November 5th, 2005, 09:21 PM   #1
Grandman
do i look old !
 
Grandman's Avatar
 
Join Date: 11-05-05
Location: West Branch Mi
Posts: 9,864
iTrader: (7)
Mentioned: 3 Post(s)
Default Jeep 5.2 V8 motors

Heres a little heads up im just ran into . I own a 94 Grand 5.2 , do to miles i tore down an extra motor i had to rebuild out of a 95 grand .

Well the heads up is the heads . Seems there very prone to cracking . This motor ran fine as does my current motor but once its tore down you find there is stress cracks between the valves . Given it is a design flaw its near impossible to find good used ones and the best price iv found on bare heads is $ 275.00 each .

Also these are roller cam engines , there the Magnum design and a rebuld kit will run you near $600.00 With out machine shop work or labor you looking at $1200.00 dollars in parts .

The good news is , the one i tore down still ran good and had 240,000 miles on it . They do last well .
Grandman is offline   Reply With Quote
Sponsored Links
Advertisement
 
Old November 5th, 2005, 10:33 PM   #2
GerkTJ
Senior Member
 
GerkTJ's Avatar
 
Join Date: 11-05-05
Location: ida, mi
Posts: 1,049
iTrader: (14)
Mentioned: 0 Post(s)
Default

so even with the cracks they are not leaking antifreeze into cylinders?
GerkTJ is offline   Reply With Quote
Old November 5th, 2005, 11:24 PM   #3
GreaseMonkey
Senior Member
 
GreaseMonkey's Avatar
 
Join Date: 11-04-05
Location: Madison Heights, MI
Posts: 18,003
iTrader: (22)
Mentioned: 1 Post(s)
Default

Check out www.manciniracing.com for any Mopar motor parts you might need. I've gotten quite a few stuff from them for the 440 BB I'm rebuilding.
GreaseMonkey is offline   Reply With Quote
Old November 5th, 2005, 11:27 PM   #4
Grandman
do i look old !
 
Grandman's Avatar
 
Join Date: 11-05-05
Location: West Branch Mi
Posts: 9,864
iTrader: (7)
Mentioned: 3 Post(s)
Default

Quote:
Originally Posted by GerkTJ
so even with the cracks they are not leaking antifreeze into cylinders?
Nope no leaks , but its like a time bomb so im not putting them on a new motor . My whole point is to reagain reliability .

Its not uncommon to have heads that dont leak but magnuflux them and find cracks .
Grandman is offline   Reply With Quote
Old November 5th, 2005, 11:31 PM   #5
PavementPounder
I am the law.
 
PavementPounder's Avatar
 
Join Date: 11-05-05
Location: Birmingham, Michigan 48009
Posts: 29,824
iTrader: (224)
Mentioned: 2 Post(s)
Default

Does the 360 from the 98 Limited use a different head? Might want to see if they are compatible.
PavementPounder is offline   Reply With Quote
Old November 5th, 2005, 11:55 PM   #6
h8pvmnt
Swamp Stomper
 
h8pvmnt's Avatar
 
Join Date: 11-05-05
Location: warren,mi.
Posts: 981
iTrader: (4)
Mentioned: 0 Post(s)
Default

Quote:
Originally Posted by PavementPounder
Does the 360 from the 98 Limited use a different head? Might want to see if they are compatible.
Naw magnum heads are magnum heads from what I understand. You can get heavy duty replacement style heads or the magnum r/t mopar performance heads, with hardened inserts instead of induction hardened seats, which prevents the cracking. A good site for small block stuff is :

www.hughesengines.com

They have a nice 420 c.i. small block for the 5.9's
h8pvmnt is offline   Reply With Quote
Old November 6th, 2005, 05:13 AM   #7
Grandman
do i look old !
 
Grandman's Avatar
 
Join Date: 11-05-05
Location: West Branch Mi
Posts: 9,864
iTrader: (7)
Mentioned: 3 Post(s)
Default

The thinkg that is causing the cracks is the new shape of the combustion chamber . The heart shape is causing a hot spot . Yes 5.2 or 5.9 either one is having the same issues .

Again there is options , theres just no cheap option on it .
Grandman is offline   Reply With Quote
Old November 6th, 2005, 07:51 AM   #8
5.9zj
Senior Member
 
5.9zj's Avatar
 
Join Date: 11-06-05
Location: Hartland
Posts: 285
iTrader: (2)
Mentioned: 0 Post(s)
Default

Quote:
Originally Posted by PavementPounder
Does the 360 from the 98 Limited use a different head? Might want to see if they are compatible.
nope same head as all 360. Even the dakota rt's have the same heads, even though some of those guys think they have the R/T heads. There are some expensive alternatives, mopar R/T heads and edelbrock aluminum heads.
5.9zj is offline   Reply With Quote
Old November 8th, 2005, 12:51 PM   #9
84Scrambler
Senior Member
 
Join Date: 11-07-05
Location: Lansing
Posts: 5,943
iTrader: (8)
Mentioned: 0 Post(s)
Send a message via AIM to 84Scrambler
Default

Yep, all 5.2 and 5.9 magnums have the same heads. I had the same cracks on my '96 5.2 heads. Both were cracked between the inner most cylinders. It is all too common with these motors. I have a set of 2.02 Mopar Magnum R/T heads sitting in the garage, but those are a little more than $275 a piece. ;)
84Scrambler is offline   Reply With Quote
Reply
Great Lakes 4x4. The largest offroad forum in the Midwest > 4x4 Talk > Jeep Tech

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -5. The time now is 03:35 AM.


Powered by: vBulletin, Copyright 2000 - 2012, Jelsoft Enterprises Ltd.
User Alert System provided by Advanced User Tagging (Lite) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd. Runs best on HiVelocity Hosting.
Page generated in 0.15241 seconds with 47 queries