TheAMCForum.com Homepage
Forum Home Forum Home > The Garage > AMC V8 Engine Repair and Modifications
  New Posts New Posts RSS Feed - Newbie here needs advice on recent purchase
  FAQ FAQ  Forum Search   Events   Register Register  Login Login

Click for TheAMCForum Rules / Click for PDF version of Forum Rules
Your donations help keep this valuable resource free and growing. Thank you.

Newbie here needs advice on recent purchase
 Post Reply Post Reply Page  12>
Author
Message
  Topic Search Topic Search  Topic Options Topic Options
FREDMAXX View Drop Down
AMC Fan
AMC Fan


Joined: Jan/20/2019
Location: Fort Worth, TX
Status: Offline
Points: 6 		Post Options Post Options   Thanks (0) Thanks(0)   Quote FREDMAXX Quote  Post ReplyReply Direct Link To This Post Topic: Newbie here needs advice on recent purchase
    Posted: Feb/01/2019 at 7:08am
Hello all. Newbie here. I recently purchased a 1982 Wagoneer Limited with 160K miles. The previous owner had started replacing a corroded out water pump/timing chain cover. The front of the Wagoneer is disassembled (grill, radiator, fan etc.). Before I started reassembling it, I checked the compression. Two of the cylinders are at 100 while the others are between 135-150. Long story short, I’m afraid the motor is tired. I really want to “restore” the rig back to a running/driving vehicle to enjoy. So my question is, do you suggest removing the present motor and rebuilding it or buying another motor to swap in? Current configuration is a 360 with a 727 tranny and it is 4 wheel drive (not sure if there are any 2 wheel drives). Any serious advice would b greatly appreciated. Thanks - Fred

Edited by FREDMAXX - Apr/18/2019 at 10:31am
Back to Top
Trader View Drop Down
AMC Addicted
AMC Addicted


Joined: May/15/2018
Location: Ontario
Status: Offline
Points: 6881 		Post Options Post Options   Thanks (0) Thanks(0)   Quote Trader Quote  Post ReplyReply Direct Link To This Post Posted: Feb/01/2019 at 7:17am
Rebuilding an old running motor is usually always better then pickup up an unknown motor.
A 360 rebuild is not that bad if your looking at a stockish rebuild. 
Back to Top
FREDMAXX View Drop Down
AMC Fan
AMC Fan


Joined: Jan/20/2019
Location: Fort Worth, TX
Status: Offline
Points: 6 		Post Options Post Options   Thanks (0) Thanks(0)   Quote FREDMAXX Quote  Post ReplyReply Direct Link To This Post Posted: Feb/01/2019 at 7:20am
Thanks for the prompt response. I was going to post a photo, but I haven’t quite got this figured out yet.
Back to Top
NCSteve View Drop Down
Supporter of TheAMCForum
Supporter of TheAMCForum
Avatar

Joined: Nov/25/2017
Location: North Carolina
Status: Offline
Points: 70 		Post Options Post Options   Thanks (0) Thanks(0)   Quote NCSteve Quote  Post ReplyReply Direct Link To This Post Posted: Feb/01/2019 at 8:54am
I agree with Trader, rebuild the current motor. I did one for my YJ back in 06. Went .20 over, new rings, bearings, crank cleaned up, water pump housing, oil pump, water pump, heads cleaned up and checked, ss bolt kit, mild RV cam,  performer intake and D.U.I. distributor. I would keep stock exhaust manifolds too. No leaks, exhaust modifications or performance loss for my application in my opinion.  Although the it ended up later on in a Chief and has moved on, it is still running great today.
1970 Big Bad orange AMX, 390 4speed, Go Pac
1979 Jeep Cherokee, 360, 4 speed/D20
2015 JKU Rubicon Tank Green
Back to Top
White70JavelinSST View Drop Down
Supporter of TheAMCForum
Supporter of TheAMCForum
Avatar

Joined: Aug/08/2012
Location: Minnesota
Status: Offline
Points: 4866 		Post Options Post Options   Thanks (0) Thanks(0)   Quote White70JavelinSST Quote  Post ReplyReply Direct Link To This Post Posted: Feb/01/2019 at 8:56am
FREDMAXX,

You'll need 30 posts on this forum before you have permission to post photos, place adds, and other stuff.

Question for you, did you squirt a little WD40 or similar into the cylinders before doing the compression tests? The compression may come up. Could be gummed up rings or valves not seating properly. A compression test will not show you what's leaking, just that something is leaking. Do a leak down test to get a better idea of where the leakage is.

BTW 100 psi isn't terrible for a low, I've tested engines with cylinders as low as 80 psi and others at 130 and they still ran OK.

If you do decide to rebuild the 360, try to find a shop that understands it's an AMC engine and not a small block chevy.  There are a few nuances (like main bearing clearances that aren't like the SBC) that when SBC shops put together an AMC it causes trouble.  The aftermarket cam sprocket is another area that will cause trouble if not handled correctly. Whatever you do, don't go to Richard Rawlings...LOL
Seriously there's a ton of good information about engine rebuilds on this forum. just heed my advice and find the correct AMC oriented shop for the build.


Edited by White70JavelinSST - Feb/04/2019 at 10:52am
70 Javelin SST, second owner, purchased 1972
Back to Top
wheelz View Drop Down
AMC Apprentice
AMC Apprentice


Joined: Jan/29/2019
Location: NJ
Status: Offline
Points: 101 		Post Options Post Options   Thanks (0) Thanks(0)   Quote wheelz Quote  Post ReplyReply Direct Link To This Post Posted: Feb/01/2019 at 9:11am
I hate to admit but an LS swap makes more sense in a FS Jeep. Lots have been done

http://fsjnetwork.com/forum/viewtopic.php?t=767
Back to Top
6PakBee View Drop Down
Supporter of TheAMCForum
Supporter of TheAMCForum
Avatar
Charter Member

Joined: Jul/01/2007
Location: North Dakota
Status: Offline
Points: 5457 		Post Options Post Options   Thanks (0) Thanks(0)   Quote 6PakBee Quote  Post ReplyReply Direct Link To This Post Posted: Feb/01/2019 at 9:16am
Originally posted by FREDMAXX FREDMAXX wrote:

So my question is, do you suggest removing the present motor and rebuilding it or buying another motor to swap in?


I'd go for door #3.  Put the motor back together as is, run it for a while, then take a compression check and make a decision where to go.  I'd never trust a compression check on a motor that has been sitting for a while.
Roger Gazur
1969 'B' Scheme SC/Rambler
1970 RWB 4-spd Machine
1970 Sonic Silver auto AMX

All project cars.

Forum Cockroach
Back to Top
AMXRWB View Drop Down
AMC Addicted
AMC Addicted
Avatar

Joined: Apr/25/2013
Location: Midwest
Status: Offline
Points: 1153 		Post Options Post Options   Thanks (0) Thanks(0)   Quote AMXRWB Quote  Post ReplyReply Direct Link To This Post Posted: Feb/01/2019 at 10:02am
I would put it together and drive it first.Then you can see if you like and enjoy the truck.You also may have other unknown driveline problems that you will not find until you drive the truck.
Back to Top
pacerman View Drop Down
Supporter of TheAMCForum
Supporter of TheAMCForum


Joined: Jul/03/2007
Location: United States
Status: Offline
Points: 9057 		Post Options Post Options   Thanks (0) Thanks(0)   Quote pacerman Quote  Post ReplyReply Direct Link To This Post Posted: Feb/01/2019 at 1:25pm
Originally posted by 6PakBee 6PakBee wrote:

Originally posted by FREDMAXX FREDMAXX wrote:

So my question is, do you suggest removing the present motor and rebuilding it or buying another motor to swap in?


I'd go for door #3.  Put the motor back together as is, run it for a while, then take a compression check and make a decision where to go.  I'd never trust a compression check on a motor that has been sitting for a while.

I agree with the above.  Do a differential compression check as well as a cranking compression check too.    You may find the the engine only needs a valve job and has many miles of life left in it otherwise.  Joe
Happiness is making something out of nothing.
Back to Top
Greyhounds_AMX View Drop Down
AMC Addicted
AMC Addicted
Avatar

Joined: Nov/14/2009
Location: Kansas City
Status: Offline
Points: 1268 		Post Options Post Options   Thanks (0) Thanks(0)   Quote Greyhounds_AMX Quote  Post ReplyReply Direct Link To This Post Posted: Feb/01/2019 at 1:44pm
Try the low cylinder again with a squirt of oil down it to see if it changes. 
1968 AMX 390 w/T5
Back to Top
 Post Reply Post Reply Page  12>
  Share Topic   

Forum Jump Forum Permissions View Drop Down

Forum Software by Web Wiz Forums® version 12.03
Copyright ©2001-2019 Web Wiz Ltd.

This page was generated in 0.156 seconds.
All content of this site Copyright © 2018 TheAMCForum unless otherwise noted, all rights reserved.
PROBLEMS LOGGING IN or REGISTERING:
If you have problems logging in or registering, then please contact a Moderator or