First time buying a used engine. Advice? - JeepForum.com
Search  
Sign Up   Today's Posts
User: Pass: Remember?
Advertise Here
Jeep Home Jeep Forum Jeep Classifieds Jeep Registry JeepSpace Jeep Reviews Jeep Gallery Jeep Clubs Jeep Groups Jeep Videos Jeep Events Jeep Articles
Go Back JeepForum.com > Models > Jeep CJ Forum > First time buying a used engine. Advice?

Introducing MONSTALINER™ UV Permanent DIY Roll On Bed LineFS: 2007-2013 Jeep Wrangler "HALO" Angel Eye KitFS: Wranger BRIGHT License Plate LED! Just $3! Great value

Reply
Unread 07-01-2013, 10:41 PM   #1
TJ_T
Registered User
1984 CJ7 
 
Join Date: Sep 2012
Location: Portland, OR
Posts: 70
First time buying a used engine. Advice?

Hi,

I need to swap out the engine in my 84 CJ7. I've never bought a used engine and I'm curious as to any advice you have to offer regarding WHERE I should buy from and what I should look for.

I was told to test the compression but I don't have the equipment or know-how for that. Is it pretty straight-forward/cheap?

I'll take any advice really. Just need to be pointed in the right direction.

Thanks!

TJ_T is offline   Reply With Quote
Unread 07-02-2013, 12:39 AM   #2
KMD
Registered User
1976 CJ7 
 
Join Date: Apr 2009
Location: Modesto, California
Posts: 1,280
258? I would look for a 4.0 look for one still in the donor vehicle and ask to here it run. Compresion gauges do not cost a whole lot and are easy to use.

Any thing that has been hit in the rear and totaled is a good candidate for a decent running engine. Ask for service records.
__________________
Locked and Loaded 4x4 Club
KMD is offline   Reply With Quote
Unread 07-02-2013, 06:25 PM   #3
TJ_T
Registered User
1984 CJ7 
 
Join Date: Sep 2012
Location: Portland, OR
Posts: 70
Yeah 258. I'm just nervous that the next one I get will also have tons of blowby and issues.
TJ_T is offline   Reply With Quote
Unread 07-05-2013, 03:18 PM   #4
TJ_T
Registered User
1984 CJ7 
 
Join Date: Sep 2012
Location: Portland, OR
Posts: 70
So I'm trying to do a lot of research on what to look for and what I'm coming up with it:

-Compression test. Good compression is between 120-150 with no more that 30psi difference between the cylinders.
-Leakdown test. Not sure if I should continue to research this but it sounds a little more complicated.

As far as what to expect when buying an engine.. am I just looking for the block? I have recently installed a new water pump and starter. The carb I have is good. Should I just reuse everything I can off of my current engine?
TJ_T is offline   Reply With Quote
Unread 07-05-2013, 08:24 PM   #5
texasdave
Senior Member
 
texasdave's Avatar
1980 CJ7 
 
Join Date: Dec 2007
Location: Killeen, Texas
Posts: 793
You can get complete engines. You could get a short block which is just the lower side. You can get a long block which includes the head. You could rebuild your own that way you know what's in it. Unless you buy a complete engine you will need some of your parts from you old engine. External only.
texasdave is offline   Reply With Quote
Unread 07-05-2013, 08:32 PM   #6
MoC
Web Wheeler
 
MoC's Avatar
1986 CJ7 
 
Join Date: Jun 2008
Location: The otherside of your monitor...
Posts: 5,652
I have been burned on a used engine before. It was "running great before pulled." The description should have read "running great till the block cracked and was pulled."

Unless you can actually see it running I stay away.
MoC is offline   Reply With Quote
Unread 07-06-2013, 12:08 AM   #7
Skerr
Web Wheeler
 
Skerr's Avatar
1985 CJ7 
 
Join Date: Sep 2008
Location: White Springs, Florida
Posts: 8,761
Be advised... my 258 had 130 PSIs across the board, and I had so much blowby it was coming out of the dipstick tube. We are swapping in a 4.0, and although it would not be difficult for someone with experience, it is my first time and taking MUCH longer than I expected. It's my opinion, but pretty much any 258 you get is going to be used, unless you find a new rebuilt one, and I think that would be hard to find. If you have the time I would rebuild yours, or have a shop do it. I really don't know what it would cost, but someone else can give you an idea. That's the only way you will KNOW what is in it, unless you buy an altogether new motor.
__________________
Kerrdog
Go Fish! <*////><

"Contemplate the mangled bodies of your countrymen, and then say 'what should be the reward of such sacrifices?' ... If ye love wealth better than liberty, the tranquility of servitude than the animated contest of freedom, go from us in peace. We ask not your counsels or arms. Crouch down and lick the hands which feed you. May your chains sit lightly upon you, and may posterity forget that you were our countrymen!" —Samuel Adams

Clay's Build Thread
http://www.jeepforum.com/forum/f8/cl...hread-1061897/
Scott's Build Thread
http://www.jeepforum.com/forum/f8/sc...5-cj7-1147913/
Fallon (and Dad) Build Thread
http://www.jeepforum.com/forum/f11/f...-okee-1445206/
Skerr is offline   Reply With Quote
Unread 07-06-2013, 08:55 AM   #8
wellmax
Registered User
1984 CJ7 
 
Join Date: Nov 2008
Location: Hazel, KY
Posts: 1,046
I bought a long block from napa, for my 1984, a few years ago, it worked out fine, all the parts fit right on

runs good, its great checking the oil from time to time, no leaks and the oil mark is always full.
holds good oil pressure and motor starts and runs good.

when changing out a old motor, you need the other vehicle as there are many parts that you may need from the other vehicle, other than just the motor.
if its not exactly the same motor, word to the wise

even with the same motor/vehicle/model year/ they made production changes along the way and you will be surprised at the differences in how things may or may not fit.
wellmax is offline   Reply With Quote
Unread 07-06-2013, 09:23 AM   #9
Duso02
Registered User
1984 CJ7 
 
Join Date: Oct 2004
Location: Johnstown, PA
Posts: 7
rebuilt-jeep-engines.com

not a bad price and one hell of a warranty, 7yr/70K
Duso02 is offline   Reply With Quote
Unread 07-06-2013, 09:40 AM   #10
LumpyGrits
Registered User
1985 CJ7 
 
Join Date: Jul 2010
Location: The Mojave Desert Palmdale Ca. U.S.A.
Posts: 3,769
Have yours rebuilt.....
X2 on NAPA.
LG
LumpyGrits is offline   Reply With Quote
Unread 07-26-2013, 07:42 PM   #11
TJ_T
Registered User
1984 CJ7 
 
Join Date: Sep 2012
Location: Portland, OR
Posts: 70
I haven't had time to actually dig deeper but I'm fairly certain I threw a rod. A have a 5" gash in my oil pan caused from the inside. This would mean I wouldn't be able to rebuild the engine, right?

Leaning towards a new one. For the extra money spent.. the dependability and not having to worry about fixing further issues so close down the road in the way I would with a used engine... it almost seems worth it.
TJ_T is offline   Reply With Quote
Unread 07-26-2013, 09:04 PM   #12
titomars
Web Wheeler
 
titomars's Avatar
1981 CJ7 
 
Join Date: Aug 2009
Location: Santa Rosa, California
Posts: 1,744
Quote:
Originally Posted by TJ_T View Post
I haven't had time to actually dig deeper but I'm fairly certain I threw a rod. A have a 5" gash in my oil pan caused from the inside. This would mean I wouldn't be able to rebuild the engine, right?

Leaning towards a new one. For the extra money spent.. the dependability and not having to worry about fixing further issues so close down the road in the way I would with a used engine... it almost seems worth it.
That does sound like you threw a rod. As far as being non rebuildable that just depends on the damage inside. But with that being said it is an AMC 258 not exactly a rare engine. They are cheap and plentiful as cores. Since from your statement you do not even know how to check compression I would assume you are no engine mechanic. So my recommendation would be if you were to buy used only buy an engine you can hear run or drive it. Here in California any vehicle that runs is generally worth at a minimum of $1,000.00. A rebuilt long block is anywhere from $1,200.00 to 1,600.00. If I were you I would just buy a long block and transfer the externals and be done with it.
__________________
I don't worry about my MPG's. I see it as the price of admission...............Damn what a ride!!!
---------------------------------------------------------------------------
**Originally Posted by wm69 **
This is the kinda whiny crap I would expect to see in the JK forum. We drive rough riding, leaking, gas guzzling CJ's. Rattle can it and throw it in your Jeep.
---------------------------------------------------------------------------
1981 Jeep CJ7 258 4.0 HO head, T-5, D300, D30, D44, SOA
1994 Jeep XJ 4.0 HO, AX-15 (My Beater)
1946 Bantam T3-C (original Calif trailer, no rust)
titomars is offline   Reply With Quote
Unread 07-26-2013, 10:06 PM   #13
BagusJeep
Web Wheeler
 
BagusJeep's Avatar
1981 CJ7 
 
Join Date: Jul 2009
Location: Bali, Indonesia
Posts: 4,093
Oh, the joys of looking round scrapyards for an engine!!! I would not buy one unless I could see and hear it running or it was very cheap from someone I more or less trusted. I it is not on the starter you will not be able to measure compressions and if it is not running you will not hear the bearings or lifters.

Either way I always take them apart as they are out of the vehicle already and you can extend the life of the engine and improve compression with a little effort. Taking the head off and sump allow the checking of the bores, rings, pistons and bearings, which is straightforward, and I can have a go at the valve seats and put in a new head gasket and big end bolts. Honing an otherwise satisfactory bore and installing new rings and bearings would be high on my list to spend money on as well as replacing the rear seal and cleaning up the oil pump and pan. It is also a good time to look at the clutch and ring gear on the flywheel.

If I was really pedantic a real good clean with kerosene and a coat of AMC blue engine paint would make it look new.





The AMC258 is not a sophisticated design, it is very basic and hence easy to work on with the minimum of specialist tools. As a first engine to learn the skills on it is ideal.
__________________
BagusJeep lives in Bali, the Land of Temples.
With a Jeep every prayer counts.

1981 CJ7 258ci - Bagusjeep
1984 CJ7 258ci - Puthijeep
1981 J20 258ci - Gladys
BagusJeep is offline   Reply With Quote
Unread 07-29-2013, 12:20 PM   #14
TJ_T
Registered User
1984 CJ7 
 
Join Date: Sep 2012
Location: Portland, OR
Posts: 70
Thanks dudes. Really really leaning towards a new engine at this point and installing it myself is likely out of the question as I rarely have time to work on it and it's a little more than I'm interested in doing by myself.

Any guesses on how much it would take to make this happen with labor and all? One quote I got was about ~$3k.
TJ_T is offline   Reply With Quote
Unread 07-29-2013, 12:33 PM   #15
titomars
Web Wheeler
 
titomars's Avatar
1981 CJ7 
 
Join Date: Aug 2009
Location: Santa Rosa, California
Posts: 1,744
Quote:
Originally Posted by TJ_T View Post
Thanks dudes. Really really leaning towards a new engine at this point and installing it myself is likely out of the question as I rarely have time to work on it and it's a little more than I'm interested in doing by myself.

Any guesses on how much it would take to make this happen with labor and all? One quote I got was about ~$3k.
That's about right by my figuring. 12 to 14 hrs at $100. per = 1200.00 to 1400.00 in labor +parts.
__________________
I don't worry about my MPG's. I see it as the price of admission...............Damn what a ride!!!
---------------------------------------------------------------------------
**Originally Posted by wm69 **
This is the kinda whiny crap I would expect to see in the JK forum. We drive rough riding, leaking, gas guzzling CJ's. Rattle can it and throw it in your Jeep.
---------------------------------------------------------------------------
1981 Jeep CJ7 258 4.0 HO head, T-5, D300, D30, D44, SOA
1994 Jeep XJ 4.0 HO, AX-15 (My Beater)
1946 Bantam T3-C (original Calif trailer, no rust)
titomars is offline   Reply With Quote




Jeep, Wrangler, Cherokee, Grand Cherokee, and other models are copyrighted and trademarked to Jeep/Chrysler Corporation. JeepForum.com is not in any way associated with Jeep or the Chrysler Corp.