BIGISLANDHIKERS

My 89 laredo has 150,000. I am considering putting some $$ into the body. I am a bit hesitant because of the age. As a beginner are there things I should be looking for to assess the condition of the engine and transmission? Or is this something that a professional would need to do?

The Jeep was owned most of it's life by Michigan State University, so I am hoping it has been taken care of. It runs well, sounds a little like a diesel from the right side of the engine though. The oil pressure when cold is about 70. When it warms up it moves between 30 and 60 depending on the RPMs. While driving the temp hangs about 210 and moves up a tad when idling. Doesn't seem to be burning any oil and it doesn't smoke. The tranny fluid is pink and it shifts well. Not sure about the 4wd.

If I did take it in to a professional what would I ask them to do....Just look it over?


Thanks
BIH

OverlandZJ

Sounds like it's running well. The 4.0L's can run well into higher digits with proper maintenance.

Any oil on the air filter indicating blowby?

Running well and the body being solid i wouldnt hesitate spending a few $$ cleaning it up.

BIGISLANDHIKERS

Air filter area is clean and dry inside.

93gc40

By right side you mean the side with the spark plugs, correct????? I would check compression. If you mean the exhaust side I would be looking for an exhaust leak.

Dsandine

If it makes decent power and doesn't cough or hesitate I would say it is in good shape. You might want a compression test just to make sure that is all good. To check 4wd I would just engage it in 4 high (and drive pretty slow) and make sure the light comes on, if light doesn't illuminate could be bad bulb, either way I would engage it and do a very slow sharp turn to see if it bucks, I realize it is probably a bit hard on equipment but that way you know 4wd works, and I would do same procedure for 4wd low. You also might want to see if 4wd high engages on the fly. You could get injector's tested, but that might be a bit of an over kill, if it seems to be running fine I wouldn't waste the money there, and it would probably be a good idea to visually inspect spark plugs and look for signs of pre-ignition, vehicle running to rich, ect, and that is very easy to do. Also if you live in a cold climate I would check heat and make sure it works before I put any money into it because diagnosing and fixing heating problems can be expensive or if you do it yourself a huge pain in the neck. As far as the tranny as long as the fluid looks good when both hot and cold, and it shifts smoothly, I would say its most likely fine, and if your automatic has the power/comfort mode switch I would always run it in power, that way it doesn't slip as much when changing gears, and even in power mode the transmissions still shift very smooth. Like the guy who posted before said, if it sounds like a diesel from right side (I am guessing you mean if you are facing engine the right side where intake/exhaust manifold is) I would look for a leak in that gasket, and if it is leaking the gasket is a pretty simple job to do.

BIGISLANDHIKERS

Sounds like a diesel from the spark plug side(passenger side).

It has good heat.

BIGISLANDHIKERS

Never noticed before but I have what I guess is a lifter tick.

fishtaconc

The XJs have a factory installed valve train noise lol..... does it go away when the rpms increase?

TheJerm

I would not turn hard in 4x4 on pavement cause you will just be changing ujoint not too far in the furture. Go find a feild, ditch or even dirt road and you'll know right away if its in 4x4 or not. Although one problem with the 80's XJ is the vacuum disconnect in the front axle.

Do all fluid changes and check the clutch fan and t-stat. You dont want it running hotter than it should.

There's no way to adjust the lifter noise, unless you feel like take off the rockers and re-torqueing them to spec

I'm at 205K and drive the crap out mine everyday, just keep it cool and full of oil and it will run

razor02097

If you want to access the true condition of your Jeep there are a few things you can do at home. The following is by no means a complete analysis that can foresee or predict the life of a vehicle but will definitely access the vital functions of a vehicle and give a good indication the condition.

Check your gauges... is it charging around 14 volts? The oil pressure gauge working and not jumping all over? Does it warm up and maintain a water temp around 210'F?
Check exterior condition... is there anything hanging down or something broken or not plugged in that should be?

Borrow a compression gauge to check compression. You can usually find these at Autozone or some tool place, sometimes you can just use a loan-a-tool program. The engine may run right now but this test will tell you how well the valves and piston rings seal. Whether the engine will build enough compression to just run or if it has enough compression to run efficiently.

Next is to check for knocking or unusual noise. Most times the valve train will make a sewing machine sound at idle, this is normal. Slowly increase RPM from the throttle butterfly and listen for knocking or loud ticking.

Next is to check for blowby. Blowby is caused when the rings on the piston is worn the combustion cycle literally blows by the piston into the oil pan area. This pressure forces oil out the breathers into the intake. What you need to do is to take out the hoses and check or oil deposits. Some is okay but if your airbox is filling with oil then there is a problem.

The next thing may be a tad bit over the top but will tell you a LOT about the condition of the engine and trans. Take a sample of oil and trans fluid for analysis. a kit will probably run you less then 50 dollars. There are online resources that will tell you what the presence of all the different metals means.
http://www.oaitesting.com/prices_automotive_fleet.htm

Above all the easiest and quickest but least informative way is the butt dyno...

How reliable is the vehicle?
does it accelerate well and shift smooth?
will it go uphill without knocking?
does it stop in a reasonable distance?
will it round a corner without an out of control feeling?