NorCalChris
NAXJA Forum User
- Location
- Central Coast, Ca
Picked up a new rig yesterday. Finally made it back to my shop around 9:15pm tonight. Unloaded it off the trailer quick and fired it up. Did some quick performance tests and visual inspections.
Here is the pre-story:
Jeep was posted for sale here a few days ago. I picked it up Sat. Previous owner stated that it could have a blown engine, without diagnosing it, he couldnt be sure. He did say that it definetly had a drivability issue and lack of power. It is an 89 4dr XJ. 3 inch or so lift, rolling on 31 inch Falkens. Has a 29 spline 8.25, Logans winch bumper, all stock skids, and a handful of newer replaced components. Also, before he purchased the Jeep, it was in an accident of some kind, it is not a salvage title, but there is some minor damage where the bumper mounts too as well as some visible repairs.
Here is what I've done so far.
Checked all the fluids. No signs of anything except it needs an oil change.
Here is the pre-story:
Jeep was posted for sale here a few days ago. I picked it up Sat. Previous owner stated that it could have a blown engine, without diagnosing it, he couldnt be sure. He did say that it definetly had a drivability issue and lack of power. It is an 89 4dr XJ. 3 inch or so lift, rolling on 31 inch Falkens. Has a 29 spline 8.25, Logans winch bumper, all stock skids, and a handful of newer replaced components. Also, before he purchased the Jeep, it was in an accident of some kind, it is not a salvage title, but there is some minor damage where the bumper mounts too as well as some visible repairs.
Here is what I've done so far.
Checked all the fluids. No signs of anything except it needs an oil change.
Fired it up, it runs OK, not good, but ok. There is deffinetly an audible intake leak as well as a exhaust leak. Once it ran for a few mins I drove it around the shop a few times. Never once heard a mechanical problem with the motor. Once it was warm I did what I like to call a durability test. (Also works well on freeing up stuck lifters and/or exhaust valves in the 4.0) Reved it up in stages til I got to 4k rpm and held it there for five minutes. If it is going to grenade it will do it during that test hopefully. Ran fine without a hicup. Brought it down in steps back down to idle. It has a very low idle( under 500rpm).
After that I noticed that the temp was slightly above 210, not near the red, but still above 210. The cooling system is showing signs that we either have: an airflow issue, coolant level issue, or both. Could be other items as well obviously, but those are where I believe it is. All my Xjs have had idle temps right at or below 210, even trail temps around 210, so this system is deffinetly showing its efficincy level. I let it sit for a few minutes idling, the temps did not drop (with the fran clutch engaged). I then turned the heater on to realize that warm air was not wanting to come out, verified that the blend door was indeed moving.(I should note that there is no heater control valve installed on this vehicle at the moment). After letting it run for a few more mins slightly warm air had begun to show. Signs that there is either an air pocket in the heating system, or a plugged up heater core.
After that I noticed that the temp was slightly above 210, not near the red, but still above 210. The cooling system is showing signs that we either have: an airflow issue, coolant level issue, or both. Could be other items as well obviously, but those are where I believe it is. All my Xjs have had idle temps right at or below 210, even trail temps around 210, so this system is deffinetly showing its efficincy level. I let it sit for a few minutes idling, the temps did not drop (with the fran clutch engaged). I then turned the heater on to realize that warm air was not wanting to come out, verified that the blend door was indeed moving.(I should note that there is no heater control valve installed on this vehicle at the moment). After letting it run for a few more mins slightly warm air had begun to show. Signs that there is either an air pocket in the heating system, or a plugged up heater core.
After all that I noticed that the charging volts (on the gauge)was just over 12volts. All accesories off it should be reading closer to 14. Something else that must be addresed. I shut the Jeep off and visually inspected the engine compartment. Valve cover leak, zj fan clutch, newer looking water pump as well as clean rtv around the tstat housing, upgraded headlight wiring harness as well as a working and cold blowing A/C system =}
So here is what is next. I'm going to compression test the engine and go from there. If a leakdown test is needed that will be next. A full tuneup is needed, replace the TPS, clean TB and IAC... If the head has to come off then this is the perfect opportunity to throw on one of my 7120 heads port matched to Renix manifolds, I have to replace the intake/exhaust manifold gasket, so I might as well swap the head. Also, the injectors are going to be replaced with Ford 19lb injectors. Gen III's FTW!
That is all for tonight, hopefully sometime this week I will have more time to look at it. Here is some pics for your entertainment.
