1997 Explorer Sport 4.0SOHC w/135,000 miles / Problem areas

[MT native]

I just purchased a 97 Explorer sport with 4.0 SOHC for my daughter. It runs smooth but it has several minor issues. I just replaced the rack and pinion and both sway bar links and will move on to the brakes/rotors next. I knew the rack was bad when I bought it ( leaking out both boots that were destroyed) but I'm curious if there are any problem areas I should look at as I get this vehicle ready for my daughter to drive. I also replaced the on/off side of the cruise control switches as the tabs were broke under the horn pad and the switch was dangling. Issues I know of are: door chime on even with keys out, rear wiper doesn't work ( i can hear the relay tick when switch is on but motor won't work) , cig lighter short somewhere blowing fuse, froze up grease fitting on pass.side lower ball joint, temp guage not moving off L. Any suggestions or thoughts on what else to look at closely would be appreciated. Thank you...

 

[chefduane]

Considering you are in Montana... have you been able to see how it starts on cold mornings? Sometimes the upper and lower manifold gaskets can shrink over time and cause a vacuum leak making cold starts very difficult. Also, rough idle once started. That's certainly something I'd check.
Make sure that the heater and blend door operation is ok. Wouldn't want a defective heater in Butte!! Coldest recorded temp -48!! Yikes!!
On the temp gauge... night be the gauge itself, might be the sending unit, might be all that's fine and the thermostat is stuck open.
Good Luck! You're a good parent wanting to make sure your daughter has safe and reliable transportation.

 

[MT native]

Thanks for the reply! And yes, the heater does work great ( one of the first things I check besides having a block heater). I just bought the vehicle 3 days ago so I haven't run it in the cold yet, but is not throwing any codes such as lean condition on any banks to indicate shrunk or leaking intake gaskets. I will try change the water temp sensor and hopefully that is the fix for the guage not reading. Thanks again for the reply.

 

[koda2000]

Tip: You'll want to be careful trying to change the temp gauge's sender on a SOHC. It screws into the plastic thermostat housing (actually into a brass insert). Often the insert will break free of the plastic housing and you'll get a leak, requiring you to replace the housing (not an inexpensive or fun job). Later years had O-ring sender and sensor held in place with a clips.

Your thermostat may actually be the problem, even though you're getting heat. As you don't know when the t-stat was changed last I'd go ahead and change that first. You'll also need a new t-stat O-ring. I had the same issue with a 2000 Mountaineer V8. Gauge didn't move off cold but I got pretty good heat. The gauge doesn't really move until the water temp gets up to around 160+.

If you want to see if the sensor is at issue, I'd get a new one, attach the electrical connector and stick in a cup with 200 degree water and see if that makes the gauge read properly. It should be just under 1/2 way on the gauge.

 

[koda2000]

Regarding the rear wiper... Even when they "work" they don't work. I've given up trying to get working rear wipers. About the best you can achieve is 90% glass coverage (50% is more usual) and even with replacing motors, arms, blades, mounting grommets, rear glass switches and regular fiddling around it will always give you trouble. Not worth the time or money. My advice is to remove the rear wiper and forget about it.

 

[koda2000]

Re the chiming noise... Is it the key switch, or perhaps a door switch that's causing the chime? Does the Door Ajar light bulb work during the bulb check (key ON)? Is the Door Ajar light out when all the door are closed?

If it is the key switch, there's a switch inside the the ignition lock which may be stuck or broken. You can remove the steering column cover pieces (3-4 screws from underneath) to investigate. I believe it's a blue wire that is connected to the key lock cylinder switch.

Besides the brakes, which you are addressing, be sure to check the upper and lower ball joints and tie rod ends for play. To do this properly, jack each front wheel up just off the ground using the jack under the lower control arm. Check for ball joint play by wiggling the tire at 12 & 6 o'clock positions. There should be none. Check for tie-rod end play by wiggling the tire at the 3 & 9 o'clock positions.

It's very common for the SOHC engine (especially the older Job 1's) to develop starting and idling problems when cold do to intake manifold O-ring gasket leaks. The engine will typically run better once it warms up and during the summer months, but any vacuum leaks will cause similar problems (which don't improve once warm). The PCV grommet and elbow are common a point of vacuum leaks on the SOHC engine.

 

[manimal]

Regarding the rear wiper... Even when they "work" they don't work. I've given up trying to get working rear wipers. About the best you can achieve is 90% glass coverage (50% is more usual) and even with replacing motors, arms, blades, mounting grommets, rear glass switches and regular fiddling around it will always give you trouble. Not worth the time or money. My advice is to remove the rear wiper and forget about it.

How I resolved this issue in mine was to eliminate the mounting grommets and mount the motor directly to the inner door frame using nylon washers to replace the grommets. The grommets are there mostly to reduce audible noise from the motor, so far as I can tell, but they also allow the motor to move around enough to affect the tension on the wiper arm, resulting in uneven coverage of the wiper.

Once I made this mod, the wiper now covers 100% of its sweeping area, whereas before it didn't hold enough tension to get the upper and lower areas of the wiper arm sweep..


Ball joints.. When it comes to this it's easiest to replace the entire upper control arms, and replace only the ball joints in the lower control arms. This will take 1-2 days depending on how fast you work. I recently did this on mine and the ride is fantastic and tighter than my dad's 2000 with only 70k miles on it.

Most shops carry the UCA assemblies with pre-pressed ball joint and bushings - just unbolt the old ones, maintain the alignment cam positions in the mounts, install the new ones, and have the alignment checked - even though I maintained the UCA alignment, the toe still ended up being a little off after replacement.

My MIL lives in MT and I know you guys have plenty of nasty roads over there. Good ball joints are a must. When I gave her my 91 earlier this year, I made sure to replace all four ball joints in the TTB before I gave it to her.. They will get a workout in rural MT.