1991 Briarwood bought 10min ago and already have issues

[Ecomike]

Depends on what other loads you strap on that alternator too? But by itself it might be OK. A good working fan clutch saves horsepower!!!! Keep that in mind.

Your problem is a classic bad fan clutch!!! If a new fan clutch does not solve the problem, an E-fan MOD would not solve it either.

A new fan clutch is only about $35. If you get the ZJ HD fan clutch they are tougher, and lock up sooner and turn the blade about 20% faster!!! I have Renix rigs with both the OEM and the ZJ (Grand Cherokee 4.0) fan clutch. Both work. I get a little better AC cooling at idle with the ZJ clutch.

So change the fan clutch. Then if it still overheats it is either the radiator needing cleaning or replacement or an exhaust leak blowing on the engine block. My last problem was a bad flange donut leaking exhaust on the block <1 " away from the block, and it even passed a muffler shop inspection!!!!

 

[SBpunk]

Depends on what other loads you strap on that alternator too? But by itself it might be OK. A good working fan clutch saves horsepower!!!! Keep that in mind.

Your problem is a classic bad fan clutch!!! If a new fan clutch does not solve the problem, an E-fan MOD would not solve it either.

A new fan clutch is only about $35. If you get the ZJ HD fan clutch they are tougher, and lock up sooner and turn the blade about 20% faster!!! I have Renix rigs with both the OEM and the ZJ (Grand Cherokee 4.0) fan clutch. Both work. I get a little better AC cooling at idle with the ZJ clutch.

So change the fan clutch. Then if it still overheats it is either the radiator needing cleaning or replacement or an exhaust leak blowing on the engine block. My last problem was a bad flange donut leaking exhaust on the block <1 " away from the block, and it even passed a muffler shop inspection!!!!

Ohhhhh I love junkyard mods. Ill have to look into the Zj fan clutch. It seems to be doing alright now. I havent got to really drive it since its still not completely legal (needs tires to pass safety) but I drive less than a mile to work and new ones are getting slapped on her today. ANYWAY Ill throw in a new fan clutch just because. It seems pretty easy to do but then again everything seems easy when people that have done it a million times tell you how to do it....

 

[djgrayxj]

Note from DJ
Joe Peters Fan clutch comparison:

Standard Fan Clutch:

• Turns fan 60-70% of shaft speed when engaged.
• Disengage to 20-30% of the shaft speed
• Used with lighter pitch fans. (1-1/2” of pitch).
• Flat plate impeller design with 11.4 Sq. In. of working surface.
• Identified by a smooth steel faceplate & thermal spring assembly on the front side.

Heavy-Duty fan clutch: ZJ HD fan clutch, NAPA #272310, direct fit upgrade, Not the Max Cooling--it won't fit

• Turns the fan 80-90% of the shaft speed when engaged for increased cooling.
• Turns the fan 20-30% of the shaft speed when disengaged.
• Used with deeper pitch fans. (2 -1/2” of pitch).
• Land and groove design with 26.0 Sq. In. of working area allows higher operating RPM’s.
• Identified by finned aluminum faceplate and thermal spring on the front.

If you use the HD fan clutch you will hear it when it is engaged unless you are deaf or have a really great sound system.

It is dollar for dollar the best upgrade to a stock XJ cooling system, IMHO.

 

[SBpunk]

Thanks for the heads up about the ZJ fan clutch. I had to order one from Alaska, have my parents pick it up and send it to me since I couldnt find a cross part number from NAPA to any other store. Of course none of the napa's on the island had it and they wanted to charge me 1/2 the cost to ship it out here.... garbage I can't wait to leave Hawaii.

Anyway the water pump seemed to work. I wish I couldve got a pic of the old one. The blades were gone. Not worn down but gone. The old lady is staying around 210 during idle and 190ish while its getting airflow. Under the hood still seems really hot but my last one did too. I'm dropping a THOR cowl intake in it once all my other parts get here to get some cooler air into the system. Still on the fence about hood vents just because hoods are easy to replace if I don't like them or if they are ineffective. Depends if I can find some Lebaron ones though.

 

[Ecomike]

TPS does not like water, just like Mugwamps, they turn into gremlins if they get wet, LOL. Hood vents tend to get them wet.

 

[Johnnie Walker]

TPS does not like water, just like Mugwamps, they turn into gremlins if they get wet, LOL. Hood vents tend to get them wet.

Unless you use drip trays or vents in a location as far away as you can.

 

[SBpunk]

I had planned on fabbing up some drip trays that dump the water onto the back of cowl and re run some of the electronics if they're too close. Anyway I probably wont do it since I dont like cutting into things unless I have to.

I do have another question and let me know if I need to make a new threat. My reverse lights and one tail light doesnt come on unless I shake the AW4 shifter. Is this a sensor problem or is it that my shifter is not sitting right in the tranny?

 

[Ecomike]

That is the NSS switch on the passenger side of the transmission for the back up lights. They can be opened up and cleaned, IF it comes off with out breaking it.

Tail light maybe another issue.

I do have another question and let me know if I need to make a new thread. My reverse lights and one tail light doesnt come on unless I shake the AW4 shifter. Is this a sensor problem or is it that my shifter is not sitting right in the tranny?

 

[SBpunk]

Yeah I'm going to go thru the wiring after I fail my safety inspection tomorrow. Get rid of this extra wiring since I dont plan on towing anything anytime soon.