HD fan clutch upgrade...

I just bought the Advance Auto Imperial brand one, turns out it is made in the USA by Hayden:patriot:! I only see about 0.1" (if that much) of added height front to back with the Hayden Imperial clutch. It's going in my 87 first thing in the morning. I will be posting temp data later. I did notice that if you install the OEM fan blade properly (ahummm) it moves the blade back towards the engine about 1/8 to 1/4" from the stock position.
 
I just installed the Hayden / Imperial clutch from Advanced Auto with no problems. Did not need to move the 1 row radiator to get it in. Mine is 87. Ran it for one minute, no extra noise that I could here, but then again mine has a noisy valve train already. I could feel an air flow improvement cold. Off for a trip now to test it.
 
When I did this install using the NAPA part, the new fan clutch was also a little wider making it too close to the radiator to easily install it. I have a two core all metal aftermarket radiator installed. To make room, I unbolted both engine mounts and jacked up the engine so it would pivot back about an inch to give me enough room to install the larger fan clutch. I've had it installed for about 5 months now and wheeled it with no interference with the radiator. It also seems to keep things a bit cooler out on the trail.

What year is yours?
 
Just ran into the same problem. I bought a TorqFlo #922737 from Autozone and it was around 1/4" longer than the stock clutch, plus the fan wouldn't mount flush with it.

I'm having the same trouble with my '98. I got the TorqFlo 922737 and the stock fan will not mount flush to the clutch unless I flip the fan over and mount it backwards. (Yes, I am sure that I am mounting it correctly.) There is plenty of room for the clutch, it's just that the fan doesn't mount flush.

I don't want to run the fan backwards so I guess my options are: to use washers to offset the fan so that it clears, to trim a little of the fan blade that touches the clutch, go back to stock clutch, or run the fan backwards. I will probably try washers first.
 
The clutch I bought came with washers for that.
 
Be-jessus it's hot today! 104.9 F, official South Houston temperature at 3:30 PM June 28th, a new all time record, and I think the sixth all time record day in a row here!

Just completed my new clutch upgrade tests. Got up to 239 F at the T-stat housing, 198 F at Radiator outlet with AC running (this a R-134a in an R-12 designed system, with a one row aluminum, 4 year old radiator), in some local stop (3 stops) and go trips, about 45 minutes. That is about a 40 F temp spread across the radiator, versus about a 30 to 33 F delta T before installing this clutch upgrade. So the new clutch is doing much better, well worth the $36. And this is about a 5 to 8 F hotter ambient temperature than my prior tests were.

Still way too hot for me at the T-stat with AC on, while still using a plastic Renix bottle.

Also, still not getting 100% reliable data at the dash gauge. Or maybe I am? But the dash gauge is not as responsive as the IR hand gauge reading at the T-stat housing, which gives me a true peak temperature and wider range. The dash gauge is slow to drop once the radiator coolant outlet temp drops back down, and slow to pick up on the higher outlet temp at the T stat, but it is more stable, does not jump around. It also reads about 20 F lower than the true coolant temperature. The sensor is only about 2 years old, and is reading the way it did when it was new. I just never saw it get this high before (actual temps), and thus never realized how biased, low reading, it was. It is off at least 10 F, if not 20 to 30 F based on my IR readings off the head near the gauge temp sensor. But the IR may be reading wrong, as the IR sees an area, and the exhaust manifold pipe, #6 is very close to that sensor, so I am not 100% sure of the accuracy of my readings back there. I do have a good feel what the IR and dash gauge should read at the same time now, so it is still useful for later comparisons.

Back to the new clutch, after the 3 stop trip, running the AC in 104.9 F temps, it was at 239 F at the T-stat, turned off the AC, and I let it run in park for about 20 minutes. Periodically ran the engine up to 2000, 1,500 rpm for about 20 seconds, in a water flow, air flow test, dash gauge reading test. The temps dropped back to 207-214 F (IR) at the T-stat housing, and 179 to 185 F (IR) at the radiator outlet / return side. While 180 F is nice with out AC, and 198 F is nice with AC, those temps are on the suction side of the water pump, and the 239 F (AC on) was on the pressure side of the water pump, so I must be getting very close to the 16 PSI boil over point with the plastic bottle/cap on the renix system. Also my R-134a high side pressure must be close to shut down on high pressure trip of the HP switch (400 psi, it was reading 345 psi the other day on a load test at about 93 F ambient).

I will be looking at a bigger surface area AC condenser (may look at the 92 and later XJ condensers that use R-134a!) and a 2 row all metal copper/brass radiator next, as I don't plan to push this beast around in 105 F weather with out AC, or with AC at 240 F :flame: coolant temps.

In summary, I love the new ZJ clutch upgrade, works great, but not good enough for 105 days like today if you plan to party in stop and no-go freeway traffic for long. It sure will help a new 2 row radiator give me more cooling.

My hats off to you guys for finding this COOL (LOL) little upgrade!
 
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I just installed the Hayden / Imperial clutch from Advanced Auto with no problems. Did not need to move the 1 row radiator to get it in. Mine is 87. Ran it for one minute, no extra noise that I could here, but then again mine has a noisy valve train already. I could feel an air flow improvement cold. Off for a trip now to test it.

I did finally hear the roar when I pushed it up to 3000 rpm, but I typically never get over 2400 rpm.
 
I see that the NAPA clutch is 0.15" taller from the spec sheets. Does anyone know about the autozone or advance brands, are the same, taller, or shorter than the stock FC?

Has anyone here done this upgrade on a renix jeep?

If so which radiator did you have, and what if any problems did you have installing it (clearance), or clearing the radiator?

I am starting to get the impression that the Renix radiators may be slightly closer to the stock clutch than the HO engines?

Are the shrouds different between Renix and HO?

And FYI, the fan mount height on the stock and HD NAPA clutches discussed here differ by .35" as well the overall 0.15" difference in overall clutch height.

I can barely install my stock clutch on my Renix with out moving the radiator off it's mounts on the top side (to lean it back enough to clear the studs) and I have a 1 row aluminum radiators.com radiator.

Mudderoy,

I have never had my jeep run hot here in Houston, not in 4 years, but the last few days have had me shivering as the system has peaked up to numbers like 235 F idle in the driveway at the thermo housing, in park with the AC on. It never got over 200 F before this week. I hear it hit 104 F here yesterday, 108 F heat index!

I've been running 210, or slightly less in the morning, and no higher than 215/216 on the way home at 5pm. Cloudy, or cooler 97, and it runs much closer to the 210, maybe 212/213.

jeephdfanclutch3.jpg


jeephdfanclutch4.jpg

NAPA 27310 on the left.
 
Was that with the AC on or off?
 
Was that with the AC on or off?

On. That's a good point. I need to test it with the A/C off. Before it would heat up going down the highway. If I turned off the A/C the coolant temp would drop 10+ degrees.
 
On. That's a good point. I need to test it with the A/C off. Before it would heat up going down the highway. If I turned off the A/C the coolant temp would drop 10+ degrees.


Where are you taking your temps, and what are you reading them with?

I am using an IR hand gauge. I have (had) 2 of them (different models), and I would some times get a 10 F difference between them, making me also question my test equipment. I think I trust the IR more than a thermocouple probe, as the fans blow too much air across the test surfaces I am checking and cool the probe too much while I am trying to get a reading. I trust bulk part radiation (IR) a little more (at least currently). My dash gauge says I am 190-200 F (rear head sensor) when my IR says the T-stat housing is at 225 to 235 F. I am sure I have no air trapped, so one of them is lying, or there is a huge differential between the coolant temps in the two locations on a Renix, and or one of the two temperature measurement devices are out of wack, or both.

My 87 and my 89, use to run cooler, 10 F cooler with the AC running (in say 85-90 F ambient, R-12 setup ), but the AC also turned on the electric fan. That was running with 160 and 180 T-stats.

This year with the R-134a upgrade (or downgrade), and the 100 F heat wave, it was, has been getting 20 F hotter when I turn on the AC, but I hot wired the fan a few weeks ago, so the comparison is a little bit different.

I suspect something in my valve train was out of wack (sticking lifter noise) for a long, long time, that made mine run cooler the last 4 years, as my daughters 89, with the new head, runs better, more power, but also about 20 F hotter than mine use to run. Now all of a sudden, my MPGs went up, and it started running hotter even with out the AC on. Now it runs a little hotter than my daughters, and hers started running cooler after her new head broke in. So many variables, makes it hard to isolate cause and effects. Also hard to figure out what really is normal with these beasts, and I have 4 of them!
 
Where are you taking your temps, and what are you reading them with?

I am using an IR hand gauge. I have (had) 2 of them (different models), and I would some times get a 10 F difference between them, making me also question my test equipment. I think I trust the IR more than a thermocouple probe, as the fans blow too much air across the test surfaces I am checking and cool the probe too much while I am trying to get a reading. I trust bulk part radiation (IR) a little more (at least currently). My dash gauge says I am 190-200 F (rear head sensor) when my IR says the T-stat housing is at 225 to 235 F. I am sure I have no air trapped, so one of them is lying, or there is a huge differential between the coolant temps in the two locations on a Renix, and or one of the two temperature measurement devices are out of wack, or both.

My 87 and my 89, use to run cooler, 10 F cooler with the AC running (in say 85-90 F ambient, R-12 setup ), but the AC also turned on the electric fan. That was running with 160 and 180 T-stats.

This year with the R-134a upgrade (or downgrade), and the 100 F heat wave, it was, has been getting 20 F hotter when I turn on the AC, but I hot wired the fan a few weeks ago, so the comparison is a little bit different.

I suspect something in my valve train was out of wack (sticking lifter noise) for a long, long time, that made mine run cooler the last 4 years, as my daughters 89, with the new head, runs better, more power, but also about 20 F hotter than mine use to run. Now all of a sudden, my MPGs went up, and it started running hotter even with out the AC on. Now it runs a little hotter than my daughters, and hers started running cooler after her new head broke in. So many variables, makes it hard to isolate cause and effects. Also hard to figure out what really is normal with these beasts, and I have 4 of them!

Yes there are so many external variables. I am only reading the OE gauge. I have checked the gauge with my Fluke IR probe and it is within 5 degrees of the gauge. I figured that was the difference between inside the thermostat housing and outside.

I need to wire up my efan to a override switch. I'm trying to come up with an overhead panel for a switch bank though first.

My MPG still sucks, about 12 to 13 mpg city.
 
I'm getting ready to read back in this post a little bit, but that damn clutch (or the fan spinning faster) makes a high pitch squeal at about 2800 rpm! WTH!?!?!

Like a belt squeal? The HD fan clutch stays locked until a little over 3000 RPM's, so it will be roaring like it would when you first take off after starting the motor until it gets to those RPM's. Should not be squealing though.
 
Like a belt squeal? The HD fan clutch stays locked until a little over 3000 RPM's, so it will be roaring like it would when you first take off after starting the motor until it gets to those RPM's. Should not be squealing though.

No, I'm all too familiar with the belt squeal. This is different. The squeal starts at 2800 rpm and stays there until the rpms drop below 2800. If I'm driving 70 mph on the freeway it squeals constantly.

I'm going to do a video today. I'll put the link up once I have uploaded it.

Yeah the NAPA guy told me they will roar, I told him this isn't a roar. The roar is there too, but this is a squeal. He says the roar will go away with use. He wasn't comprehending, or he's talked to one to many customers and now believes he knows better than them.

I started to take him outside and let him hear it first hand, but he already had that "deer in the headlights" look. :doh:
 
No, I'm all too familiar with the belt squeal. This is different. The squeal starts at 2800 rpm and stays there until the rpms drop below 2800. If I'm driving 70 mph on the freeway it squeals constantly.

I'm going to do a video today. I'll put the link up once I have uploaded it.

Yeah the NAPA guy told me they will roar, I told him this isn't a roar. The roar is there too, but this is a squeal. He says the roar will go away with use. He wasn't comprehending, or he's talked to one to many customers and now believes he knows better than them.

I started to take him outside and let him hear it first hand, but he already had that "deer in the headlights" look. :doh:

I had a similar issue after I installed a new water pump, radiator, & the HD fan clutch upgrade. This was only when I was running the A/C though. It turns out the brand new belt I bought was defective. I bought another belt and the problem has not come back at all. Not sure if this wil help you, but I thought I would throw it out there.

Definitely a great mod! My A/C still blows cool when I am sitting at a stop light or stuck in traffic.
 
My dash gauge says I am 190-200 F (rear head sensor) when my IR says the T-stat housing is at 225 to 235 F. I am sure I have no air trapped, so one of them is lying, or there is a huge differential between the coolant temps in the two locations on a Renix, and or one of the two temperature measurement devices are out of wack, or both.
When I did the 99 engine into my '91, I relocated the temperature gauge sender from the back of the head down to the block drain plug, and then drilled and tapped for another one in the thermostat housing. The gauge is consistently 15 degrees hotter than the computer in both locations. There are some real problems with these things. I am going to a junkyard and grabbing the OEM sensor and sender to test with, since I am a little worried at this point that maybe the Standard parts aren't up to snuff.
 
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When I did the 99 engine into my '91, I relocated the temperature gauge sender from the back of the head down to the block drain plug, and then drilled and tapped for another one in the thermostat housing. The gauge is consistently 15 degrees hotter than the computer in both locations. There are some real problems with these things. I am going to a junkyard and grabbing the OEM sensor and sender to test with, since I am a little worried at this point that maybe the Standard parts aren't up to snuff.

I remember some one here a year or 2 ago had a large difference between the after market gauge sensor (rear head Temp sensor) and the dealership sensor, both brand new. IIRC it was at least a 10%, like 20 F spread. Mine may have that very problem.

How are you getting the computer temp on a 91? Did you upgrade the PCM/ECU to 99 also?
 
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