Flank
American by Birth, Texan by the grace of God.
Trying Draining and Filling. If a fail, then will try to mod.
Mod New Blue Hub Fan Clutch?
- Thread starter azlc77
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Trying Draining and Filling. If a fail, then will try to mod.
Flank
American by Birth, Texan by the grace of God.
Don't make it so hard on yourself.
Replaced mine last night. Did not have to do this. I got mine out without removing the battery, draining, shroud, etc. Just wiggled out of the left (facing toward rear of the truck, or passenger side). Got it back in the same way.
What you DO need to do is loosen your belts, as the nuts that hold the fan clutch on also hold the pulley behind it. Excellent time for new belts if you need them. (single kit of two side by side belts).
Replaced mine last night. Did not have to do this. I got mine out without removing the battery, draining, shroud, etc. Just wiggled out of the left (facing toward rear of the truck, or passenger side). Got it back in the same way.
What you DO need to do is loosen your belts, as the nuts that hold the fan clutch on also hold the pulley behind it. Excellent time for new belts if you need them. (single kit of two side by side belts).
Will second this. When the stock fluid started going bad in my "new" blue hub fan clutch, I started having trouble in the winter. 60-70 mph going up tahoe on a 40f day at full throttle and thing would heat up. I helped pull a truck up a hill at 7000 feet that couldn't get traction on the road, it was 25f out and the truck ran hot. At the low speed in cold weather using a lot of throttle it still needed the clutch. Frankly, I didn't believe it could be the clutch and my mechanic insisted that I start there, he was right.
Replaced the new blue fan clutch oil with 10,000CST by draining and re-filling with approx. 45ml. What I drained/recovered from the new OEM clutch was less then 30ml? With ambient temps of 93*F, I measured 60* F at the vents (idle) and 50* F (highway). Scangauge measured the WT (water temp) between 186*F, but not exceeding 188*F for a around town trip, including 30mins on the interstate (65-70mph). These measurements are all moderate improvements to the unmodified clutch, but are noticeable enough to be satisfied with new performance. The clutch is engaging more frequently, where as before (approx 2000mi on the new blue fan clutch) the clutch only, briefly, engaged on start-up, but was unnoticeable at any other time.
I did take the time to mod the the OEM eaton clutch with the same 10,000 CST and would be curious to see if it would out perform the newly modified blue fan clutch and/or would be more durable? I have read where others (toolrus, landtank) have opinions on the differences in designs of the external "fins" and internal mechanics, which may give the stock eaton a slight advantage. My only hesitation is that I have a new blue fan clutch with less mileage giving desrieable results, as opposed to a 117K eaton clutch that may or may not perform/last in comparison.... I guess it's all subjective. HTH
6 August 2010 / After a several days of 100*-105*F and high mid-west humidity in stop and go traffic I have decided to upgrade the 10K CST to 15K CST. Performance for the 10K is still as described above when temps are moderate, but add higher temps and performance decreases. My thinking is this- add 15K to help improve the higher temp days, but avoid any potential issues in the winter.
I did take the time to mod the the OEM eaton clutch with the same 10,000 CST and would be curious to see if it would out perform the newly modified blue fan clutch and/or would be more durable? I have read where others (toolrus, landtank) have opinions on the differences in designs of the external "fins" and internal mechanics, which may give the stock eaton a slight advantage. My only hesitation is that I have a new blue fan clutch with less mileage giving desrieable results, as opposed to a 117K eaton clutch that may or may not perform/last in comparison.... I guess it's all subjective. HTH
6 August 2010 / After a several days of 100*-105*F and high mid-west humidity in stop and go traffic I have decided to upgrade the 10K CST to 15K CST. Performance for the 10K is still as described above when temps are moderate, but add higher temps and performance decreases. My thinking is this- add 15K to help improve the higher temp days, but avoid any potential issues in the winter.
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I didn't alter the stock thermostat setting on my 97, but I don't feel that it's pulling enough air even with the 30k cst fluid so I'm going to pull it again and apply the LT calibration method.
My goal is to eliminate the swing of the RavenTai modded temp gauge above horizontal and to have colder AC duct temps in the heat of the summer.
The other car (96) has 10k and the LT calibrated clutch. Due to the variation in the candy thermometers' calibration, it may be set a bit on the cool side. It runs audibly most of the time when the AC is on, even at highway speeds in temperate weather; the AC blows cold though.
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My 1YO blue fan clutch is not engaging and the AC has luke warm performance at the 100F+ ambient temperature. I just picked up some 10k and 30k fluid and will probably have Randy put in the 30k fluid tomorrow.
inkpot
SILVER Star
Howdy! The big difference in the tear down time and effort is the Super Charger. It takes up alot of room around the front of the engine. It's even more fun when you also have dual batteries like mine. BTDT. John
If it's not engaging, you may want to adjust the clutch engagement thermostat IAW Land Tank's thread on how to set a blue hub fan clutch when you switch to 30k. While I am happy with the 30k in the 97 (now have 53*F AC duct temp even in 100*F heat), the clutch didn't engage well until I took it off a second time and adjusted it.
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Thanks for the tip. I'll have the clutch adjusted while it's apart.
There's no adjustment on an Eaton besides changing fluid is there?
I think you might have another problem if your ac is only getting down to 53 degrees. 2 cents MIke
Nope.
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Nope, not needed. If you check, monitor fan output temp, you will see that the factory setting is right in the fan need range. If it's adjusted down, the fan will run when not needed, wasting power. The fan runs when the fan output temp is high enough to demand it. If your not monitoring fan output temp it's hard to say when it's needed.
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It is overkill to try and keep the truck below 195f. You are aiming to keeping it below even a fully open thermostat. All you will do is waste a lot of gas. As long as the truck never goes over 220f, you shouldn't worry. I would suggest you read the old threads on this.
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X2 just about everything under the hood is designed to operate must efficiently at ~200F. The goal is to provide enough airflow so the coolers can maintain the devices they cool in the operating temp range, anything more than that is wasted power/efficiency.
Think of it this way: You could just remove the hood and have great airflow, then each time you stop it would cool off quick. But the motor operates best at ~200F, so a larger percentage of your starts will be cold starts, reducing efficiency and increasing wear. If you study the design of some of newer efficient cars, they have baffles/insulation to better hold the heat between drives for this reason. Enough cooling is good, excessive is a waste.
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I have another Eaton apart, checked the valve, first opening is ~120F and fully open at ~160F. Pretty much exactly matching the heat profile that I see for fan demand/need when monitoring fan output temp.
There may be a misunderstanding. My temp gauge was climbing close to the red arc on hot days when pulling up mild grades with the AC on. My goal was to eliminate this, and also to improve the AC function during all driving conditions, but particularly during low RPM operations. I realize that ~210*F is considered to be the most efficient temp for petrol internal combustion motors and am not attempting to keep it below 195*F.
Additionally, the gauge was modded ~4 years ago and I don't recall the ohm rating of the resistors used; the recipe has since changed so I'm not sure exactly what *F value lies at the center of my particular temp gauge.
If you look at the old thread, I believe 190 is right about the middle and 220f is the red. I know with my truck with the modded gauge, new radiator, new clutch, when it was 105f out, I would see 210-210f when pushing it to climb a hill on the freeway.
Your A/C performance may also be related to the A/C, charge, need for new evaporator, etc. To be frank, even when everything is working right, the A/C performance in my truck has never been stellar, and sitting in traffic is mediocre. You may be looking for performance out of the A/C that it can't give without putting in the middle east electric fan that goes in front of the radiator. Remember overseas the trucks also could be had with rear air to help A/C performance.
Thanks for the reply. After reading through RT's thread again, I realize that I need to de-sensitize my mk.1 eyeball gauge scanner more than I remembered being necessary. I was probably only seeing ~210*F when I was becoming concerned. The AC is now working about as well as I can expect from this R-134 system--I'm satisfied with that part.
We are used to not seeing gauges move anymore. Also, when there aren't numbers, you tend to start to worry. I know that I see the gauge go to 3/4 I start getting anxious, even though I objectively know it is fine. In some ways the scan-gauge is better because then you are just looking at the number. You see 210f on it and don't freak out.
