I hate to beat a dead horse but you might research the 4.56 application clutch. Just sayin...
CK5
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'89 R3500 Crew Cab 2wd to 4wd conversion & beyond
- Thread starter mrk5
- Start date
Started out with 2wd TBI350 with SM465 to current 4wd with 454, 700r4, NP241
More blades never hurts for what you are going after. You'll be moving more air at the same rpm because of it. Will it address the idle speed cooling? Maybe.
That's could be the last little bit you are going for. The severe duty clutch should do it so I don't see a need to change it.
That's could be the last little bit you are going for. The severe duty clutch should do it so I don't see a need to change it.
If you look at the Hayden clutch they list axle ratios, but it covers all of them. The only ones I found that listed axle ratio, said they worked for 3.73 and higher, or 3.42 and lower, so basically all ratios.
The aftermarket will always lump as much together as possible, I'm talking about GM stuff. This is why you'd likely find Rockauto or whomever listing the same "severe duty" clutch for a C10 350 as an ambulance but we all know GM spec'd those 2 applications very differently.
@ZooMad75 do you have access to dealer materials? If so, is there a different clutch for an '83 K30 dually w/ 454, 4spd & 4.56 gears?
@ZooMad75 do you have access to dealer materials? If so, is there a different clutch for an '83 K30 dually w/ 454, 4spd & 4.56 gears?
Another option but more costly is the Flex-A-Lite 6000 CFM fan. Any idea how much air the higher end clutch fans move?
Dual 15-inch S-Blade electric fan system with full shroud
Flex-a-lite® reversible S-Blade dual electric-fan system that moves 6,000 cfm of airflow with full shroud measuring 31 7/8 x 17 inches.
This fan puts the Windstar fan to shame.
Dual 15-inch S-Blade electric fan system with full shroud
Flex-a-lite® reversible S-Blade dual electric-fan system that moves 6,000 cfm of airflow with full shroud measuring 31 7/8 x 17 inches.
This fan puts the Windstar fan to shame.
The question I have is that every time you say it's running "hot" you say 200 or 210. That's not hot, I don't get worried until it passes 220.
210 is my threshold where I start worrying. It's not holding steady there, it's 210 and climbing. There was one point it hit 220. That's at the thermostat, so I figure the heads were a good 10 degrees higher. If it would hold at 210, I could deal with it. As soon as I get RPMs at 1500 or more the temps start dropping just as quick as they were rising. This is true in park or moving slow on the trail.
I also tried pulling timing out at idle and enriching the target AFR but neither of those helped.
I double checked the size of the fan I have now and it's 20". The opening in the shroud is 22". Derale recommends 3/4" clearance around the fan, so I couldn't go much larger than 20". I haven't found a fan with more than 6 blades that's standard rotation. So I don't think there's room to improve the fan I have now.
I also tried pulling timing out at idle and enriching the target AFR but neither of those helped.
I double checked the size of the fan I have now and it's 20". The opening in the shroud is 22". Derale recommends 3/4" clearance around the fan, so I couldn't go much larger than 20". I haven't found a fan with more than 6 blades that's standard rotation. So I don't think there's room to improve the fan I have now.
Maybe I need a different diameter water pump pulley.
GM used 7 blade fans on these trucks, I've got 2 if you need one.
Really? I would be yes.
After reading this https://www.flex-a-lite.com/blog/the-perfect-fan-shroud-position/, I'm thinking maybe I should play around with some spacers and see if I can get the fan pulled back out of the shroud.
The GM parts catalog goes back a ways but won't break down the difference between the clutches on 1983 trucks. There was a two letter code ink stamped on the cluch they refer too, but don't break it down.
So I bumped it up to 85 and looked again. 88891768 comes up for 6.2 &7.4, with and without heavy duty cooling, a/c and no a/c and auto trans with oil cooler.
There is a severe duty part number 19189703 that lists for only the 6.2.
I've read somewhere how much CFM mechanical fans pull and I think it was a very large number.
I don't know from experience, but I would do as you are thinking, and try spacers to pull the fan back out of the shroud some. I don't see a flange on the clutch for the fan to sit on, so it should be no big problem to try, just inconvenient.
I also really wonder if the fan clutch thermal spring is working properly. I heard that some guys have tried adjusting it by un-hooking the spring, and turning it one turn, then reinstall. I don't know which direction without using a heat gun to watch what the spring does, AND I have not tried this myself.
I wonder what you may discover about the clutch resistance by playing with a heat gun.
I also really wonder if the fan clutch thermal spring is working properly. I heard that some guys have tried adjusting it by un-hooking the spring, and turning it one turn, then reinstall. I don't know which direction without using a heat gun to watch what the spring does, AND I have not tried this myself.
I wonder what you may discover about the clutch resistance by playing with a heat gun.
Just throw it. With the upwind from that hurricane it might just make it
From my experience the biggest problem you have now is the fact your fan is completely in the shroud.
If you can't space it out simply enough it might be worth trimming the shroud.
You need at least an inch sticking out, otherwise the fan is blasting the wind inside the shroud and blocking the airflow instead of sucking it back. All the other stuff will be barely noticeable.
The reason you are overheating at idle only is because without moving air is not helping the flow through the radiator to overcome the pressure created by the fan in wrong place.
i know your working on options . but i know a few guys that have used this with AMAZING results in diesel applications .
https://www.evanscoolant.com/
zero psi in the cooling system / zero water / higher boil point / better heat transfer to liquid from metal .
https://www.evanscoolant.com/
zero psi in the cooling system / zero water / higher boil point / better heat transfer to liquid from metal .
I can hear it operating at the higher RPM. It comes on and goes off when I'd expect based on coolant temps.I don't know from experience, but I would do as you are thinking, and try spacers to pull the fan back out of the shroud some. I don't see a flange on the clutch for the fan to sit on, so it should be no big problem to try, just inconvenient.
I also really wonder if the fan clutch thermal spring is working properly. I heard that some guys have tried adjusting it by un-hooking the spring, and turning it one turn, then reinstall. I don't know which direction without using a heat gun to watch what the spring does, AND I have not tried this myself.
I wonder what you may discover about the clutch resistance by playing with a heat gun.
I put a straight edge on the shroud and the blades are pretty close to flush with the shroud. Which means I need to pull about an inch back.
I'm thinking I'll get the low profile clutch. Then space the fan off the clutch. Should get an inch there. Only thing I gotta watch is clearance to the alternator (the straight edge above is 1"). As @imiceman44 brought up, I may need to cut the shroud back too.
Getting the low profile clutch should also help rule out any possible issues with the clutch I have now.
Sounds good. Per the above I have some stuff to play around with in the meantime. Just let me know how much you for it.
I was a little skeptical about it making a difference but I read a thread on a hot rod forum about a guy having to do the same thing. He had cooler temps after moving the fan out of the shroud. So I'm more optimistic there's something to it.
I'm guessing a 6.2 water pump must sit about the same distance from the radiator as a 350. And a 454 shroud must be shallower.
I'm running coolant now that's supposed to be better than the average stuff. It may not be as good as the Evans tho.
Just take a body saw to the fan shroud, because you are to lazy to move the drive train back that inch.
I am really no help.
I am really no help.
Right now those both sound like a lot of work! 
