Clutch fan options on my 340?

-
71DodgeDemon340 said:
Just bought the 5 blade setup on ebay, thanks again rusty for the link, as long as the 5 blade is the same offset as my current 6 blade i should be good to go. Going to hold off on the new clutch for now until i get the fitment of the 5 blade fan confirmed, if its spaced the same in the shroud as my current 6 blade then i will order a new clutch
Click to expand...

That sounds like a plan.
 
72Dart6pack said:
I'm leaving this post. Good luck on your quest!
Click to expand...

I meant nothing personal, sir. I was simply making sure he knew the difference. The six blade fan is not the performance piece. It is simply a service replacement. This has been in the Mopar Engine Book for decades. Although it is dated, it is still extremely relevant. If you don't have one, I highly suggest it. It is well worth the money. Mancini usually has the engine and suspension books for ten dollars each. That's a steal.
 
I am not sure if this will work for you, but on my 74 Duster with factory AC (factory 26" rad and shroud) I used a 5 blade fan and clutch from an 88 Dodge pick up with a 318 and AC. It works very well and is readily available. Not sure how much HP it uses/

Cley
 
89 that is exactly what rusty and rumble were pointing me towards, the one i got of ebay stated it came off a 80’s dodge truck with a 318
 
Well the fan came in, ran the part number and seems to have came off a 89 dodge truck or ramchager. Fan looks to be in great shape, theres one little ding in the end of one of the blades, is this cause for concern?


698B6FE8-026D-4C0F-90E2-4237D9426D44.jpeg
81C3A936-B745-48F9-A56F-B381E0C18217.jpeg


I know im being to a certain extent a little anal about it but hey shouldnt i be lol.

So my existing setup was pulley, 1 inch spacer, than fixed 6 blade fan.

The 2947 clutch has about a one inch depth from where it bolts to the pulley to where the fan bolts to the clutch, so i took my fixed blade fan off, and leaving the one inch spacer on just held up the 5 blade since its nearly exactly where it will sit bolted up to the 2947 clutch. The blades were actually more centered in theshroud than my previous fan. Not by much but enough to notice.

Also double checked my measurements, the clutch should be right at a inch away from the radiator
 
Last edited:
Yup, that's it! What ding? LOL
 
Lol its more of a slight knick than a ding, nothing some fine sandpaper wont take care of.

One thing i noticed is how much lighter the 5 blade is compared to the 6, i wanna say the 6 blade weighs twice as much, that alone should help prolong water pump bearing life. Now just time to order the clutch......... and water pump........and thermostat lol

Edit: i just looked, i actually had a 7 blade fixed fan, # 46237

No wonder why the 5 is lighter lol
 
Last edited:
71DodgeDemon340 said:
Lol its more of a slight knick than a ding, nothing some fine sandpaper wont take care of.

One thing i noticed is how much lighter the 5 blade is compared to the 6, i wanna say the 6 blade weighs twice as much, that alone should help prolong water pump bearing life. Now just time to order the clutch......... and water pump........and thermostat lol

Edit: i just looked, i actually had a 7 blade fixed fan, # 46237

No wonder why the 5 is lighter lol
Click to expand...
I might have missed it, but does a higher blade count flow more air or visa-versa ? looks like a 6-7 blade would flow more, spinning the same rpm . ????
 
Do NOT get a non-thermal clutch fan.

Get the thermal one (with the spring on the front). They are the bees knees. First start up from cold you can hear them for ten seconds, then they kick in and the fan speed drops and they're quiet. I bought a Hayden one from Rock Auto.

The non-thermal ones quietly roar all the time, and that means you're using fuel and hp.
 
The clutch fan test is flawed. In the real world there would be heat from the rad and the clutch would be acting differently. No knocking the general results.
 
You must log in or register to reply here.
-

Back
Top