Fan clutch

[Guest]

A month or two ago I had the fan clutch on my '77 Electra replaced with an OE type, thermodynamic? I think, not centrifugal. The car has a 403 Olds 4 barrell. Ever since the replacement, the clutch does not want to disengage with in-town driving. After a few minutes of highway driving, it does disengage and then has stayed quiet. The mechanic tells me it is acting as it should (stiff lubricant, needs breaking in, etc.) and should be better by summer! Does anyone else have any thoughts on this? Thanks for the help.

[Guest John Chapman]

I think you need a new mechanic with a better line of BS and another fan clutch, because this one is faulty.<P>JMC<BR>

[Guest]

Sorry to butt in here, but how does one replace the fan clutch w/o removing a ton of stuff??? I need a new one, but have no idea how to replace w/o removing everything.<P>Thanks & Happy Holidays!<P>-Scott<BR>

[NTX5467]

Until the "lock up" temperature is reached, the clutch will freewheel. On initial startup, it might be tighter until the fluid inside gets to where it needs to be, then it will freewheel or decouple. <P>Lockup temp typically is going to be above 190 degrees. With the cooler temps of this time of the year, possibly everything is operating as designed.<P>Even at highway speeds, it should not be locked up until the temp gets to about 210 degrees. If the undercar baffles are in place, there should be enough air flow from the vehicle speed to keep the clutch from needing to be locked up.<P>If you want something "stiffer", you can get in the Delco fan clutch catalog and check the dimensions for the clutch for your vehicle. Then match one of similar dimensions (especially shaft length and total depth) for a Chevy pickup application with the towing packages.<P>You can also check with a local dealer (with some older GM paper parts books) to get the original GM part number for the clutch that you can then cross in to the replacement number for AC-Delco clutches.<P>Centrifugal clutches lock up based on fan rpm levels. Thermostatic clutches (with the spring on the front) lock up depending on the temperature calibration of the spring independent of rpm.<P>Email me direct if you have any other questions.<P>Enjoy!

[Guest]

Scott, the fan shroud is about it. The hard part is getting to the fan bolts! The clutch is held it with the same bolts as the fan, so they are pretty tough to get to with the shroud on. Problem is you can't remove the shroud till the fan is off! Sometimes you can unbolt the shoud and lay it over the front of the motor with the fan now exposed it is a little easier. Don't losen any belts, you need them tight so the fan won't spin. good luck.<P>------------------<BR>buickfam@aol.com<BR>Life long Buick Fan.<BR>1965 Skylark H/T<BR>1965 Gran Sport Convertible<BR>1948 Chevy Pickup with 401 Buick.<BR>"Fan of anything that moves human beings"