Fan clutch test

[Grovebaby]

When cold engine, fan turns by hand with slight resistance. Fan spins when engine running. After reaching operating temp and stopping engine, fan turns by hand with slight resistance, maybe even a bit less than when cold. I expected it to turn harder after warmup. Is this fan clutch ok?

 

[93TwotoneXLT]

Sounds like the clutch is shot to me. I would definately recommend replacing the clutch. The fan is probably starting to crack around the base of the clutch too, so you might as well replace that while you are at it. You can replace both for around $100. Hope this helps.

 

[Grovebaby]

Oh yeah, the fan is seriously cracked, that's what led to the clutch investigation.

 

[Rhett]

Actually you can most likely run a long time with a cracked fan, I have seen lots of them on these trucks (almost all of them get the cracks) and I have never seen a fan fly apart yet. Of course, it's good preventative maintenance so I would go ahead and replace it if it were me. If the fan did come apart--that would be bad--and expensive.

Also at some point Ford moved to a fan with an extra blade, and they also improved the metal/plastic sandwich around the hub of the fan because of the cracking complaints...I think your 91 originally came with the early fan with (9?) blades. If you go to a dealer today, they will give you the newer fan. I don't think they even make the early fan any more.

 

[Jason94sport]

Also at some point Ford moved to a fan with an extra blade, and they also improved the metal/plastic sandwich around the hub of the fan because of the cracking complaint

Wow I didn't know that.
Dealer had a 9 or 10 blade fan in stock when I changed mine out. Since I had a 9 blade I replaced it with the same one.