Can't separate the fan from the fan housing

[Tommy Z]

Happy 4th All, I'm removing the dodgy alternator to take it for some bench testing buy I cannot separate the fan from the housing. Tried a little finesse but tapping on the bolts or the back side of the fan will not yield even a budge. Any suggestions on how to separate them? Any help is greatly appreciated.

[proporsche]

you have the wood-use gravity remove the fan together with the alternator by gently dropping it on the wood holding it with 2 hands.
After, same way hold the fan and gently drop it on the edge on wood..spray some wd40 on it

Ivan
maybe bigger piece of wood so it sit solid on the ground

[Synchro Joe]

https://www.pelicanparts.com/techarticles/911_alt_replace/911_alt_replace.htm

Not a fun task, and even some shops mess the process up. Tolerances are tight.

[Nditiz1]

What Ivan said as it works every time

[47silver]

Use a towel under it.
Use 4 2x4” in a square so that the edge of the housing will connect with the wood but not so far as to hot the fan. Raise assembly ?6” and drop fan flies out onto the towel.
I use a 6” plastic pipe or maybe a fitting (dont remember) to get the fan off of the alternator. Make sure edges of fan connect with the pipe tand drop alternator into the pipe. You can also use wood

[ErrorMargin]

Originally Posted by Tommy Z

Any suggestions on how to separate them?

Try this.

You can separate the fan from the alternator using the same procedure.

[mysocal911]

Originally Posted by Synchro Joe

https://www.pelicanparts.com/techarticles/911_alt_replace/911_alt_replace.htm

Not a fun task, and even some shops mess the process up. Tolerances are tight.

From the link;

Now, you can separate the fan/alternator from it's outer circular housing. Remove the screws that hold the alternator to the housing, and light tap on the studs with a hammer.

Total Mickey Mouse! In German, it's Metzger.

[Spetrow]

I don't like hitting the hitting the shaft due to impact loading of the bearings or bouncing and breaking a fan blade. This what i did this past week. I used a 6" schedule 40 PVC coupling (with stop) these can be found a most big box stores. 1. Cut coupling in half on one side of the stop. 2. Open up the stop by a small amount to clear the alternator body. 3. Glue the cutoff to the opposite side of the stop. 4. Press the shaft down. This process evenly loads the fan hub.

[john walker's workshop]

I did something similar for 964/993 alternator fan removal using a section of large diameter stainless pipe. Those fans Never want to come loose. The fan body OD is barely larger than the alt body, not much area to support.

[wazzz]

To separate the fan from the alternator, I used the puller technique.
I tapped two of the holes around the axle. I chose holes that are at 180 degree opposite ends. I used a 4mm tap. Holes were almost too big for this diameter, so I only used a one-pass tap.
Then I inserted two M4 bolts in those holes and tightened them little by little until they pressed on the alternator front face and gently pulled the fan from the axle. Very easy and no hammering.

[smadsen]

Yep, tap threads into two of the fifteen holes in the fan, 180 degrees opposite each other. Then orient the fan so the case of the alternator is under both threaded holes. Then turn two bolts, 1/4 turn each at a time against the alternator housing until the fan goes "ploink." Now you can remove the fan anytime w/o having to remove the whole assembly and drop it on something.

[ahh911]

Careful not to rub off too much magnesium when cleaning the fan housing for re-assembly. ( I wiped away some of the interference fit using scotchbrite, went a little too far).

Phil