Vacuum pump tool to pull stuck rotary vane

[zillah]

Dear Experts

Is there any specific tool to pull a vacuum pump stuck rotary vane (fan)

https://imgur.com/a/Pnu7PAS

Yes, I did remove the circlip that is attached to the shaft

Thanks

[Gyro]

A three legged puller is probably the normal method, thers's always the danger of fracturing the fan though.

Your best bet is probably differential expansion - get the alloy fan nice and hot and it should expand more than the shaft and allow you to pull it off. Refit the same way, hammering will damage the bearings.


P.S. Make sure there aren't any burrs on the shaft from removing the circlip - you don't want to get it stuck half way!

[coppercone2]

bearing puller, heat and maybe oil?

if it sticks out with the shaft, you can basically make a reinforcement by drilling out a wood circle with a hole saw, drilling a hole in the middle, cutting it in half, assembling it under the fan, screwing it together, then using the bearing puller on that.

I had this problem on a tile saw, I ended up hamming the fuck out of it and just replacing the fucked up bearings, they were kinda old anyway. they are pretty cheap and it will help things run smooth..

[KL27x]

P.S. Make sure there aren't any burrs on the shaft from removing the circlip - you don't want to get it stuck half way!

I'mma go one further.

I've removed a circlip with tweezers, then spent a good 10 minutes trying to get the bearing off. The burr I put on there was where the bearing didn't even start, at all, let alone get halfway off. I had to put it under the microscope to see it and stone it away. Then the bearing slid off with just finger pressure.

[tpowell1830]

The vaned rotor appears to be made from plastic, I would not heat that. Also, it makes it problematic to use a puller, but I would try it out and see if it does not create too much stress on the vane to the point of distortion. With that said, a little force and gentle tapping may make it move. Do not get too agressive with that vaned rotor. The other option, since you have some room behind the rotor is to make a couple of wedges to slide behind the vaned rotor and gently tap them in for assistance.

Sometimes, these can get very stubborn, but if that rotor is plastic, you must be patient and gentle.

Hope this helps...

[zillah]

Thanks guys for your help

The vaned rotor appears to be made from plastic,

Yes it is from plastic

[Gyro]

Damn, I didn't look at the third photo - yes it's plastic with the alloy looking paint flaking off. 

Presumably the circlip is to retain it. The shaft has a flat on it to stop the fan spinning freely.

In that case, your best bet is probably a couple of levers between the motor housing and the fan - but push them downwards so they act on the inner hub of the fan, not the edge. A couple of long screwdrivers might do it, otherwise you'll need to fabricate a couple of bars that bend up at the end.

[zillah]

yes it's plastic with the alloy looking paint flaking off.

Yes as it is not a quality vacuum

[coppercone2]

you can still heat it a bit with a hot air gun, it might be safer actually if the plastic gets a bit less stiff so it won't crack on you. You might deform it though.

I think the rule of thumb is to keep it under 70C.

[Gregg]

I would try the following:
1.    Brush away the paint where the shaft and fan meet with a fine wire brush
2.   Make sure there are no burrs from the snap ring groove
3.   Warm up the plastic fan; heat will cause the plastic to expand more than the steel of the shaft making the fit a little less tight (hopefully)
4.   Put some thin oil on the joint but be sure not to use a penetrating containing a solvent that would harm the plastic. 
5.   Use an adjustable wrench with nice flat surfaces that won’t damage the shaft to fit on the flat part and keep the shaft from turning as you gently try to twist the warmed plastic fan by hand; the object is to allow some oil to penetrate the junction between the fan and shaft and to fracture any paint that may have penetrated.
6.   If you can get two prying levers under the fan so that they are against the shaft and use compressive force directly on the hub from below rather than bending forces on the plastic, it may work.  You may have to rotate the prying position all around the fan several times to get it off.

[zillah]

Thanks guys for your help and insights

[tpowell1830]

Thanks guys for your help and insights

Don't forget to update us on how this went.

[zillah]

Don't forget to update us on how this went.

Will try all your suggestions and techniques with care and see how it goes and update you
Regards

[Ian.M]

Caution: many plastics have poor compatibility with mineral oils - depending on the plastic, they may cause it to swell or make it brittle and far more likely to crack.   Neither would be good for your chances of removing that impeller without damage.   I would be extremely cautious about using any lubricant to aid removal.

[donkey77]

I second gyro's method. I normally use two of the biggest flat screwdrivers I have, one each side. Sometimes there is two knockouts in the plastic mould that you can use to put small 2 leg pullers through?!

[SMdude]

Whatever you do, don't attempt to remove it by pulling from the outside!
2 largeish screwdrivers(or suitable lever), go in behind the fan and push off from the hub in the center.
When pushed from the back like that they normally come straight off. A small amount of heat may be handy too if it doesn't want to let go. Don't melt it!!

Cheers

[CatalinaWOW]

I have occasionally had good luck with vibration and time.  Apply some pressure in the removal direction using weights and springs.  Tap it every once in a while, or set up some form of mechanical tapper.  On at least two occasions I have come back after a day or two to find the thing broken free from its stuck position and ready to come the rest of the way off.  I must warn you that on at least as many occasions it hasn't worked.

[amyk]

Alternatively, try cooling the shaft with freeze spray. The plastic might not like it much over ~70C or so but the shaft will be fine at -30C, which combined together gives you a much bigger temperature difference.

[KL27x]

Simple hack is to find a board that with the right thickness to just fit between the fan and motor and cut a slot in it. Slip it between fan and motor and use it as a lever and/or tap one end with the right size hammer.