Angle Grinder Refurb

[Turbo]

My parkside 5" grinder started making a funny noise last time I used it so I decided to investigate.

Removed the guard & cleaned the outside to avoid any crud falling into the gearbox.

Used an engraver to add alignment marks on the housings.

There was plenty of grease in the gearbox, just not in the right places! The big wheel was dry and there were some burrs on the teeth but no major damage.

The main bearing was very rough and there was no grease in the front end of the gearbox at all. Not that it mattered as they had left the inner seal in the bearing meaning it couldn't get any fresh grease!

Front of gearbox stripped & cleaned.

When I was this far I decided to check out the motor bearings. Good job too as the gearbox side one was very rough. Problem was I could see no way of getting it out. I couldn't get the shaft driven out from the gearbox side and the outer race was held in with a plate & 2 screws, covered by the cooling fan.

After some head scratching I decided to melt a hole in the fan so that I could remove the 2 screws securing the outer race.

A bit of wriggling & it all came apart!

All apart, cleaned & new bearings ordered.

 

[rtbcomp]

You've probably put the fan out of balance - you may need another hole opposite the one you've made.

 

[pedrobedro]

I wouldn't worry about the fan it's not big enough to make much difference and the hole is near the centre of rotation so not much effect. The bearing went in so there must be a way to get it out but yours worked.

 

[RonA]

Put some new bearings in my very, very old B & D grinder some years ago, amazing what a difference it makes. Bearings cost not a lot & saved the cost of a new grinder.
RonA

 

[Turbo]

You've probably put the fan out of balance - you may need another hole opposite the one you've made.

I did think about doing that but I'm worried that another hole might weaken it.

I wouldn't worry about the fan it's not big enough to make much difference and the hole is near the centre of rotation so not much effect. The bearing went in so there must be a way to get it out but yours worked.

I reckon the bearing was fitted in the casing first & the motor shaft was pressed into it. But due to the shape of the gearbox housing you cannot get a straight push at the shaft to press it out again.

 

[armalites]

Interesting what you said about the grease, I took my 25 year old B&D grinder apart at the weekend to check it out/clean it. The was not a bit of grease in the gearbox and there never had been, it was clean as a whistle in there. I did grease it but I'm getting concerned now that maybe it was better without grease.