Which part to replace? (Worcester heatslave 15/19)

[Burnerman]

Two bearings needed (6202)......2RS are rubber sealed, and 2ZZ are metal sealed.
I use 2ZZ bearings all the time.
If you find the bearings stuck in the housing, heat the housing with a hot air gun and the bearings will drop out.
If they are stuck on the motor shaft, either use a puller or grip the bearing in a vice, and gently tap the rotor shaft end.
John

 

[CT846]

Two bearings needed (6202)......2RS are rubber sealed, and 2ZZ are metal sealed.
I use 2ZZ bearings all the time.
If you find the bearings stuck in the housing, heat the housing with a hot air gun and the bearings will drop out.
If they are stuck on the motor shaft, either use a puller or grip the bearing in a vice, and gently tap the rotor shaft end.
John

Hi John, thanks very much for the advice. I'll order a couple of the ZZ's & let you know how I get on. Also thanks for the tips! I've also heard that a car windscreen wiper arm retracter can be handy to pull the bearing. Luckily I bought one of them for the car last summer!
Cheers,
Craig

 

[Burnerman]

I don't think that puller will do, Craig (There's a picture link in the car section, Corsa wipers, solution courtesy of ch427) but worry ye not, they aren't that tight (usually )
As before, gently holding the bearing in the vice only squeezes the outer race so that and a sharp tap on the shaft should get it off.
Hold the rotor so it doesn't drop on the floor!
John

 

[Agile]

John, I was wondering about the 2RS and obviously you have thought like me and only use 2ZZ.

Why were the 2RS fitted initially?

 

[Burnerman]

I can't think of any reason engineering wise why the RS bearing would have an advantage over the ZZ......maybe its all that was available at the time of manufacture or they were cheaper!
After all, they are both sealed bearings (although it is possible to open the RS for grease packing) but no one would really bother with that.
Certainly I would expect the ZZ to be more resistant to heat, so maybe thats the preferred replacement these days.
John

 

[Agile]

The 2RS are normally used when water may be present.

But I dont see that being relevant here.

I think the skate boards may be fitted with the 2RS.

Perhaps as you say they were a penny cheaper but most fans I see have the 2ZZ fitted.

Tony

 

[Burnerman]

I imagine the reasoning behind the rubber seal would be to repel kerosene leaks from the oil pump better than the steel seal.....however, if the leaks are as bad as that I would thought the fate of the bearing would be the least of all concerns!
John

 

[CT846]

Hi. A quick update. The new 6202 2ZZ bearings arrived and changing them over was fairly straightforward (one stubborn bearing to remove from the shaft!). The old bearings were definitely worn! The boiler is now back to running nice & quietly.

I'm going to order a new burner nozzle while I'm at it & then have it fitted during a service this week (also so that the pressure / CO2 levels etc can be checked).

I believe that the burner is made by Danfoss. I'm pressently using a 0.75 x 80EH nozzle, which gives me 22.5KW, but am considering replacing this with a 0.60 x 80EH nozzle, which would give 20KW output (having done a rough BTU calculation it looks like this should be OK... and might save me a bit of oil?!). Is there any preference between nozzle manufacturers (I see that Delavan seem to get recommended), or should I just stick with Danfoss?

Thanks very much for the help & advice.

Craig

 

[Flightrisk]

Holy thread resurrection.........
Just a note for anyone finding this thread for info on changing the bearings.

2 x FAG or SKF - 6202 ZZ, which are available on ebay

If you don't have a puller, be careful what you tap the fan shaft with, as it can deform, making the job of refitting the fan a lot more tricky than it needs to be.
The fan came off fairly easily, but the fan end bearings on mine, were firmly stuck on the shaft.
They came off by clamping the bearings in a vice and applying many light taps with a hammer.

On refitting the fan though, it absolutely refused to fit back onto the shaft, necessitating in a good hour spent with a fine file and glass paper, being as careful as possible.

Got there in the end and it now runs silently and no longer leaks from the crappy bulkhead valve as well.

Just the weeping oil pump and the expansion vessel left to do.

Touch wood.

 

[oilhead]

Just the weeping oil pump and the expansion vessel left to do.

Touch wood.[/QUOTE]
You really need to address the weeping oil pump immediately. This is probably what caused the motor problems to start with. I really do not understand the penny pinching 'professionals' who change bearings. The cost of the time time taken, versus using a new reliable motor are pretty even. Factor in the uncertainty of the result or problem in repairs make it a no brainer IMHO.

 

[oilboffin]

Nice one oil head I agree 100% with what you say I've followed PROFESSIONALS who've changed bearings and two weeks later I've changed the motor or the so called tech who has fixed the pump and I've been back and changed the pump.Why do they do it.Bob

 

[Terrywookfit]

Nice one oil head I agree 100% with what you say I've followed PROFESSIONALS who've changed bearings and two weeks later I've changed the motor or the so called tech who has fixed the pump and I've been back and changed the pump.Why do they do it.Bob

Because they can !!
It must make them feel good.
I once changed the shaft seals on a Mectron oil pump......Two weeks later the fookin shear pin gave up.
Only parts I change are sol coils and pressure reg seals.

 

[oilboffin]

God I bet the air was blue and yes I change the seals on the pressure reg it don't take long and it can be a lasting repair.Bob

 

[Flightrisk]

Just to clarify (and offset the snarky comments), the slightly weeping oil pump is from the o rings on the front.

No oil leaking along the shaft onto the bearings, or I would have changed it.

So 20p for a couple of new o rings, or £100+for a new pump..........

 

[Terrywookfit]

Just to clarify (and offset the snarky comments), the slightly weeping oil pump is from the o rings on the front.

No oil leaking along the shaft onto the bearings, or I would have changed it.

So 20p for a couple of new o rings, or £100+for a new pump..........

A Ton plus for a BFP pump ???......Less than 40 + Vodka !!!