lubrication for oven fan

[Bill Wright]

As per header. What's the best stuff to use?

Bill

[Bob Minchin]

Ordinary light oil will do the job. Bearings are normally sintered bronze oilite types and you just want to get some fresh oil to soak in.

hth

Bob

[Andrew Gabriel]

Sleeve bearings, I presume?

ISTR Geoff covering this a long time ago WRT boiler fans, and that it needs a special oil which is soaked into the bearings under special conditions (heat, vacuum, or something like that). You might be able to find this post on Google.

However, I suspect that if the bearings have got to the point of you noticing they need attention, they are probably only temporarily repairable, in which case it probably doesn't much matter what you use, but you'll want to clean off any gunked up oil/dirt first.

[The Natural Philosopher]

Experience in model aircraft electric motors equipped with plain bronze/steel bearings suggests that light machine oil (3 in one) will cure squeals, but if the bearing has run dry to the point of chattering and destroyed the bronze, or its its a ball race that has seized, bearing replacement or a new motor is the only solution.

In this case if light oil doesn't work replace the fan unit complete.

[Bill Wright]

I was assuming that light oil would catch fire in an oven.

Bill

[The Natural Philosopher]

ovens are really not that hot.

up to 200C at most.

That;s well below the flashpoint of most oils.

And I am fairly sure that most fans blow IN not out. So they are running a lot cooler than that.

[Gazz]

Some go higher.... but on a cleaning cycle,

My parents have just got a new built in oven, it has a feature that when activated, locks the door and takes the temp upto 600 degrees C, burning off all grease and crap,

They recently tried it, and said it works brilliantly, just a little bit of ash on the bottom to sweep out afterwards.

Tho i imagine the fan used on that oven is either well out of the heat, or uses an oil suitable for the high temps.

[harry]

If a sintered bronze bearing has run dry,the micro holes on the bearing surface are "wiped over" and disappear.

This means lubricant held within the sintered metal is no longer released on to the bearing surface. (Probably used up anyway.) If you going to oil them, it therefore needs to be long before they run dry. It wont get into the sintering as per it originally was even then.

So any oil/lubricant you add will only have a temporary effect anyway.

[Andrew Gabriel]

There must be several other DIY uses for that... ;-)

[harry]

The shaft on quality ovens fan motors is fitted with a thermal break device to stop heat transferring along the shaft

[Brian Gaff]

I think it tends to evaporate, not enough of it to actually do much, but I'd have thought it should be non toxic at least.

I don't fancy Lamb with 3in1 sauce.

Brian

[Graham.]

Count me out. I've opted for burial.

[sm_jamieson]

A "hot" oven is generally 250C. Both my ovens (built-in and combi) have max at

250C, but the built-in one also has a 275C setting for use with the catalytic cleaning mode. Simon.

[Grimly Curmudgeon]

Best use whale oil, then.

[Clive Page]

I've found it necessary to re-oil the fan motor in our oven every year or so for a good many years. No conflagration yet (but some odd smells immediately after re-oiling). I don't think the fan gets as hot as the interior of the oven.

[geoff]

In message , Andrew Gabriel writes

If the shaft is 6mm, we can generally repair them

[geoff]

In the case of sintered bearings, its absorbed into the phosphor bronze, its not pooling in the cooker

Ball races don't run in oil, they run in grease. Oil will only give a temp. fix

[geoff]

In message , Grimly Curmudgeon writes

What,. After the initial application of snake oil in the advertising department?

[Frank Erskine]

Don't the fans merely circulate the air? So the temperature will be much the same whether sucking or blowing...

In fact, don't they have two fans - one to circulate the hot air and another to cool the outer casing, which is of course the one that runs on after you've turned the oven off?

I think I'd be considering graphite or PTFE for lubrication at these sorts of temperature.

[The Natural Philosopher]

usual error.

Ball races of a light variety will seize in grease.

You need a very light anit-corrosion protection or nothing muvjh at all fora ball race.

Only stuff under big lateral forces needs any 'lubrication'

Anyway the result is the same: once ball races go, there is no way back usually.,