I have an oily problem with a dynamo on an old engine. Oil leaks from
the engine, past the drive gear, lubricates a ball bearing (which it
is supposed to do), defeats a felt seal and then soaks the dynamo
windings.

If I replace the ball bearing (an RLS4) with a sealed version will
this stop the oil flow and negate the need for the felt seal? I figure
that if the seals can keep the lubricant in the bearing then they
should be stop the oil even getting to the felt seal let alone the
windings.

Comments?

Charles

http://www.homeworkshop.org.uk

On Tue, 15 Jul 2008 13:17:13 +0100, Charles Ping
 wrote:

>I have an oily problem with a dynamo on an old engine. Oil leaks from
>the engine, past the drive gear, lubricates a ball bearing (which it
>is supposed to do), defeats a felt seal and then soaks the dynamo
>windings.
>
>If I replace the ball bearing (an RLS4) with a sealed version will
>this stop the oil flow and negate the need for the felt seal? I figure
>that if the seals can keep the lubricant in the bearing then they
>should be stop the oil even getting to the felt seal let alone the
>windings.
>
>Comments?
>
>Charles
>
>http://www.homeworkshop.org.uk

Charles

	I suspect a modern 'sealed' bearing will significantly reduce the
oil flow through the bearing. However, another option I know to have been
successfully used in similar situations is for the felt to be immersed in
hot tallow (candle fat) prior to installation! 

	It's worked for me in the past when it was used very successfully
on leaky wheel bearing felts which leaked onto thee brake shoes of an older
car.
--

Chris Edwards (in deepest Dorset)      "....there *must* be an easier way!"

On Tue, 15 Jul 2008 13:17:13 +0100, Charles Ping
 wrote:

>I have an oily problem with a dynamo on an old engine. Oil leaks from
>the engine, past the drive gear, lubricates a ball bearing (which it
>is supposed to do), defeats a felt seal and then soaks the dynamo
>windings.
>
>If I replace the ball bearing (an RLS4) with a sealed version will
>this stop the oil flow and negate the need for the felt seal? I figure
>that if the seals can keep the lubricant in the bearing then they
>should be stop the oil even getting to the felt seal let alone the
>windings.
>
>Comments?
>
>Charles

How much crankcase pressure is there from the engine?

A sealed bearing will be fine.

Peter
--
Peter A Forbes
Prepair Ltd, Rushden, UK
peterforbes@prepair.co.uk
http://www.prepair.co.uk
http://www.prepair.eu

On Tue, 15 Jul 2008 13:34:46 +0100, Peter A Forbes
 wrote:

>On Tue, 15 Jul 2008 13:17:13 +0100, Charles Ping
> wrote:
>
>>I have an oily problem with a dynamo on an old engine. Oil leaks from
>>the engine, past the drive gear, lubricates a ball bearing (which it
>>is supposed to do), defeats a felt seal and then soaks the dynamo
>>windings.
>>
>>If I replace the ball bearing (an RLS4) with a sealed version will
>>this stop the oil flow and negate the need for the felt seal? I figure
>>that if the seals can keep the lubricant in the bearing then they
>>should be stop the oil even getting to the felt seal let alone the
>>windings.
>>
>>Comments?
>>
>>Charles
>
>How much crankcase pressure is there from the engine?
>
>A sealed bearing will be fine.
>
>Peter

almost none - it vents all over the place (lately all over the
magneto)

Charles

Charles,

A sealed bearing is only as good as the seal which is fixed but the inner 
must still rotate therefore there must be a gap. The seal is generally to 
retain the grease and keep out the dirt.


Martin P
"Charles Ping"  wrote in message 
news:fj6p74pkfvssafbo419migcsds5gcne3jl@4ax.com...
> On Tue, 15 Jul 2008 13:34:46 +0100, Peter A Forbes
>  wrote:
>
>>On Tue, 15 Jul 2008 13:17:13 +0100, Charles Ping
>> wrote:
>>
>>>I have an oily problem with a dynamo on an old engine. Oil leaks from
>>>the engine, past the drive gear, lubricates a ball bearing (which it
>>>is supposed to do), defeats a felt seal and then soaks the dynamo
>>>windings.
>>>
>>>If I replace the ball bearing (an RLS4) with a sealed version will
>>>this stop the oil flow and negate the need for the felt seal? I figure
>>>that if the seals can keep the lubricant in the bearing then they
>>>should be stop the oil even getting to the felt seal let alone the
>>>windings.
>>>
>>>Comments?
>>>
>>>Charles
>>
>>How much crankcase pressure is there from the engine?
>>
>>A sealed bearing will be fine.
>>
>>Peter
>
> almost none - it vents all over the place (lately all over the
> magneto)
>
> Charles
>
>

On Tue, 15 Jul 2008 14:12:11 +0100, "campingstoveman"
 wrote:

>Charles,
>
>A sealed bearing is only as good as the seal which is fixed but the inner 
>must still rotate therefore there must be a gap. The seal is generally to 
>retain the grease and keep out the dirt.
>
>

a Z (shielded) bearing will have a gap, but an RS (Rubber seal) bearing won't
have a gap. A 2RS bearing is probably indicated in this application,



Mark Rand
RTFM

Mark,
Agreed but oil pressure will break through over time.

Martin P

"Mark Rand"  wrote in message 
news:tbsp74pt1hjiku62pjvtki86l44dafc5d7@4ax.com...
> On Tue, 15 Jul 2008 14:12:11 +0100, "campingstoveman"
>  wrote:
>
>>Charles,
>>
>>A sealed bearing is only as good as the seal which is fixed but the inner
>>must still rotate therefore there must be a gap. The seal is generally to
>>retain the grease and keep out the dirt.
>>
>>
>
> a Z (shielded) bearing will have a gap, but an RS (Rubber seal) bearing 
> won't
> have a gap. A 2RS bearing is probably indicated in this application,
>
>
>
> Mark Rand
> RTFM

"campingstoveman"  schreef in bericht 
news:geOdnb-DRuDAYuHVnZ2dnUVZ8gOdnZ2d@bt.com...
> Mark,
> Agreed but oil pressure will break through over time.
>
> Martin P
>
> "Mark Rand"  wrote in message 
> news:tbsp74pt1hjiku62pjvtki86l44dafc5d7@4ax.com...
>> On Tue, 15 Jul 2008 14:12:11 +0100, "campingstoveman"
>>  wrote:
>>
>>>Charles,
>>>
>>>A sealed bearing is only as good as the seal which is fixed but the inner
>>>must still rotate therefore there must be a gap. The seal is generally to
>>>retain the grease and keep out the dirt.
>>>
>>>
>>
>> a Z (shielded) bearing will have a gap, but an RS (Rubber seal) bearing 
>> won't
>> have a gap. A 2RS bearing is probably indicated in this application,
>>
>>
>>
>> Mark Rand
>> RTFM
>
As written previously, they are only to keep dirt out and grease in. I only 
know of the black rubber oil/grease sealing rings.for this purpose.
Dirk