[Fot] TR3 main seal question

[Steve Belfer]

Thanks again, Tony.  Y'know, I thought it looked like it was designed to 
pump the oil back into the block.  It worked well before so I'm not going to 
do the mod.
I'd call this an "Anti-Leak pump, rather than a seal. "   :)

~Steve
----- Original Message ----- 
From: "Tony Drews" <tony at tonydrews.com>
To: "Steve Belfer" <colordog.1 at earthlink.net>; "Friends of Triumph" 
<fot at autox.team.net>
Sent: Saturday, August 11, 2007 12:02 PM
Subject: Re: [Fot] TR3 main seal question


> That's a "scroll seal".  The grooves in the crank spiral from the flywheel 
> toward the inside of the block.  The theory, as I understand it, is it 
> will sling the oil back into the block.  If you get the aluminum halves 
> really close to the crank, it kinda works too.  The common modification is 
> to get the rubber seal kit from BFE or Moss (maybe British Parts Northwest 
> ?).  In order to use that kit, you need to have the scroll seal machined 
> off of the crank so it's a nice flat surface of the correct diameter. 
> Then the aluminum halves are machined to fit a relatively normal seal.  I 
> believe the machined housings come with the kit.  But, it's a split seal 
> so you can get it around the crank.  It's still not a perfect solution and 
> is a bit finicky to get to seal.
>
> Cambridge sells a crankshaft and flywheel where the whole flange at the 
> end of the crank is not there.  The seal diameter continues to the end of 
> the crank.  That allows you to slip a normal seal over the end of the 
> crank and make it really stop leaking (at least from the rear main).
>
> I just test the oil puddle under the drain hole in the bellhousing every 
> so often to see if it's motor oil or tranny fluid.  (stick a finger in it, 
> rub it together, smell it for the gear lube sulfur smell)  If it's motor 
> oil, and the puddle isn't too big, I figure all is OK.
>
> - Tony Drews
>
> At 01:10 PM 8/11/2007, Steve Belfer wrote:
>>I've just dissassembled my spare TR3 race motor and taken the parts to a 
>>local
>>machine shop and here's a silly question.  When looking at the two 
>>aluminum
>>half-circle's that bolt up to the block with the eight bolts (the main 
>>seal
>>assy.)  What the heck keeps the oil IN?  I see three or four grooves on 
>>the
>>crank where it fits into the seal that appear to match up with the grooves
>>inside the seal.  If the crank spins freely, what exactly keeps the
>>pressurized oil from blowing past this circular seal?
>>
>>Please, no leaky triumph jokes ;)
>>
>>~Steve