Author Topic: Return line union leak  (Read 1291 times)

Offline Joolstacho

  • Wise & Enlightened
  • *
  • Join Date: Jan 2010
  • Posts: 1094
  • Karma: 7
Return line union leak
« on: 04.04. 2013 11:11 »
Arrgh! I've minimised most of the oil leaks on the SR, but the return line union at the oil tank is still *issing out, despite trying copper washers, fibre washers, crush washers in various configurations. It's a strange arrangement with the return line and rocker feed banjo union there together.
The parts manual shows just 2 washers. What gives? I bet it's simpler that I think!
Cheers
Jools

Offline lawnmowerman

  • Resident Legend
  • *****
  • Join Date: Dec 2009
  • Posts: 624
  • Karma: 8
  • 1959 Super Rocket. Kent, England
Re: Return line union leak
« Reply #1 on: 04.04. 2013 11:34 »
Hi Jools

Did you anneal the copper washers before fitting. Nowadays a lot of copper washers have been punched out of a sheet of copper leaving a ridge on the mating surfaces so it is worth flattening them on a sheet of emery paper before annealing.

Jim
1959 A10 SR
1938 Wolseley 14/60
1955 Ferguson TEF20 tractor
1965 Ferguson 135 tractor
1952 Matchless G80 rigid
1960 BMW R60
1954 Matchless G80S
1955 Ariel 500 VH
1951 Sunbeam S7DL
1960 Matchless G12 with Watsonian Monza
......and loads of lawnmowers

Too old to Rock and Roll but too young to die  (Jethro Tull 1976)

Offline Joolstacho

  • Wise & Enlightened
  • *
  • Join Date: Jan 2010
  • Posts: 1094
  • Karma: 7
Re: Return line union leak
« Reply #2 on: 04.04. 2013 11:44 »
Yup, I always anneal before refitting.

Online orabanda

  • Wise & Enlightened
  • *
  • Join Date: Nov 2008
  • Posts: 1180
  • Karma: 24
Re: Return line union leak
« Reply #3 on: 04.04. 2013 13:36 »
Reminds me of a long time spend trying to get the two washers either side of the oil tank banjo to seal.

I had half a dozen other A10's with the same fibre washers; they didn't leak, but this &%^$&% did!

After much close scrutiny, the problem was a poorly soldered piece of 3/16" copper tube into the banjo; however it appeared to be coming from the washers!

The banjo / pipe piece was purchased new!

Since re-soldering myself; no more leaks!!!

Suggest you check this possibility.

Richard

Offline Joolstacho

  • Wise & Enlightened
  • *
  • Join Date: Jan 2010
  • Posts: 1094
  • Karma: 7
Re: Return line union leak
« Reply #4 on: 05.04. 2013 10:58 »
Good tip Richard, I'll check it tomorrow.

Offline mayes

  • Moving Up
  • **
  • Join Date: Mar 2013
  • Posts: 42
  • Karma: 0
Re: Return line union leak
« Reply #5 on: 05.04. 2013 13:27 »
when finishing to check they are flat lay on glass this is the best way i have tried to prove surface is flat John
bike running in rider running out
Tri 500 5Ta
B.S.A A10 1955 Under restoration

Offline Joolstacho

  • Wise & Enlightened
  • *
  • Join Date: Jan 2010
  • Posts: 1094
  • Karma: 7
Re: Return line union leak
« Reply #6 on: 10.04. 2013 11:10 »
Got the *astard! (Richard, take a bow).
But here's the thing. The leak turned out to be at the banjo/pipe solder joint, not the actual banjo / oil tank union itself.
After reassembling the thing 3 times trying various types of sealing washer, I pulled it all out and pressurised the banjo and pipe with air and so found the leak. I desoldered it, cleaned it up, annealed it and resoldered it using silver solder. Job done.
Now for the last leak... Yes, that gearbox/primary case drip. I've tried to fix this one before, carefully aligning the sliding plate etc, but no good.
I believe there's an oil seal conversion for this joint? Anyone got a fix for this that doesn't cost a wad of money?
-Jools

Online bsa-bill

  • Wise & Enlightened
  • *
  • Join Date: Mar 2006
  • Posts: 5720
  • Karma: 66
Re: Return line union leak
« Reply #7 on: 10.04. 2013 11:25 »
I have a return line leak in the same place, never thought of the line so thanks Jools I'll check mine now (well soon)

Quote
that doesn't cost a wad of money?
well fancy reading those words in a mail for old bikes  *smiley4* *smiley4*
All the best - Bill
1961 Flash - stock, reliable, steady, fantastic for shopping
1959 Rocket Gold Flash - blinged and tarted up  would have seizure if taken to  Tesco