More (and different) oil line questions

[DJinCA]

I am working on the oil lines for my 51-52 plunger A10 rat bike.  I originally ordered a 67-0450 as shown in my parts book.  I received the one piece line shown in the photo below.  Unfortunatly(?) the lower fitting (shown in the second image) on the line that should connect to the oil tank at the return connection appears to be the same as the fittings that connect to the rocker shafts.  I am thinking that this can't be correct, as I see no way it would seal between the oil pipe connection (65-8420) and the oil return pipe nut (65-8424) 

I looked at some other models and found that I might use 65-1547(shown in the third image with pipe connection and nut).  It looked to me as though it was also meant to be used with the same pipe conneciton and nut, however when I put the together and gave a gentle tightening with a pair of wrenches, the connection leaked with just the pressure of my breath.  If I had machine tools, I would modify these or make something that fits, but I am at a bit of a loss as to how I should proceed now.  Should 67-0450 have a different fitting on it?  The only place I see it on this side of the Atlantic is Randy Baxter's, and the photos don't show that end of the pipe.  Should I be looking at some other option?  Should I continue to try to seal up what I have with some hand tools and perhaps some lapping?

DJinCA



Your guidance would be appreciated.

[orabanda]

Hi DJ,
When tightened, sealing is achieved by metal to metal contact on the tapered faces.
A firm nip up is all that is required; if you get too excited you could snap the fitting.
Pics are from my 51 plunger; no leaks.

Richard

[DJinCA]

Hi Richard,

Thanks for the reply.  I take it from your response that I should be on the right track.   I can see how it is supposed to seal, and I did snug the connection up with wrenches, but it still leaked with the little pressure developed by my breath.  I was firm enough with wrenches that I wouldn't want to tighten the connection much more for fear of snapping a fitting.  I think that I will put some blue on the fittings and tighten them to see if I see any problem spots.

DJinCA

[RichardL]

Just being an amused observer with no knowledge about plunger oil supply (or, maybe, anything), I ask the question, is the banjo at the oil tank supposed to fit between the two tapers in the hose fitting? If so, I don't see how it could be right if it's flat on one side? (Whatever happens, listen to Richard "Orabanda.")

DJ, if it's not being too personal, whereabouts in California are you located? I'm originally from the San Fernando Valley.

Richard L.

[DJinCA]

Hello RichardL,

I know that Richard "Orbanda" is a well repsected contributor on this forum, and I value his advice.  I guess that I wasn't clear in my original post, but I did tighten the connection to a degreee that I would have thought to be adequate for it to seal if it was going to do so.  The banjo on the fabricated line is supposed to seal between the taperred faces on the nut and connector shown in the third image.  I purchased the 65-1547 line and banjo fitting also shown in image 3 (which appears to be symetrical with the same aperture and taper on either side) as it was obvious to me that the banjo shown in image 2 would not seal.  It is my belief that the fabricated line with three banjos is either not the part I ordered, or constructed incorrectly.

I am in the San Francisco Bay Area.

DJinCA

[orabanda]

Hi DCinCA, and RichardL (flattery appreciated BTW!)

The correct oil line for the plunger is the longest one piece pipe, with the paired rocker banjos on one end, and the banjo on the other end which is locked between the metal surfaces of the two fittings at the oil tank.

The metal to metal seal will work fine; when the banjo sits concentric between the two fittings, there is a point contact for 360 degrees, on each fitting. From memory (and I might be wrong about this) the tapers are 30 degrees.

Suggest you grab the fitting which screws into the tank in a vice. Set the proud tapered face that the oil line banjo sits on, facing upwards. Check the taper is perfectly smooth and no scratches , dings, etc on the sealing face. Give it a rub with very fine wet & dry.

Do the same checks on the male tapered face of the other (outer) fitting; the oil line pushes on to.

Then do a "dry" assembly and firmly tighten the outer fitting.

Disassemble and check for an uninterrupted line on each face, where the banjo end has seated on each face. The arrangement wont leak if you can see the continuous contact at each face.

Reassemble with a thin smear bearing of bearing (Prussian) blue, which will make it easier to see the metal to metal contact. Or, chalk or talcum powder.

Also, use a sealant (569 Loctite is perfect; with Primer T recommended) for the male thread on the oil tank, when screwing on the inner fitting.

Happy days, cobber!!

Richard

[DJinCA]

Thanks Richard,

So, am I correct in thinking that the correct bottom fitting on the pipe ought to look somthing like the fitting in image 3?  I will try putting some blue on it and check the fit, then see if I can lap it all together.  I can put a piece of hose between the  two once I part off the incorrect fitting.

Thanks again,
DJinCA

[orabanda]

The two fittings in the bottom RH corner of pic 3 look like the correct items.

[RichardL]

Who knows, I'm only in my 70's, maybe some day I'll own a plunger and may need to know this. Shouldn't the mating surface shown in photo 2 be a 30 degree bevel instead of flat, as shown?

Would this be a good time to throw in something about anti-seize vs. Loctite?  (A side joke DJ, nothing to do with your topic.)

Richard L.

[Greybeard]

Shouldn't the mating surface shown in photo 2 be a 30 degree bevel instead of flat, as shown?

The flat surface on the spigot is for the flexible hose.

Below that you can see the two bevels that clamp the pipe banjo.

I wonder if the threads are bottoming before the seal is made.

The whole rocker feed arrangement is obviously an afterthought. It's not an elegant design.

[Swarfcut]

   That banjo on your new pipe is simply wrong. The correct banjo has identical female tapers on each side and easily seals between the tank  nut 65 8424 and  the pipe connector 65 8420, both having matching male tapers. Tank nut seals to the tank boss with a small fibre washer, 65 8421.

   Depending on availability of correct parts, any oil tight arrangement that maintains the oil flow path will do for now. Not correct I know, but better than holding up the job. With the variable quality and attention to detail on pattern parts GB's point about the threads could be the answer, together with the already mentioned checks to the taper angles and surfaces.  Your latest banjo, if double sided looks to be worth a try.

 The single piece pipe has a convoluted route is prone to fracture and needs supporting at intervals. Later S/A models use a two piece set up with a flexible joining tube, so unless true concours standard is the aim, simply cut and shut as required.

  Swarfy.

 

[Greybeard]

That banjo on your new pipe is simply wrong.

Well spotted! That banjo is deffo wrong.

Additional:
We may not be looking at the correct banjo. I don't recognise that short pipe in the first picture. Can we see more of the banjo at the bottom of the long pipe?

[RDfella]

That banjo looks like the rocker feed end

[RichardL]

That banjo on your new pipe is simply wrong.

Well spotted! That banjo is deffo wrong.

G.B.,

I couldn't get an atta boy?

Richard L.

[DJinCA]

Thank you all,

The bottom banjo on the long pipe (alledgedly 67-0450) is identical to the banjo fittings for the rocker shafts. When I had all the parts in front of me it was clear that it could not be made to seal with the connector (65-8420) and nut (65-8424) so I never tried to do anything with it.  The end of the shorter pipe (65-1547) is shown in the third image with the connector and nut.  It is symetrical with a female beveled mating surface to seal with the nut and connector but mine currently doesn't.   I do have the fiber washer, 65-8421 to seal on the tank.

I will proceed with getting the  joints to seal using the 65-1547 short pipe.  I have layout blue for a gross fit and prussian blue to finish it, along with papers down to 2000 grit as well as some lapping and grinding compounds.  I will trim the 67-0450, removing the incorrect lower fitting, and the 65-1457 to convenient lengths and join them with a piece of hose.  Originality is not an issue on this bike, I am plumbing in an oil filter too while I am at it.

Thanks for the advice and confirmation that I might be on the right path.

DJinCA