Intake nipple sealer question

[gitguy]

Does anyone have evidence that the MOCO used any sealer, Folks?

Thanks in advance,

....Cotten

Did the MOCO use PEEK seals or bubble test each motor for intake leaks before it left the factory?

[HDSmitty]

Now THAT'S funny stuff right there, Gitguy

[T. Cotten]

Does anyone have evidence that the MOCO used any sealer, Folks?

Thanks in advance,

....Cotten

Did the MOCO use PEEK seals or bubble test each motor for intake leaks before it left the factory?

That's a great question, Gitguy!

There is a mention of bubble-testing in the Panhead manual compilation, but I think it was for oil pumps (somewhere around page 300 or so..)

We can be pretty certain about PEEK though.

Back to topic:
I suspect Chief cylinder nipples were sealed with white lead.

NPLSEAL2.jpg
NIPLSEAL.jpg

....Cotten

[exeric]

Tom, I've wondered if H-D used a sealant on intake nipples and would think they would just to cover manufacturing imperfections. I know on pocket valve Js they used a substance called 'plumbago' to seal the intake housing to the cylinder. I would think the white lead that plumbers used would both lubricate, and help seal a threaded nipple. If you could still buy white lead, I'd try it.

[T. Cotten]

Tom, I've wondered if H-D used a sealant on intake nipples and would think they would just to cover manufacturing imperfections. I know on pocket valve Js they used a substance called 'plumbago' to seal the intake housing to the cylinder. I would think the white lead that plumbers used would both lubricate, and help seal a threaded nipple. If you could still buy white lead, I'd try it.

The reason I ask, Eric,..

Is because I have yet to find any evidence of any in the fossil record.

How'd they get away with it?

....Cotten

[Steve Swan]

Tom, I've wondered if H-D used a sealant on intake nipples and would think they would just to cover manufacturing imperfections. I know on pocket valve Js they used a substance called 'plumbago' to seal the intake housing to the cylinder. I would think the white lead that plumbers used would both lubricate, and help seal a threaded nipple. If you could still buy white lead, I'd try it.

Gentlemen, correct me if i am mistaken as to what plumbago is... if i recall correctly, in the 1918 Motorcycle Repairer, plumbago is described as an oil/graphite mixture. Would like to learn more about the mixture. i can only imagine lapping those inlet housings to the cylinder for a perfect seal was critical.

[gitguy]

That's a great question, Gitguy!

There is a mention of bubble-testing in the Panhead manual compilation, but I think it was for oil pumps (somewhere around page 300 or so..)

We can be pretty certain about PEEK though.

Back to topic:
I suspect Chief cylinder nipples were sealed with white lead.

NPLSEAL2.jpg
NIPLSEAL.jpg

....Cotten

The only reason I mentioned this Tom, is that the technology has obviously improved over time and although using a "goober" to seal intake nipples might have been a fool's errand in the past, maybe using one of today's new and improved "goobers" might be an effective solution.

I had an intake leak on my 32 VL that was causing me fits. Finally at the recommendation of a friend I tried Hylomar blue sealant. I was reluctant but out of ideas. After that that the motor ran like a Swiss watch.

Your bubble testing advocacy has been one of the best tips I've run across. Thanks to you, I've made test plates for each of my bikes and having a no leak manifold makes a huge difference in how these machines run.

Thank you sir!

[T. Cotten]

Hylomar®, Gitguy,..

Remains fluid. Think about it.
(My point, once again, is that if a mechanical seal is achieved, then you cannot credit the goober,... unless it finally fails.)

Any goober expected to resist the ever-changing fuels should be thoroughly tested before investing time, energy, gut lining, and money.

My immersion testing last decade showed next to no non-hardening sealers survive. (One that did was Permatex's The Right Stuff® (Grey), but it says right on the label its not for gasoline!)

Even hardening epoxies like J-BWeld® required weeks of cure before it was fully resistant.

....Cotten

[exeric]

Gentlemen, correct me if i am mistaken as to what plumbago is... if i recall correctly, in the 1918 Motorcycle Repairer, plumbago is described as an oil/graphite mixture. Would like to learn more about the mixture. i can only imagine lapping those inlet housings to the cylinder for a perfect seal was critical.

Steve, I believe there is also lead in that plumbago mixture, possibly a lead powder, or white lead mixed with the oil, and graphite. I found this somewhat amorphous definition on the internet:

As nouns the difference between plumbago and lead

 is that plumbago is (mineralogy) graphite while lead is (uncountable) a heavy, pliable, inelastic metal element, having a bright, bluish color, but easily tarnished; both malleable and ductile, though with little tenacity it is easily fusible, forms alloys with other metals, and is an ingredient of solder and type metal atomic number 82, symbol pb (from latin plumbum ) or lead can be (uncountable) the act of leading or conducting; guidance; direction, course; as, to take the lead; to be under the lead of another.

[Steve Swan]

Steve, I believe there is also lead in that plumbago mixture, possibly a lead powder, or white lead mixed with the oil, and graphite. I found this somewhat amorphous definition on the internet:

As nouns the difference betweenà plumbagoà andà lead

à is thatà plumbagoà is (mineralogy) graphite whileà leadà is (uncountable) a heavy, pliable, inelastic metal element, having a bright, bluish color, but easily tarnished; both malleable and ductile, though with little tenacity it is easily fusible, forms alloys with other metals, and is an ingredient of solder and type metal atomic number 82, symbol pb (from latinà plumbumà ) orà leadà can be (uncountable) the act of leading or conducting; guidance; direction, course; as, to take the lead; to be under the lead of another.

Eric, thanks for that! Having lead in the mixture makes sense in that it melts and creates a seal...?

[T. Cotten]

Eric, thanks for that! Having lead in the mixture makes sense in that it melts and creates a seal...?

Uh Oh, Steve,...

The melting point of lead is ~620°F.

By that point, I would have expected the gas tanks to boil over.

...Cotten
PS: Lead is quite compliant at normal temperatures, and Indian used it for oil pump fittings.

[Steve Swan]

Uh Oh, Steve,...

The melting point of lead is ~620°F.

By that point, I would have expected the gas tanks to boil over.

...Cotten
PS: Lead is quite compliant at normal temperatures, and Indian used it for oil pump fittings.

Too funny, but not with tanks exploding! Thanks Tom, for the clarification! So, the idea using lead in plumbago was to provide a squish seal of sorts...?

[T. Cotten]

Too funny, but not with tanks exploding! Thanks Tom, for the clarification! So, the idea using lead in plumbago was to provide a squish seal of sorts...?

My first guess, Steve,..

Is that it served the same purpose as copper does in sealers today, except more toxic, and probably better.

....Cotten

[otis71]

Back to leaky rivets- I’ve found that the rivet holes are usually wallowed out and fitting a new rivet after making them round again is necessary. Generally an easy fix unlike pesky nipple threads.

[T. Cotten]

Back to leaky rivets- I’ve found that the rivet holes are usually wallowed out and fitting a new rivet after making them round again is necessary. Generally an easy fix unlike pesky nipple threads.

It was never easy for me, Otis!

First, I had to anneal spike nails in coals to cool overnight.

Next, the hole had to be reamed clean, and then a rivet cut from scratch to a light press-fit, with a tapered head to seal itself upon the inner surface of the nipple.

If I didn't already have an internal cam-action anvil, I had to make one.

With the anvil securely pressing and holding the rivet into the nipple on the inside, with a sealer of choice for luck, I could then trim it to length on the outside.

Then, hoping I still had two free hands, I could upset the exposed rivet, barrelling out its shank within the nipple and casting with minimal strikes, hopefully to appear like the originals, instead of an over-peened repair.

Then another bubble-test, and if successful, some rust protection.

Add at least an hour if its still in the chassis!

....Cotten