Johnson HD-25 Low Speed Insert Lead Seat

[Buccaneer]

On the HD-25 I’m working on, the Low Speed Insert / Nozzle
(that’s lightly pressed in the crankcase) must need a new
lead seat, as the insert is too far in and the needle body was hitting
on the crankcase, perhaps preventing a good seal on the nozzle.
The parts manual says it’s part 43-298.
The repair manual calls it a "lead seat" with "small ribs",
that should face "down".

I’ve searched for lead washers, and see nothing that small.
(3/8" OD, 1/8" ID )

Needless to say, I’ve search the original part number and get "no hits".

Any suggestions on what I could use for a lead seat?
Thanks.

Prepare to be boarded!

[ede]

Sent you a PM, Ed

[Buccaneer]

Ed, I PM’d you back, but it’s sitting in my outbox.
Either your mailbox is full, or perhaps it sits in
my "outbox" until you read it?

Prepare to be boarded!

[Mumbles]

If you find a NOS one, let me know what they look like as I’ve wondered before if they couldn’t be cut out of lead flashing material.

[Buccaneer]

I ordered a couple of NOS ones from
an AOMCI member 🙂
and I will post a photo with measurements upon arrival.
Good idea on the lead flashing material….. haven’t
seen any of that in the 100 years though… wonder
if it’s still used?

Prepare to be boarded!

[PugetSoundBoater]

In regards to lead flashing availability ,think i saw it at a roofing or plumbing supply company in Seattle last year. EDIT

"Some people want to know how a watch works, others just want to know what time it is"
Robbie Robertson

[Mumbles]

Keep your eyes open for an older house getting a new roof put on. Usually the roofers will replace the lead flashing on the vent pipes with modern plasticky ones and trash the lead ones.

[garry-in-michigan]

Diecast holes in castings are made with a slight taper to be easier to take out of the mold. This taper is what holds the low speed intake venturi in place. It may be removed in the very rare case of a blockage unable to be cleared by unscrewing and polishing the low speed needle. Know that each time this is done, the hole wares a little bigger. My solution to one that was too lose was to roll the slow speed venturi insert between two pieces of course sand paper to toughen the surface and then coat it with high strength LockTight and install it to the proper depth. After a few days, I clean it thoroughly and install the fuel line and needle valve. If this fails a thin lead tube with a shoulder on one end is used to take up the space. I saw one that had oil around the insert. It rotated easily when I disconnected the fuel line. Some one had used a Helicoil in the crank case and had threaded the insert. It was imposable line up properly. It was in to far or out too far. I settled for out too far with a lot of sealer on the threads. Sure to cause problems for the next mechanic that doesn’t realize it has been threaded. . . 😀

[Buccaneer]

Garry, my low speed insert / nozzle pried out easy with two screw drivers.
I was thinking about using a little loc-tite upon installation.

When I get the new lead seal, should I attempt to "dig" out
the old one, or just add the new on top of old?

Looks like it might be a pain to dig out. I suppose one could
split the crankcase, but not sure one could "poke" at the
old seal from the inside of the front case?

Is there a proper distance these nozzles should be installed at?
I see nothing in the manual about that.
Mine was "bottomed out".

The inside of my nozzle hole appears a little "out of round",
like a used sand blast nozzle gets.
Will this affect the performance of the engine?
Thanks!

Prepare to be boarded!

[garry-in-michigan]

Basically what I know is in the Johnson service manual . . . 😀

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