Introduction
When a New Haven clock stops as soon as it enters warning, the cause is almost always friction, misalignment, or interference in the strike train. Warning is the brief moment when the strike train is unlocked but held just before the strike sequence begins. If anything binds or drags at this point, the time train loses power and the clock stops. This guide explains how warning works and how to diagnose the underlying issue.
How Warning Works
Warning wheel rotation
When the minute hand approaches the strike point, the strike train unlocks slightly and begins to rotate.
Stop lever engagement
A lever catches the warning pin, holding the train until the exact strike moment.
Lift‑pin interaction
The center‑shaft lift pin raises the strike lever, releasing the warning stop at the correct time.
Power transfer
The strike train must rotate freely during warning; any drag stops the clock.
Time‑train sensitivity
New Haven movements are especially sensitive to added load during warning.
Common Causes of Stopping on Warning
Strike‑train drag
Dirty pivots, worn bushings, or bent arbors increase resistance.
Warning pin binding
The pin may be bent, rough, or catching the stop lever too tightly.
Stop‑lever misalignment
If the lever drops too deeply, the train cannot rotate freely during warning.
Lift‑lever friction
Excess friction in the lifting system adds load to the time train.
Hammer interference
A hammer resting too heavily on the gong adds drag during warning.
How to Diagnose the Issue
Test warning by hand
Advance the minute hand slowly and observe when the train unlocks and where it binds.
Check the warning pin
Ensure it is straight, smooth, and not catching the stop lever.
Inspect the stop lever
Verify it drops just enough to hold the train without excessive depth.
Check hammer lift
Hammers must not lift too early or too high during warning.
Test train freedom
Spin the strike wheels gently—any hesitation indicates drag.
Correcting the Problem
Step 1: Reduce strike‑train drag
Clean pivots, polish arbors, and bush worn pivot holes.
Step 2: Adjust the stop lever
Ensure it catches the warning pin lightly without binding.
Step 3: Correct hammer lift
Adjust hammer tails so they lift only when the strike actually begins.
Step 4: Verify lift‑lever freedom
Ensure the lifting system moves smoothly with no friction.
Step 5: Test warning repeatedly
Advance the hands through several cycles to confirm smooth warning and strike release.
Troubleshooting Flowcharts
If the clock stops entering warning
Strike drag → Warning pin binding → Stop lever too deep → Hammer interference
If the strike won’t release
Stop lever stuck → Lift pin too low → Warning pin misaligned → Train drag
If the strike is weak
Dirty pivots → Worn bushings → Hammer rubbing → Power loss
If warning is inconsistent
Lever wear → Pin burr → Lift timing off → Train misalignment
If the clock is tilt‑sensitive
Pivot wear → Train drag → Stop‑lever friction → Weak power
Common Mistakes to Avoid
Deep stop‑lever engagement
Too much depth prevents the train from rotating freely.
Over‑lifting hammers
Excessive hammer lift adds unnecessary load during warning.
Ignoring pivot wear
Oval holes drastically increase drag.
Running the clock dirty
Dirt acts as an abrasive and increases friction.
Skipping full‑cycle testing
Warning issues often appear only after several cycles.
Checklist for Final Verification
• Warning smooth and consistent
• Stop lever aligned
• Warning pin free
• Strike train clean and free
• Hammers lifting correctly
• Movement runs full 8‑day cycle
FAQs
Why does my clock stop when entering warning?
Because the strike train is binding or the stop lever is too deep.
Why won’t the strike release?
The warning pin or stop lever is misaligned.
Why is the strike weak?
Power loss from dirty pivots or worn bushings.
Why does the clock stop randomly?
Intermittent drag in the strike train.
Is this common in New Haven clocks?
Yes—warning sensitivity is a known characteristic of these movements.
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