Bulova Accutron 218D

The Railroad Approved wristwatch

Lately it’s begun to feel as if I’m proficient at starting a project but deficient when it comes to finishing one. I have a chronograph on the bench which has been in pieces since January, the Sprint chronograph I purchased in July is still incomplete, and I’ve been chasing my tail on a nice little Seiko for what seems like ages. Beginning to feel as though I was spinning my wheels I decided to switch gears and get organized.

I purchased a lot of Bulova and Caravelle parts from a watchmaker’s estate after I spied some tools hidden among the bits that I knew would come in useful. The parts were all new old stock (NOS) and still in their packaging so I thought I could probably sell some of them on eBay to recoup the money I extended for the lot. I set about cataloguing the bits and pieces when I came across a small tin which held about two dozen tiny gear wheels in Rodico. Confirming the wheels were in fact Accutron index wheels brought a smile to my face as they do have value.

IMG_2710In order to resell the index wheels I would need to make sure they were free of damage and this is a bit more difficult that one might think. I have a stereo microscope on the bench but the teeth on an Accutron index wheel are so small they are barely visible under the greatest magnification; the solution obviously was to purchase an Accutron to test the wheels. I opted for this sad looking piece as it was discounted due to it’s non-running state.

Like my father’s Accutron I repaired earlier, this is the second generation calibre 218 with date feature. The seller explained the watch did not run but pictures of the movement suggested this wasn’t the result of water damage. The watch arrived within two days of the sale and since none of my other watch repairs were progressing I went straight to work.

The stainless steel case displayed a lot of wear; the caseback in particular taking a beating over the years. The code M7 on the caseback dated this Accutron to 1967 making it a just bit older than my father’s watch. I could see from the grime that it had not been serviced in a while.

Caseback displays a bit of wear

The caseback is secured with a threaded ring. I don’t have the approved tool for removing the ring but was able to manage well enough using a small screwdriver. The first look at the movement was promising- no signs of rust or  battery acid.

The first look inside- it’s dirty but otherwise looks good!

Electric watches are often at risk of damage from leaky batteries as many owners will simply put a watch in storage when the battery charge fails. Over time the acid can escape the battery and can damage the circuitry. Unsightly staining also occurs on the plates when acid from mercury batteries chemically bonds with the gold plating.

The source of failure here became apparent when I was unable to secure the battery strap over a replacement cell. The screw for the hold down had seized and would need to be replaced. The movement was also in need of a good clean so I set to breaking it down.

Movement close-up. Note the shock spring on the top jewel- I hate these things!

I popped the movement out of the case and readied the hands for removal. The dial displays the standard Railroad Approved arabic numerals and is still in fine shape.

Beautiful dial

The bottom plate with calendar works was clean and scratch free. I noted the assembly of the calendar works is a bit different from the first Accutron I serviced. This is the calibre 218D which is apparently just a tad bit different from the 2181 I worked on before. I spent a lot of time on my hands and knees looking for springs during that job…

Bottom plate is in fine shape
Close-up view of the bottom plate and calendar works

In this movement I particularly liked how the date trip spring was secured to the calendar plate. I could see this feature would pay dividends during reassembly.

The date trip spring is held snugly in the calendar bridge

I broke down the bottom plate with the calendar works, hour & minute wheels, and setting mechanism before moving to the top plate.

Calendar works removed from bottom plate

I began work on the top plate by removing the jeweled train bridge. Most of the jewels are capped which require a bit of extra work to clean properly and lubricate.

Train bridge removed revealing gear train

The gear train came out before moving on to the fork and coils. The fork is highly magnetized causing it to attract much debris. A small paintbrush was used to remove any debris caught between the fork and coils.

The gear train is out leaving the fork, coils, and index finger

After completing disassembly, the staking set was put work to push out the seized screw and insulating grommet. Thanks to the internet a NOS replacement was not difficult to find.

I pushed the grommet through the wrong side of the plate causing it to break in two

I packed the movement in the cleaning machine and turned my attention to the watch case.

Dirty and scratched

The case was treated with warm water, dishwashing soap, and a soft toothbrush followed by a short bath in the ultrasonic cleaner.

Even though the watch case is made of stainless steel there is still a risk of oxidation (rust). I was disappointed to discover quite a bit of pitting around the threads for the caseback retaining ring. The owner must not have kept the case very clean. Accumulated grime will hold moisture in contact with the steel which results in the extensive pitting you see below. Unfortunately there isn’t much I can do about this but at least it doesn’t show when the watch is on the wrist.

Worst pitting on stainless steel that I’ve seen

The movement came out of the cleaner nice and tidy and was ready for assembly following a quick blow dry with the heat gun. As per the Bulova service instructions, the coils, fork, and index wheel all required a more delicate touch than the L&R cleaner could provide.

Cleaned and ready for assembly

The setting mechanism is the first bit to be assembled.

Setting mechanism installed and lubricated

The center wheel assembly is known to be problematic in Accutrons. The assembly should allow for the rotation of the wheel and pinion independent of one another but often they seize up (this particular problem blighted my father’s Accutron); I wasn’t surprised to discover that was a problem here.

Gripping the cannon pinion in a pin vise, the center wheel was broken free with a tiny bit of rotational force.

Center wheel assembly (center wheel and cannon pinion)

After a good re-clean and lubrication the center wheel assembly was installed.

Ready for the calendar works

The rest of the work proved uneventful as the movement came back together quickly. Even the new screw for the battery hold down didn’t put up much of a fight.

Ready for battery strap and battery
The dial is rescued and hands will be pressed on next

A new silver oxide battery brought the movement to life. Accutron enthusiasts call these watches “Hummers” as they emit a very distinct hum from the action of the tuning fork. I think a better nickname would be “Skeetos” because they sound a lot like mosquitos and just like the insect you can only here it when it’s right next to your ear.

Making final timing adjustments

Although not pictured above, I reinstalled the original rubber caseback gasket before buttoning up the watch. I learned a valuable lesson on my first Accutron repair and that’s not to discard the original gasket. Replacement gaskets are available but the size is slightly off resulting in the movement having a bit of play within the case. There’s a solution for this and that’s to find an original caseback spring which screws into the two recessed holes you see on the bridge to the left of the words Bulova USA. The tension from the spring will hold the movement tight in the case. Only the earliest model 218 Accutrons had this spring which makes replacements a bit difficult to come by.

Complete with a new crystal

This was a fun job. It’s one of my quickest repairs and was also quite painless since I only needed one replacement part. I love the Railroad approved dial too- simple and very easy to read.

Oh, and as far as testing out those index wheels? Well, I won’t need to do that with this watch because the seller threw in a second Accutron with my purchase. Keep a lookout as I’m sure it will be on the blog shortly.

Author: JPMoeller

Amateur watchmaker and California resident

3 thoughts on “Bulova Accutron 218D”

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