ripvanwinkel
Freshman Member
Offline
Good Day to All,
After many long years of rebuilding my BN4 LongbridgeHealey, I finally got to the unique little windscreen washer pump that was notworking after 30 years of stagnation. On stripping the unit, I discovered, asmany before me also have, that the diaphragm had hardened and was completelyperished. Many nights were spent contemplating a fix for this as I wished toretain originality in looks and functionality, i.e. a mechanical pump utilisingthe same body and external features.
My first thought was to replace the diaphragm with the cutoff middle finger of a latex glove, stretched over the brass end plate andcomplete with the small internal spring, which was still in good condition.This trial worked reasonably well, but I was concerned that the stretched areawould soon perish and not last the distance. Back to regular contemplation overmany nights!
I then had a Eureka! moment and decided to try the humblelittle squash ball! See pics attached.
This is the procedure I used:
I hope this helps those who wish to retain mechanicalfunctionality of this unique little windscreen washer pump.
After many long years of rebuilding my BN4 LongbridgeHealey, I finally got to the unique little windscreen washer pump that was notworking after 30 years of stagnation. On stripping the unit, I discovered, asmany before me also have, that the diaphragm had hardened and was completelyperished. Many nights were spent contemplating a fix for this as I wished toretain originality in looks and functionality, i.e. a mechanical pump utilisingthe same body and external features.
My first thought was to replace the diaphragm with the cutoff middle finger of a latex glove, stretched over the brass end plate andcomplete with the small internal spring, which was still in good condition.This trial worked reasonably well, but I was concerned that the stretched areawould soon perish and not last the distance. Back to regular contemplation overmany nights!
I then had a Eureka! moment and decided to try the humblelittle squash ball! See pics attached.
This is the procedure I used:
- Cut off approximately one quarter of the balland trim/grind the edge as flat as possible.
- Turn the ball inside out and place over amandrel to allow a 1mm wide groove to be machined/ground into the inside faceof the ball, approximately 1.5mm deep and 3mm from the cut edge.
- Reduce the diameter of the brass end plate to36mm.
- Reduce the diameter of the aluminium Plungerplate that makes contact with the diaphragm, by about 1mm.
- The use of the internal spring is optional asthe squash ball alone works a treat, but if you use the spring, reduce thediameter of the largest two coils of the spring to allow it to fit inside thesquash ball.
- Assemble the diaphragm onto the brass end plateusing silicone sealant in the groove.
- Insert the Plunger shaft into the body, followedby the squash ball assembly into the aluminium body.
- Seal the squash ball assembly into the bodyusing silicone sealant and bend over the aluminium edge of the body to hold inplace.
I hope this helps those who wish to retain mechanicalfunctionality of this unique little windscreen washer pump.
Attachments
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1. Dismantled.jpg87.9 KB · Views: 174
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2. Old Diaphragm.jpg88.9 KB · Views: 174
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3. End Plate.jpg98.4 KB · Views: 167
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4. End Plate Reduced Diameter.jpg112.4 KB · Views: 172
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5. Squash Ball.jpg68.5 KB · Views: 171
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6. Squash Ball Trimmed.jpg31.7 KB · Views: 165
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7 Squash Ball Trimmed.jpg33.6 KB · Views: 166
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8. Squash Ball Inside Out with Machined Groove.jpg39 KB · Views: 134
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9. Plunger Diameter Reduced.jpg30.9 KB · Views: 173
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10. EndPlate Inserted into Squash Ball.jpg37.4 KB · Views: 128
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11. Silicone Sealed.jpg48.7 KB · Views: 166