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Healey Overdrive Accumulator Piston using O-Ring Seal Up-date Feedback

mwagon

Jedi Hopeful
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Healey Overdrive Accumulator Piston using O-Ring Seal Update Feedback

In the process of rebuilding the O/D & noticed that AH Spares offers an updated Accumulator & Piston that uses a Rubber O-Ring on the Pistion, instead of the original design that uses a metal Pistion Rings. I don't see any other supplier selling this yet, but wondered if anyone has tryed this setup yet. I like the idea of eliminating the metal Piston Rings. The originals last a long time , but steel rings on an Alu. Accumulator never seemed right to me. Seems like it would minimze wear on the accumulator, similar to the Operating Piston arrangement
 
Re: Healey Overdrive Accumulator Piston using O-Ring Seal Update Feedback

I could be mistaken (it happens...) but seems like the later Healeys, certainly the units fitted to MGBs had switched from cast-steel rings to rubber O-rings, so you really won't be blazing a trail__which is to say that they're proven/accepted.

Likewise, the operating pistons on the later Healeys (and ALL MGBs, regardless of ovd type) used O-rings too, if you're so inclined to swap out these pistons.

Not to mention, the O-rings cost a minute amount compared to the cast rings!
 
Re: Healey Overdrive Accumulator Piston using O-Ring Seal Update Feedback

[edit- updated info, thanks Randy.]

I left mine as-is on the basis that the accumulator piston is also the pressure regulation valve and I felt that having an oring constantly crossing over the spill ports at 400-odd psi would shorten it's life greatly. The later design with oring seal used different size holes for the spill ports I think. Definitely good to replace the apply piston rings with orings. Andy.
 
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Re: Healey Overdrive Accumulator Piston using O-Ring Seal Update Feedback

Steel piston

IMG_3015.jpg


IMG_3017.jpg


Aluminum sleeve

IMG_3029.jpg


IMG_3033.jpg


IMG_3034.jpg


IMG_3037.jpg
 
Re: Healey Overdrive Accumulator Piston using O-Ring Seal Update Feedback

The same pieces, save for new cast rings and O-rings, but with a dry-film polymer coating added.

IMG_7110.jpg
 
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