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Overdrive Operating valve bent


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Popped a freshly rebuilt tranny and OD unit into the 100 and the OD is not working. Check all the electrical stuff and adjusted the solenoid lever using a drill bit to align the hole, etc. but still not working. Took out the operating valve to make sure the pump is working and to check that the weep hole is clear and it turns out the operating valve is bent! How did that happen? I can get a new valve at the place in California but now I'm concerned that something else might be amiss inside the unit. Can the operating valve get bent if the wrong assembly sequence was used? Any thoughts on this?
Possily an oversight and possibly the wrong part. I have not experienced that failure. However, I would replace the valve on the premise that would be the simplest possible corection for me.
Thanks, Keoke. I'm going to take the pump out also to make sure it's in order. Hope it's as simple as a new operating valve.
Thanks, Keoke. I'm going to take the pump out also to make sure it's in order. Hope it's as simple as a new operating valve.

See if "Mr Finespanners" instructions covering the pump can be located on the webb it may have been taken down with his demise.
Lucky I saved it some time ago ...


  • Del Border (Mr Finespanner) The Overdrive.pdf
    195.4 KB · Views: 111
One of those telescopic magnet antenna thingies works as well for removing the valve rod piece .
Thank you, Big Green, excellent article.

I'm having a hard time getting the pump out and leaving town for a bit but I'll keep you all posted how this progresses when I get back.
Sorry if this isn't the best way to post a link but if you go to this BCF thread from a while back you can see that I had multiple issues with the the transmission oil pump in my BN2. https://www.britishcarforum.com/bcf...my-overdrive-with-a-saws-all&highlight=roscoe

My car was in pieces when I bought it but what I could see inside the gearbox was pristine and I didn't find all this stuff out until I "finished" my restoration and had it on the road. Putting it on SECURE jack stands made the troubleshooting way easier and a pressure gage is a must if you have done everything you can and it still doesn't work. The bent/ jammed oil pump was a surprise. I can't imagine what would cause the operating valve to bend as the only force on it is from the solenoid engaging and I would guess that is not enough to bend it even if it were badly mis-rigged. Did it move up and down freely and slide out easily?
Thanks, Jon. The operating valve came out relatively easy and why it's bent is a mystery. I need to get the correct pressure gauge and make a better puller to get the oil pump out. I want to inspect all the parts I can reasonably get out before putting everything together. The articles everyone has posted are a huge help. Thanks.
Where in CA are you. I'm near Davis and I have a puller and a gage.
Jon, I'm in Burlingame. Thank you for the offer, let me see if I can get the pump out with my revised home-made tool. If not, I'll take you up on your offer.
I pulled my pump out with a slide-hammer...






Whole sequence of removal (including making the adapter...) starts at the bottom of this page: https://spcarsplus.com/gallery3/index.php/Healey-at-home/gearbox_work?page=8
OH!! Man that is :cool:--Randy
I thought about the slide hammer technology but the issue is I'm doing this with the unit in the car which limits the height under the car to jack stand dimensions so I need to use more of a "puller" approach vs. a dynamic impact approach.

Randy, please accept this as a note of thanks for all the help you have provided to me and others on this forum. Your contributions are invaluable. Thank you.
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