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OD trouble looming?

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nevets

nevets

Jedi Knight
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Took the mighty Healey out for a spin last Sunday and the first couple of times I flipped the OD switch, there was no response. After a few minutes, it started working normally. Perhaps things needed to warm up a bit, revs too low, or is this an early warning sign of a more serious problem? Any thoughts would be appreciated, thanks.
 
Since the OD operating pump is driven from the output shaft, it doesn't pump until the car is actually moving. It could take a little while to build pressure if everything is not in perfect condition. The problems could range from leaking accumulator seals to mis adjusted or leaking operating valve, to general wear or low on oil. Or, the oil could be a little thick for your temperatures. Many folks use a 20W-50 motor oil with good results.

I would make sure that it is filled with the correct oil & wait to see what develops.
D
 
Thanks Dave
I will check oil level. I've owned the car for a little over 10 years with no OD problems to date (touch wood) and I am assuming that the leaking seals you mention would result in telltail puddles on the garage floor, which I have not seen? It was a rather chilly day, temps in the low 50s, perhaps it's a viscosity issue? Anyway, I'll follow your advice, check oil level and take a "wait and see" approach.
 
The accumulator I mentioned is a spring loaded piston inside the OD. It "stores" oil under pressure to provide for quick OD shifting when quick oil flow is needed. The piston has seals, much like piston rings. If they leak, operating pressure could be slow to build up. It wouldn't show up as an external leak. If needed, the seal rings could be replaced from the outside without completely disassembling the OD.

Another possibility is that the solenoid operated control valve is marginally out of adjustment. The "factory" adjustment procedure of lining up the lever with a pin is not very accurate after the parts have some age & wear. I could give you a better, more accurate method of setting this lever if you wish.
D
 
Dave, it Could also be a spot of dirt or a tired spring on the one way return valve.---Keoke
 
Hi Keoke,
Yes - It could be. I have found several little modifications that can improve shift speed/reliability. One of them involves increasing the non return valve's spring follower by about .100" in length to give more reliable seating/sealing of this ball valve. I didn't mention it at this time because getting the brass cap plug unscrewed inside the box can be a bit of a war. I don't know how far nevets wants to get into this project.
D
 
Thanks Keoke and Dave for your thoughts
Contrary to my gut and past experiences with car problems, I am hoping that this was a temporary anomoly and that things will be fine once again. I neglected to mention that the car often goes 2-3 weeks or more without being driven, so perhaps things got a little stiff from inactivity...not unlike its current owner. If the problem persists, I will come back to the well for more help. As always, I appreciate your thoughtful input.
 
Dave/Keoke
Well I drove the car yesterday and once again there was no initial response when I switched OD, and as before, after several tries and a few more miles, it started working fine and continued working fine. Pray tell wise ones, what should I check into first (and how) in attampting to sort out the problem. Thanks
 
Well Nevets, it appears that your unit is having a bit of problem initially building up pressure.So you might try the operating valve adjustment that Dave provided earlier and see if it helps.---Keoke
 
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