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OD question

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The isolation switch is mounted on the transmission itself, out of view. It keeps the overdrive from engaging in reverse, first and second gears. If it is working, there is no reason to worry whether or not you forgot to switch out of overdrive.

However if this switch fails, you can cause serious damage to the overdrive unit by driving in reverse. You can also cause damage by accelerating too hard in first or second gear with overdrive engaged. This is why the switch is there, to prevent such damage.

It is good practice to manually switch off the overdrive as a backup to the switch. If the switch fails, this will save the overdrive unit.

The easiest way to test the switch is as Ric suggests. Drive in second gear, flip the overdrive on and see what happens. If no change, the switch is working and you have no worries.

You can also install an overdrive lamp in the dash to help remind you when it is on and off. It is not stock so a little creative wiring is in order, but it can be done. I have one in my GT and I love it.
 
I never could understand why an indicator light was never installed by the factory, to tell you it was in or out of OD. That could be another little project for someone along with the reverse lockout switch. /ubbthreads/images/graemlins/rolleyes.gif Hmmmmm?? PJ
 
I've seen a couple ODs that have had the connectors going to the isolation switch pop off, or have broken wires. Both act the same as a bad switch.
 
Makes the five speed Rivergate conversion REALLY enticing, doesn't it?!

/ubbthreads/images/graemlins/smile.gif
 
A reverse lock out switch! YES, that's the thing the guy in our club has made. And it works.

I'd let someone try something like that on my cars. DCO or DCF (desperate current friend) whatever.

I didn't get an opportunity to drive the car last night, nor will I today until early evening when we leave for the British Invasion at Steak & Shake. But I'll report back.
 
Reverse lockout is an intresting concept. Would like to see how that was done. Not that I need one, just intresting.
 
[ QUOTE ]
A reverse lock out switch! YES, that's the thing the guy in our club has made. And it works.

[/ QUOTE ]

But, the question remains: WHY??

[ QUOTE ]
I'd let someone try something like that on my cars. DCO or DCF (desperate current friend) whatever.

[/ QUOTE ]

I wouldn't - while he might be a fine electrical engineer - just the fact that he built a "third wheel for a bicycle" (because that's all his gizmo is) doesn't mean he knows anything about MG's...which apparently he doesn't because he built something that's already on the car!

Just check to see if your OD Isolation Switch is working....if its not, spend the $12.00 or so to buy a new one, screw it into the side of the transmission & hook up the wires!



The car already has one - & I'll say it again, it's called an OD Isolation Switch....it locks the OD out of being able to operate in 1st, 2nd, &, yes, reverse.

....you already have one Janel!
 
Bob has built several engines, restored several cars. The man knows as much, if not more, about MGs than the average person. And 100x more about electronics.

I know I have an OD isolation switch. The question is to see if it is functioning properly. Once that's determined then I can either pull the engine and tranny and replace it, or talk to Bob about the lock out.

Tony, you make me laugh. You and I wouldn't last a full 24 hours together without coming to blows I do believe.
/ubbthreads/images/graemlins/devilgrin.gif
 
[ QUOTE ]
Tony, you make me laugh. You and I wouldn't last a full 24 hours together without coming to blows I do believe.

[/ QUOTE ]

Possibly - possible not...I just don't see putting bandaids on problems..that's what his homemade switch is - a bandaid.

I figure if it needs broken, fix it properly the first time because I definitely don't have time to go back & fix a bandaid.

If someone comes up with an improvement over what the factory designed, that's one thing - but to reinvent the wheel for no reason???....think about it, Janel: that factory OD Isolation Switch has probably worked properly for at least 30 years...if its now finally given up, for a few bucks, you can have another 30 years of peace.

But, you're asking for solutions before ewe know there's a problem!

Oh, & everyday I disassemble little dead cars that somebody who knew what they were doing repaired/fixed/restored in their own way.
 
But Tony, my dear man, that doesn't mean that for every car you DISassemble, there aren't a dozen, a hundred, more, that are done correctly. WITH improvements.

I wouldn't look at this as a bandage. (not BandAid, I prefer Curad) I would look at it as an improvement. And we all know that many people have improved upon MGs and their workings in the last ooooh, 60-70 years.

If a reverse lock out switch would improve on the current isolation switch, I'm all for it.

And when I decide to let Bob 'experiment' with my new car, I'll be sure to let you know how it works. Or doesn't. I do have a spare working engine and overdrive sitting in the garage.

/ubbthreads/images/graemlins/angel.gif
 
IFIN he is a "EE" he know what he is doing.---Keoke- /ubbthreads/images/graemlins/yesnod.gif
 
[ QUOTE ]

IFIN he is a "EE" he know what he is doing.---Keoke- /ubbthreads/images/graemlins/yesnod.gif

[/ QUOTE ]



Not the one's I work with. /ubbthreads/images/graemlins/frown.gif
 
Boy, I am glad that I am not in the middle of this one... /ubbthreads/images/graemlins/rolleyes.gif
 
There's no 'this one' here. Tony and I disagree on a lot of things. It's just friendly bantering while I try to figure out this OD issue.

Besides Tony (yea yea, I can't let it go) if no one had ever improved on the MG, we'd all be driving Old #1.
 
Janel - I'm all for improving an MG - but, you can't tell me that a switch that replicates the original is an improvement....about the only improvement the original switch needs is a light that tells you when the OD is engaged & when it is not....I'd bet that when it comes down to what he's done, he just made another OD Isolation Switch exactly like to old one because his died!

...&, Janel, the only way to figure out this OD issue is for you to go drive the car & see if your switch works...I gave you one option of how to check, you've had others presented also....until you do one or both, this is a mute point!

Then, after you drive the car, if you find yours doesn't work, you can put another factory switch in your car or let the EE build the same thing! & if the switch does work, we've all learned how OD's work! (Oh, how many times have any of us heard about somebody damaging their OD by shifting into reverse with the OD engaged? Zippo! Tells me the factory switch is doing what its supposed to do!)

I'm beginnig to think this thread is like a train wreck - its happening, its gonna continue to happen, there's nothing anybody can do about it, but we all want to watch it....the only difference in this one & some others is we can spell, punctuate, and make coherent statements. And we don't personally abuse one another!
 
~clasps hands over mouth, giggles~

Now I'm mute. Tony and I agree to disagree. No one else is coming near voicing their opinion in here.

I'm driving Binabox tonight. This entire thread could very well be moot if the OD switch works.
 
I guess I should have been mute and left my observation -- moot....
/ubbthreads/images/graemlins/smirk.gif
 
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