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Misc Questions re Overdrive and Exhaust + Up-date on Redline Oil

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Misc Questions re Overdrive and Exhaust + Update on Redline Oil

Two quick questions:

Why is it detrimental for a 59 BT7 to back up with the overdrive button engaged?

Second, Is there any problem if my exhaust puts out some soot upon startup. It runs perfectly
but when we pull it in to the garage so that the exhaust pipe is up against the wall, we've noticed that it leaves some carbon on the wall.

Lastly, I had made a post some weeks ago about Tranny Noise in first gear. It turns out there was a broken tooth that needed to be removed. We added Redline MT 90 and the combination of doing both things has reduced the whirring in first gear to where it sounds very normal

Thanks for the help

Will Harrison
 
Re: Misc Questions re Overdrive and Exhaust + Update on Redline Oil

Hi Will,

Others will correct me if I'm wrong but I believe it has to do with the planetary gear set-up of the OD. It "overdrives" the annular gear but will jam if you try to reverse it. That's why it is so important that the switch on the transmission that only allows the OD to engage in 3rd and 4th is so important. If the switch is working you don't need to worry about turning the OD off. The OD will be off for reverse, 1st and 2nd but that shift into 3rd will actuate it again (and you will feel stupid for forgetting to turn it off because the engine bogs down so much).

Soot ... mine spews out moisture and black bits on start up. I think it has to do with lack of pollution controls
wink.gif
I wouldn't worry about it at all.

What exactly did you do for the broken tooth? Replace the whole gear or just fix the tooth? Glad to hear the Redline worked for you too.

cheers.gif
John
 
Re: Misc Questions re Overdrive and Exhaust + Update on Redline Oil

I believe the broken tooth was merely removed. The gear was not replaced. I am a lightweight and unfortunately do not have the confidence to learn to work on them just yet. I will ask the mechanic exactly what he did there.

Can I infer from your response that if the overdrive switch is on and I back up that I will not damage the overdrive? It would be nice if the answer is yes.

Thanks

Will
 
Re: Misc Questions re Overdrive and Exhaust + Update on Redline Oil

Yes, the limit switch on the transmission housing is there to prevent the overdrive from engaging in the lower gears and reverse, preventing damage. A quick way to test the limit switch is to turn on the ignition key and flip the overdrive switch to on ... then with the gear shift in neutral, rock the lever side to side. Each time you rock it past center you should hear the OD solenoid click on or off.

cheers.gif
John

[ 09-12-2002: Message edited by: John Loftus ]</p>
 
Re: Misc Questions re Overdrive and Exhaust + Update on Redline Oil

<blockquote><font size="1" face="Verdana, Arial">quote:</font><hr>Originally posted by will the thrill:
Can I infer from your response that if the overdrive switch is on and I back up that I will not damage the overdrive? It would be nice if the answer is yes.<hr></blockquote>

The transmission switch will, hopefully, keep you from backing up in overdrive. For a while, mine would not come out of overdrive; it was stuck mechanically. I didn't realize it at first, but if it's in overdrive when you back up, you will hear some VERY DISTURBING
frown.gif
noises. If you didn't hear any, you're safe.

cheers.gif

John
 
Re: Misc Questions re Overdrive and Exhaust + Update on Redline Oil

Originally posted by will the thrill:
Second, Is there any problem if my exhaust puts out some soot upon startup. It runs perfectly
but when we pull it in to the garage so that the exhaust pipe is up against the wall, we've noticed that it leaves some carbon on the wall.
It's because the mixture is rich on startup, giving some soot. When the tail pipe turns up, you get water condensation in the pipe and the exhaust flow picks it up, along with the soot and blows it out. It's nothing to worry about unless you stand behind the car with white trousers (it doesn't show on jeans). I now have side exhaust and the condensation just drips out.


cheers.gif

John
Click to expand...
Click to expand...
 
Re: Misc Questions re Overdrive and Exhaust + Update on Redline Oil

John and John

Thank you for your feedback. I will test the overdrive to see if the transmission switch works

Many Thanks

Will
 
Re: Misc Questions re Overdrive and Exhaust + Update on Redline Oil

The overdrive planatary gear function will, on engagement, work either way - clockwise to drive the car forward, or anticlockwise in reverse direction. There is a one-way roller clutch inside the final drive drum to ensure the planatary gear function turns clockwise to propel the vehicle forward. This function only works when the overdrive is engaged. In direct or non-overdrive position this one way clutch is non functional thus you can engage reverse. If the overdrive stays engaged and you select reverse your looking at a complete transmission teardown to replace a $800.00 shaft [if you can find one].

Regards, Bob
 
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