78 Lincoln C-6 tranny leak

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Silent Thunder
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78 Lincoln C-6 tranny leak

Post by Silent Thunder »

OK any ideas? I have a tranny that runs perfect. Noticed a leak under the car. Took it to my mechanic who pulled the tranny and replace the seal to the motor. Sat for a day, no leak. Took it home and it sat for one week. Pulled the car out and on my garage floor tranny fluid with about an 18" wet spot. Took it back ,tranny pulled same seal replaced and was told all other visable seals were dry. Sat for 48 hours no leak. Took it home and it sat for one week, pulled the car out and the wet spot all over again. The drip is not from the pan but in front of it mid way from the pan to the engine. I hate to rebuild the entire tranny. What gives??
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Re: 78 Lincoln C-6 tranny leak

Post by KULTULZ »

Silent Thunder wrote:
OK any ideas? I have a tranny that runs perfect. Noticed a leak under the car. Took it to my mechanic who pulled the tranny and replace the seal to the motor. Sat for a day, no leak. Took it home and it sat for one week. Pulled the car out and on my garage floor tranny fluid with about an 18" wet spot. Took it back ,tranny pulled same seal replaced and was told all other visable seals were dry. Sat for 48 hours no leak. Took it home and it sat for one week, pulled the car out and the wet spot all over again. The drip is not from the pan but in front of it mid way from the pan to the engine. I hate to rebuild the entire tranny. What gives??
You are saying the tech replaced the trans front seal? And the leak appears to be coming from about the middle of the transmission pan?

Image

It sounds like-

1) The fluid is coming from the filler tube base (O-Ring)

2) Servo cover

3) If the leak takes a few weeks to show, the torque convertor may be bad, draining its fluid back into the pan and out the filler tube or vent.
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Re: 78 Lincoln C-6 tranny leak

Post by Silent Thunder »

No not the middle of the tranny pan but rather in front of the pan (engine side) midway between the front edge of the pan and the engine or about 4 inches from the front of the tranny is where I would see the drip. I think your number 3 answer is correct. So I guess I should have the torque convertor replaced. Other than leaking how else would one know if they had a bad torque convertor? With a standard convertor (about $100.00) what should the total replacement cost be? $200.00??
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Re: 78 Lincoln C-6 tranny leak

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Silent Thunder wrote:
No not the middle of the tranny pan but rather in front of the pan (engine side) midway between the front edge of the pan and the engine or about 4 inches from the front of the tranny is where I would see the drip. I think your number 3 answer is correct. So I guess I should have the torque convertor replaced. Other than leaking how else would one know if they had a bad torque convertor? With a standard convertor (about $100.00) what should the total replacement cost be? $200.00??
You need to have it diagnosed by a reputable shop before spending any more money. There is an O-Ring where the filler tube goes into the case. That might be bad also.

A torque converter will fill itself up in just a moment or so. But its taking a few weeks to leak sounds like the torque converter. I assume he replaced the filter when he did the seal?
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Re: 78 Lincoln C-6 tranny leak

Post by Silent Thunder »

Yes and the pan is not leaking. Yes since it sits for a day or two and is bone dry then after a few more days it dumps. My 57 Chevy is dry all summer but over the winter does the same thing. Thought it was just the way it is. I did not know I could get the convetor changed and solve that problem.
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Re: 78 Lincoln C-6 tranny leak

Post by KULTULZ »

Silent Thunder wrote:
Yes and the pan is not leaking.
I was asking to find out if the filter itself could possibly be plugged.
Yes since it sits for a day or two and is bone dry then after a few more days it dumps. My 57 Chevy is dry all summer but over the winter does the same thing. Thought it was just the way it is. I did not know I could get the convetor changed and solve that problem.
The fluid drains from the converter and the pan has no capacity for the additional fluid so it seeks the first out.

Don't replace it just on my say-so.
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Re: 78 Lincoln C-6 tranny leak

Post by Silent Thunder »

I think it makes sense and I am willing to gamble it is correct for $200.00 I will try it. Why does the Torque convertor drop the fluid? Is there a vacuum leak because of a bad seal?
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Re: 78 Lincoln C-6 tranny leak

Post by Dan Szwarc »

What about the front pump seal?

Pull the inspection plate at the front of the trans and see if there is fluid inside the bellhousing.
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Re: 78 Lincoln C-6 tranny leak

Post by Silent Thunder »

I've had the tranny pulled twice, if there was fluid in the bell housing they would of seen it. They said all the seals visible from the pulled tranny look dry.
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Re: 78 Lincoln C-6 tranny leak

Post by KULTULZ »

Silent Thunder wrote:
I think it makes sense and I am willing to gamble it is correct for $200.00 I will try it.

Why does the Torque convertor drop the fluid? Is there a vacuum leak because of a bad seal?
There is a one way fill valve that may leak allowing the converter to drain. The converter itself may also be defective or ballooned. The support bushing may also be bad allowing wallowing of the front seal.

Let us know how it comes out.
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Re: 78 Lincoln C-6 tranny leak

Post by Dan Szwarc »

Took it to my mechanic who pulled the tranny and replace the seal to the motor.
I don't know what this means. There is no "seal to the motor".

I can't believe the tranny was removed twice and not rebuilt with a new torque converter at least one of those times.

It's like opening a guys chest for heart surgery and only looking around.

A simple leak at the filler tube is a new o-ring without removal. Easy to diagnose and to fix.

I think you need to find a new mechanic.
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Re: 78 Lincoln C-6 tranny leak

Post by sauceman »

I too have been dealing with a leaking pump seal...

Image

It used to drain about 4 litres of fluid in about 3 months, it think it was a drip every 30 seconds, pretty nasty leak.

BUT!

Two days ago I tried this snake oil...

Image

AND IT FRIGGIN WORKED!!!!!!!!!!!!!!!!!

Now i'm not a firm believer in these kinds of miracle cures, but I poop you not this product actually stopped the leak.

I realize that this is just a temp measure and when I pull the pack next year it will be sorted, but regardless this stuff worked for me!


cheers
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Re: 78 Lincoln C-6 tranny leak

Post by Silent Thunder »

And mine is in the tranny shop right now being fixed. Should pick her up in a day or two.
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Re: 78 Lincoln C-6 tranny leak

Post by Spot »

This "no leak" stuff just increases the viscosity of your fluid, that doesnt solve the problem.
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