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parkerman
01-24-2005, 06:51 PM
I have a 62 hawk GT with auto transmission. When I bought the car, it had a bad transmission leak. It looked like it was coming from the front seal. I took it out and replaced the front and rear seals, pan gasket, and o-rings for the gear selector shafts. It still leaks.

One thing I noticed is that the original front seal was a much thicker seal. It looked like a modern seal, with the rubber lip, and spring on the inside, but it also had a thick felt washer inside. I took it to a local parts store, who was able to cross reference it to a modern type seal. I have now replaced the front seal four times, each time with the same type of modern design seal. I ordered two of them from SASCO.

An old time mechanic friend suggested that the transmission might have a drain hole near the front seal, where the fluid is supposed to drain back into the housing, and that the hole might be blocked. I am thinking the old seal, with the felt washer might have prevented some of the leakage.

Does anyone have experience with this? Any ideas? Does anyone know where I can get the original type front seal?

Dave Parker
parker@cafes.net

Sonny
01-24-2005, 07:09 PM
I dunno Dan, that sounds like a hell of a PITA, pulling the tranny and replacing that seal 4 times has to qualify you as a master Studebaker tranny technician! :) What I'm thinking is torque converter too. The seal rides and wears on that torque converter coupling. Have you mic'ed the coupling? It could have been "on the low line", (diameter size wise), when it was new, add years of seal wear and you have a leak no matter what seal you use. Just a thought....

Oh, and just thought about this... Is it in perfect alignment? Mebbe you could check the bellhousing alignment runout too.

Sonny
http://RacingStudebakers.com

buddymander
01-24-2005, 07:43 PM
there's a large lathe-cut o-ring around the outer edge of the pump. They get old and brittle and shrink. Sometimes you can use something like Trans-X to swell it back up. You didn't mention if it leaked while running or off. Sometimes a worn pump bushing can cause an overnight leak. If it's intermittent, then that means that the pump bushing has worn into the torque converter on one side, causing it to leak only when the worn bushing area coincides with the worn converter area.

BJsHawk
01-25-2005, 10:16 AM
I have been told that there is a "case vent" somewhere on the transmission that will cause fluid to leak under certain conditions. I haven't found the vent so I am not sure that it exists. I have a 63 Hawk and my transmission leaks intermittenly when hot. It looks like it is coming from the right front but I haven't been able to pin point it. Have you been able to locate a case vent?



quote:Originally posted by parkerman

I have a 62 hawk GT with auto transmission. When I bought the car, it had a bad transmission leak. It looked like it was coming from the front seal. I took it out and replaced the front and rear seals, pan gasket, and o-rings for the gear selector shafts. It still leaks.

One thing I noticed is that the original front seal was a much thicker seal. It looked like a modern seal, with the rubber lip, and spring on the inside, but it also had a thick felt washer inside. I took it to a local parts store, who was able to cross reference it to a modern type seal. I have now replaced the front seal four times, each time with the same type of modern design seal. I ordered two of them from SASCO.

An old time mechanic friend suggested that the transmission might have a drain hole near the front seal, where the fluid is supposed to drain back into the housing, and that the hole might be blocked. I am thinking the old seal, with the felt washer might have prevented some of the leakage.

Does anyone have experience with this? Any ideas? Does anyone know where I can get the original type front seal?

Dave Parker
parker@cafes.net

parkerman
02-01-2005, 07:09 PM
Sorry for taking so long to reply.

In response to the "case vent", there is a case vent on the upper right front of the tranny case. It has a small cap type cover that rotates. You can easily reach it with your hand, while under the car. I could not detect a leak coming from that location.

I did think about the sizing of the torque converter coupling. There is a shiny spot where the seal rubs, but I could not detect any real wear by touch. I would have to borrow a micrometer to check it, but how much wear would be acceptable? Is there a specification for the diameter of the coupling?

The idea of checking the alignment of the torque converter occured to me too, but I was not really sure how to check it. I guess I could borrow a dial indicator and set it up to check the run out. But if it is out, how do you adjust it? If I have to take the bell housing off to make adjustment, wouldn't that cause a misalignment when the transmission is re-attached? The transmission lines-up pretty nicely with the shaft and the four attaching bolts. Seems like there should be some alignment pins, but there is not any.

The transmission leaks when it gets warm, usually leaves a trail of small drops. But when you park it after driving it, it will leak about a pint overnight. The above ideas sound good, but I am still wondering about the thickness of the old seal compared to the replacement seal. Right now, I have the car put back together and have been driving it some. It drives and shifts OK, but the leak is a bother.

Dave Parker

Roscomacaw
02-01-2005, 08:57 PM
Dave,
You've touched upon a point that stymies many Big 3 enthusiasts. Every Stude engine had it's particular bellhousing individually (uniquely) aligned to it! I know that sounds goofy, but that's how it is. Consequently, if you change an engine and don't also change to the bellhousing that said engine was mated to - from the factory - you MUST check the runout of the tranny hole in the B/H with respect to the crankshaft.
I don't know that such misalignment would cause the woes you talk about but I DO know that it'll ruin the flex plate that mounts the torque convertor to the crankshaft over time.[V]
The way to correct this is to use a dial indicator affixed to the crank so that the tip of the indicator rides on the ID of the tranny hole in the B/H. With the original alignment pins removed and the B/H snugged in place, you check the runout and use a hammer to adjust the B/H's position until the runout's within tolerance. Then you tighten the bolts and drill new holes for alignment pins![xx(]

Miscreant at large.

Sonny
02-02-2005, 01:14 AM
NP on how long it took to answer Dave, I know that we're all busy. Lemme answer what I can here...

Dave said: **I did think about the sizing of the torque converter coupling. There is a shiny spot where the seal rubs, but I could not detect any real wear by touch. I would have to borrow a micrometer to check it, but how much wear would be acceptable? Is there a specification for the diameter of the coupling?**

The shiny spot denotes wear for sure. I don't know where a fella could find the specs for the coupling dimension, but I'll bet it's in some obscure publication somewhere. It would be something to know for all of us. Wear in that particular area isn't usually a common problem, but it has been a problem for some of us none the less. What I would do is get that micrometer anyway and measure various places along the coupling, see how much wear there is at the shiny spot. Also, mebbe you can talk someone who has a tranny sitting around to check theirs too. That might give you some idea about how much wear you're up against there.

**The idea of checking the alignment of the torque converter occurred to me too, but I was not really sure how to check it. I guess I could borrow a dial indicator and set it up to check the run out. But if it is out, how do you adjust it? If I have to take the bell housing off to make adjustment, wouldn't that cause a misalignment when the transmission is re-attached? The transmission lines-up pretty nicely with the shaft and the four attaching bolts. Seems like there should be some alignment pins, but there is not any.**

As Bob was saying, that run out MUST be checked and I think he pretty much explained how to do it. If you didn't find ANY alignment pins, that's trouble for sure. You MUST have 2 alignment pins, lightly interference fit into the engine block. It Does take a special
"fixture" that provides a solid base for the dial indicator to attach easily and work correctly. There are fellas around here who have them and I'm sure someone would loan one to you. In fact, I posted a couple pictures of what the setup looks like here for ya. http://racingstudebakers.com/coppermine/albums/userpics/10001/normal_bellhsngdialtool1.jpg If you're handy at all, you can see that the mount doesn't have to be real fancy.

**The transmission leaks when it gets warm, usually leaves a trail of small drops. But when you park it after driving it, it will leak about a pint overnight. The above ideas sound good, but I am still wondering about the thickness of the old seal compared to the replacement seal. Right now, I have the car put back together and have been driving it some. It drives and shifts OK, but the leak is a bother.**

Not to step on any toes, but I think that the bellhousing being off enough could cause a leak. Meaning, the bellhousing being out of perfect alignment forces the transmission to hold pressure via the coupling on the converter in a "tweaked" or "pre-loaded stress condition", that eventually will crack and/or break the flywheel. That's a known problem that has plagued our cars. Then obviously, if the converter is "cranked" out of alignment with the transmission, the seal which is mounted in the transmission is hitting the coupling off center, rubbing the coupling unevenly. Instead of controlled, even seal pressure on the coupling, the place where the seal is applying high, uneven pressure, (pressure point), accelerates the wear in the seal and the on coupling itself at the pressure point. OR, (if it leaks just while running), a seal works properly by having oil pressure behind the rubber cup, expanding the seal outward, applying even pressure against the rotating coupling. If the coupling is canted or off center, it's possible for the seal to leak on the "off-pressure" or "light" side of the seal by the fluid under pressure "lifting" and escaping under the "light" pressured portion of the seal.

One thing to remember, although the transmission