Leaking Hughes Deep Pan

1KWIKSIX

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Joined
Sep 29, 2007
I am experiencing a very small leak since installing this deep aluminum pan. Seems to be originating (for the most part) from the left front corner (drivers side) gasket / sealing area. I've even removed the pan once & installed a new fibre gasket & ensured the bolts were snugged down in a criss cross pattern. Also appears that some of the allen bolts holding the pan have very small amount of transmission fluid on them. Do any of these bolts require some sort of sealer to prevent leakage?
Any one else experienced this problem?

I'd appreciate any insight or comments to resolve this issue.

thanks

dave
 
I had this happen with the deep sheet metal aluminum pan. 3 or 4 bolts from the front drivers side to the shift bracket bolts. I removed just those bolts individually and cleaned the bolt and pan with brake cleaner the re-installed the bolt with ultra black RTV on the threads. Try to be quick after cleaning the pan with the bolt or fluid may contaminate the process. I have had no leaks at all with this method. Make sure your shift bracket is not touching the pan and binding up the bolt sealing surface, I believe I have washers under mine.
 
Thanks for the suggestions. Just so I understand correctly, you have installed washers between the bracket & the pan?
Can anyone confirm if I'll have to drain the pan before pulling any bolts to install teflon paste / sealer ?
 
My Hughes pan has leaked since I installed mine as well. I have had to re-tighten the Allen head bolts numerous times and changed to the fiber gasket. The motor is out currently, but I would like a tip on getting it to stop leaking also.

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The 2 bolts on the driver side that hold the shifter linkage need to have thread sealent on them.
 
I've now dumped the transmission fluid & removed the pan. Noticed some very slight weeping from around the "O" ring on the electrical pass thru connector on the side of the transmission. I do have a new replacement that will be installed. The seal on the shifter shaft appears to be dry, so will leave that alone (at this time).
Have pulled the convertor inspection cover & convertor is dry & so is inside the metal cover, so no issues going on there!
TV cable grommett is dry & obviously sealing well, so nothing to worry about on that side either.
I am going to have the Hughes Pan checked for warpage too, as the left front (drivers) area where gasket meets transmission is definitely a wet area. I did have the pan powder coated black after I bought it & it may have warped from the heat in the oven?
Don't really want to & I shouldn't need to use "the right stuff" or Permatex "Ultra Black" on the gasket / pan as it will be very difficult to remove the pan afterwards. However, I may apply a small amount only in the left (drivers side) corner area where the leak seems to be originating from.
Thanks to those who suggested applying a sealant to the threads of the two bolts holding the shift cable bracket. I will be sure to apply some sealant (teflon paste or Permatex "ultra black") to these threads on the two bolts on re-assembly.

Any other thoughts or suggestions would be welcomed.

thanks

dave
 
Installed a Hughes pan last summer, it's as dry as a chip under there. Just installed gasket supplied with no silicone.
 
I would check above the pan rail. 9 out of 10 times the leak is above the pan rail


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I would check above the pan rail. 9 out of 10 times the leak is above the pan rail


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Yup, will do....that's what I was thinking too!

I don't have a machinists straight edge or level, so would placing it on a flat sheet of plate glass reveal any high spots?
 
Yup, will do....that's what I was thinking too!

I don't have a machinists straight edge or level, so would placing it on a flat sheet of plate glass reveal any high spots?
I meant the servo, shaft seal, connector, tv grommet, dipstick grommet, speedo bullet, vent, etc. Your pan could be way off and still seal with the gasket. The Hughes pan is cast. It's not easily going to get tweaked without taking a hard impact. I've seen plenty of bent to hell pans still seal when torqued down.


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I wouldnt use silicone on threads going into aluminum I once used it on valve cover bolts and it got squished in the bolt hole with nowhere to go and broke off two bosses on my aluminum head.... I wasnt reefing on it either

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I wouldnt use silicone on threads going into aluminum I once used it on valve cover bolts and it got squished in the bolt hole with nowhere to go and broke off two bosses on my aluminum head.... I wasnt reefing on it either

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Threads on the side rail of the transmission go through the case, no chance of stripping any bolts unless you over tighten them.

I did not have to drain of remove my pan just sealer on the bracket bolts and the one in front. The reason for the washers under the bracket was clearance to the weld bead, you probably don't have this problem as your pan is cast.
 
When I checked the pan for warpage by sliding a feeler gauge under the cover when placed on a flat sheet of glass, I found the left front corner was approximately 0.005" lower then the rest of the pan. The gasket I removed verified the trouble spots as the area was smooth & no evidence of being compressed like the rest of the gasket.
Thought that a new Farpak gasket + a light smear of Permatex Ultra Black on both side of the Farpak transmission pan gasket should fix it. After all 0.005" is not much more than the thickness of a sheet of paper.

Well, after installed the cover & carefully torquing it down, have found that it is still leaking from the same spot.

Hmmmm.......guess the next step will be to take the pan off again & have it milled flat at a machine shop & try it again?

I'll post pictures of the witness marks left on the used tranny pan gasket I removed.

Any other suggestions or comments would be appreciated.

thanks in advance.

dave
 
Did you use the Permatex transmission RTV?
 
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When I checked the pan for warpage by sliding a feeler gauge under the cover when placed on a flat sheet of glass, I found the left front corner was approximately 0.005" lower then the rest of the pan. The gasket I removed verified the trouble spots as the area was smooth & no evidence of being compressed like the rest of the gasket.
Thought that a new Farpak gasket + a light smear of Permatex Ultra Black on both side of the Farpak transmission pan gasket should fix it. After all 0.005" is not much more than the thickness of a sheet of paper.

Well, after installed the cover & carefully torquing it down, have found that it is still leaking from the same spot.

Hmmmm.......guess the next step will be to take the pan off again & have it milled flat at a machine shop & try it again?

I'll post pictures of the witness marks left on the used tranny pan gasket I removed.

Any other suggestions or comments would be appreciated.

thanks in advance.

dave


Nope, I couldn't find that particular one, I searched for it but was told it is discontinued & no longer available in Canada, so I used Permatex Ultra Black, which should work OK (or so I was told by a leading 200-4R Transmission Specialist).
 
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Update:
Well, I believe I've finally discovered the source of my problem. I installed some UV dye in the transmission fluid & started the car up. With my yellow tinted glasses on & using a black light I could see a slight drop of fluid forming around the brand new electrical pass thru connector . Seems that since the front of the transmission sits lower than the back, gravity was directing the drips to the front Left (drivers side of the transmission pan).
Hmmm....this was a brand new pass thru connector that I bought from Dennis & had a new "O'" ring on it too! Damn it! Guess I should have applied a generous amount of Permatex Ultra Black around the "O" ring before I installed it.

Has anyone else had a leaky pass thru connector? Wonder if there's any way to seal it up without draining the fluid & dropping the pan (again)?
 
drained the oil & dropped the pan last night (again)......this time I applied a generous dollop of Permatex "Ultra Black" to the "O" ring area on the electrical pass thru connector (& a thin skin of Ultra Black on both sides of the pan gskt).
Hooray!
Looks like the leaks are gone! (touch wood).

Bison....you were right....the leak was coming from above the pan rail area.

I must have had the stupid pan off 3 or 4 times before getting the leak figured out.

No leaks this morning & have taken it out for a drive today & seems to be holding. :)
 
Congratulation, you finally found and repaired the little bastard leak that was giving you some grief.
I know the feeling of dropping the pan down 3 times since I too had a small leak at one time and it drove me crazy trying to find the little bastard.
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I don't have a machinists straight edge or level, so would placing it on a flat sheet of plate glass reveal any high spots?
Glass is made by pouring it liquid floating on a pool of mercury - very flat!
I have used a 12" mirror tile and a nice piece of 1/4" tempered scrap as the flat surface for working the scratches out of oil pump covers* and fine-tuning end clearance when I had more time than money. Can wear your arms out swirling over wet-n-dray sandpiper + lubricant but got excellent results with straight edge to check straightness and feeler gauge to check gear clearance.

*not Buick motors
 
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