oil pan/auto trans. oil pan bolts

[nwfire]

Happy New Year to all!  I have a hard time keeping my oil pan bolts and the bolts on the auto. trans. oil pan tight on my '67 GT500, #906.  Seems like 2 or 3 times a year I'm under the car tightening them.  My present oil pan bolts have the "captured" lock washer and the trans. oil pan bolts have the "hex washer" heads as per the AMK catalog nomenclature.  The AMK catalog shows a "Ford Oil Pan" bolt on page 97, bottom line, far left corner of the page.  This bolt has a "conical" captured washer.

I see in the NPD catalog, "concours" bolt kits for each of these application.  Page 185, item #7A194-2AK for the trans. bolts and page 144, item
#6675-4AK for the oil pan bolts.

Which of these options is correct?  Especially for the oil pan, captured lock washers or conical head captured.  And are the trans. pan bolts listed correct?  Anything special about them?

Thanks for any responses.

[Bob Gaines]

Happy New Year to all!  I have a hard time keeping my oil pan bolts and the bolts on the auto. trans. oil pan tight on my '67 GT500, #906.  Seems like 2 or 3 times a year I'm under the car tightening them.  My present oil pan bolts have the "captured" lock washer and the trans. oil pan bolts have the "hex washer" heads as per the AMK catalog nomenclature.  The AMK catalog shows a "Ford Oil Pan" bolt on page 97, bottom line, far left corner of the page.  This bolt has a "conical" captured washer.

I see in the NPD catalog, "concours" bolt kits for each of these application.  Page 185, item #7A194-2AK for the trans. bolts and page 144, item
#6675-4AK for the oil pan bolts.

Which of these options is correct?  Especially for the oil pan, captured lock washers or conical head captured.  And are the trans. pan bolts listed correct?  Anything special about them?

Thanks for any responses.

Having to tighten oilpan and trans bolts every so often is not out of the ordinary for your 67 Shelby. Heat cycles of the engine can cause the bolts to loosen over time . Of course you can use lock tight if it really bothers you but that was not used from the factory . The AMK bolt kits are the closest you will find short of reusing original. The AK at the end of the NPD catalog number denotes a AMK product. 

[pbf777]

Having to tighten oil pan and trans bolts every so often is not out of the ordinary............... Heat cycles of the engine can cause the bolts to loosen over time . Of course you can use lock tight if it really bothers you ...................

     Just to expand a little on this:  Yes, it is not unusual for these fasteners to loosen in time, but the initial loosening of the fastener has more to with heat cycling, with increased loading and then relaxation, and the resultant crush and shrinkage effects this imparts on the sealing gaskets, which then present a reduced fastener clamping load which then permits the fluid leakage event; and if not addressed, in time the fasteners' underhead preload will be lost adequately to 'then' permit vibration to shake the fastener out onto the ground.   

     So with this understanding, the use of a thread-locking compound to freeze the fastener in place, though it might keep one from loosing the fastener onto the pavement, won't prove to be an aid in controlling leakage, and as a matter of fact, will inhibit ones' ability in the ultimately required re-torquing task in order to keep things sealed up at a later date.    

    Oh, and don't choose to practice "over-torquing" these, no matter the frustration that accompanies the re-torquing requirements, as then you'll open a new "can of worms"!   

    These old cars, back then, leaked the day one brought it home new from the dealership; we can generally do better today at sealing them up then F.M.C. did originally, but still..................., it is unfortunately and not intentionally, by design to leak!   

    Scott.

[nwfire]

OK, thanks for those responses.  I think I'll try some new pan bolts and retorque.  I see 9-11 lbs. for the oil pan and 12 lbs. for the trans pan.  Sound correct??

[shelbydoug]

I personally think that the issue with the bolts loosening on the oil pan is caused by using a cork gasket?
Those things compress over time and that right there can cause loose bolts.

[OldGuy]

I personally think that the issue with the bolts loosening on the oil pan is caused by using a cork gasket?
Those things compress over time and that right there can cause loose bolts.

Doug is spot on! Cork compresses and rubber creeps causing the symptoms that the OP described. If one over tightens sheet metal engine oil or trans pan bolts, it distorts the pan sealing surface and causes increased oil leakage. There are non-stock band aid fixes (doublers) that can lessen the effects but once the pans are distorted leaks (seepage) will ensue.

Frank

[Bob Gaines]

OK, thanks for those responses.  I think I'll try some new pan bolts and retorque.  I see 9-11 lbs. for the oil pan and 12 lbs. for the trans pan.  Sound correct??

Yes.

[J_Speegle]

Sorry for showing up late but have had some distractions

Here are some close up of the two items you ask about

67 - Engine oil pan bolts




67 - C6 oil pan bolts