Stripped Columbia house

Erbleding

Member
Hello all,

Still sorting out little issues with my newly acquired 36 Sedan Convertible and I have a new question. This car has sat for about 9 years as far as I can tell, after a full off frame restoration. So I decided to change and fill all the fluids. After adding gear oil to my Columbia rear end, I noticed a saucer sized pool on the garage floor a couple days later.mi decided to check torque on all the bolts, which were a little loose. But checking the bolt circled in the attached picture, I learned that it would almost snug up, but will not tighten all the way. Threads on the bolt look okay. So what is your advice to get this bolt tight? Thanks for all your help.
 

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I’d remove the lock washer from the bolt then see if it will tighten up. If so I’d get a new bolt a tad longer . Might also try using a stud and nut.
 
There's not a lot of meat in the housing where the bolt threads into. I would drain the oil down, clean the threads and try some sealant with a new gasket and don't over tighten the bolt. This may or may not work.
 
Hello all,

Still sorting out little issues with my newly acquired 36 Sedan Convertible and I have a new question. This car has sat for about 9 years as far as I can tell, after a full off frame restoration. So I decided to change and fill all the fluids. After adding gear oil to my Columbia rear end, I noticed a saucer sized pool on the garage floor a couple days later.mi decided to check torque on all the bolts, which were a little loose. But checking the bolt circled in the attached picture, I learned that it would almost snug up, but will not tighten all the way. Threads on the bolt look okay. So what is your advice to get this bolt tight? Thanks for all your help.
514269
 
Remove the vacuum actuator, clean and inspect the bad thread. I think the bolt is a 5/16-24 but if 5/16-18; you could tap it to 24 and assemble with blue loctite. If that's not feasible, drill and tap to take a 3/8-24 bolt.

Put a small rag or paper towel on the inside to collect shavings. Clean up and get a small magnet tool to pick up anything else left behind.

Glenn.
 
If it is leaking out of the threads on the bolt, I would clean it up good and apply thread sealant to the threads and install. Do not over tight. DO NOT rethread to a different pitch form 18 to 24. Very bad idea as you will strip the threads when you go to tighten the bolt.
 
Is there enough room in the housing for a nut? If so, you can run a bolt through the hole with the nut inside and epoxy it to the housing. make sure you don't get any epoxy on the threads and that the inside of the housing squeaky clean. If your lucky, the epoxy will hold long enough to let you re-install the bolt during re-assembly, and once it's on, it the bolt will hold the nut in place.
 
Glen has it right. A tap will fix things nicely. You also may be a little overfull. Check your Columbia instructions for lubrication. The Columbia uses 4 pints of lube and is checked at the plug that is on the Columbia housing, not the Ford housing.
 
go get some brass washers used for sealing brake line fittings and place them under NEW bolts, even thought they look good they are worn
 
I would add to what glennpm said about using a tap...dip the tap into wheel bearing grease before you start the tap in the hole - get plenty of grease on the tap. All the metal chips will be caught in the grease and not fall inside the housing. I've done this many times with excellent results. As a precaution, depending on how deep the hole was, after running the tap into the hole for several turns, I would stop and clean the grease and metal chips from the tap and dip into grease again before proceeding further.

If the hole you're working on is accessible enough, you might consider installing one of the thread repair products like a Time-Sert, or Heli Coil. When using a drill to increase the size of the hole for installing one of the thread repair devices, also use plenty of grease on the drill bit to alleviate any chips falling into the housing.
 
Can someone explain to me how running a tap through a stripped hole (thus removing even more metal from the threads) is a way to properly fix a problem such as this?
 
When you do get that threaded problem fixed, Read and adhere to the directions for filling the Columbia. Basically, you put the vehicle on 4 jack stands level, Fill via the COLUMBIA fill hole until full with gear oil. Run the car in gear for the specified minutes which fills the interior of the columbia unit with oil, shut off the car and fairly quickly, add enough in the COLUMBIA fill hole (NOT the Ford one) to again bring the level up to the hole and replace the plug.
John Connolly in AZ who rebuilds these units sells copies of the original instructions that came with a new Columbia which has the proper method. I know of at least 2 Columbias that were ruined due to not following the detailed instructions.
Good Luck
 
I know nothing about Columbia diff's, but is there enough "meat" there to install a heli-coil of the proper size? If there is ,to me , this would be the proper repair.
 
If that is a 3/8 bolt, there probably is enough room to take the vacuum can off and tap it 7/16 and drill the hole in the vacuum can 7/16. You need to be able to trap any metal shavings but you should be able to get something in there to catch them once the canister is off. Grease in the flutes of the tap can help too. When all is done, some permatex on the threads should prevent it from leaking. Good luck.
 
Can someone explain to me how running a tap through a stripped hole (thus removing even more metal from the threads) is a way to properly fix a problem such as this?

Hi Tubman,

First, the bolts are 5/16". I just checked on my Columbia. I don't know if they are coarse or fine thread. My hunch is that they are fine so for this re-tap fix my suggestion may by moot.

Fine threads have a larger tap drill size since the minor diameter is larger for fine than coarse. Fine threads have more surface area and the threads are closer to the thread major diameter which is equal to 5/16" in this case. This means that there is more meat of undamaged base material that can be tapped.

If inspection of the damaged threads is mostly on the damaged tips of the coarse threads, than there is still a significant amount of base metal that can be used for a fine thread tap. If most of the hole is wallowed out to 5/16", this re-threading to fine won't work. In many case this is not the situation.

No harm in trying the re-tap to 5/16-24. If it doesn't work out, drill and tap to 3/8. Due to the application here, there is no need to use a thread insert unless you're bothered by the larger head of a 3/8".

Fine threads have greater tensile strength than coarse thread in the same diameter.

I have used this technique a number of times up to 3/8".

Glenn

514365
 
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When you do get that threaded problem fixed, Read and adhere to the directions for filling the Columbia. Basically, you put the vehicle on 4 jack stands level, Fill via the COLUMBIA fill hole until full with gear oil. Run the car in gear for the specified minutes which fills the interior of the columbia unit with oil, shut off the car and fairly quickly, add enough in the COLUMBIA fill hole (NOT the Ford one) to again bring the level up to the hole and replace the plug.Good Luck

Too bad Columbia didn't put the fill hole high enough to avoid this nonsense!

LUBRICATION INSTRUCTIONS – IMPORTANT

With rear wheels off of floor fill rear axle through filler hole in Two-Speed Axle housing with 4½ Pints of standard Ford rear axle lubricant. (DO NOT USE CUP GREASE ) Start motor, shift transmission into high, and Two-Speed Axle control valve in high, depress clutch pedal to floor board, which completes shift in rear axle. Allow clutch pedal to return and run five minutes in this position. This is for the purpose of circulating oil through the entire Two-Speed Axle Unit. Next remove jack and with wheels on floor, BE SURE to refill axle to new oil level plug
 
Longer bolts can hit parts inside and will not fix the bad threads use the original size 5/16 x 24 x 0.56 to 0.58 long. If you want it repaired properly the housing would have to be removed and welded. I would suggest drain the fluid level, which is higher than the bad threads. Clean well and use Locktite thread repair which is very good. Do use a very small bead of RTV around both sides of a new gasket.
Follow glennpm refill instructions above.
 
so enlighten me does the bolt stop before its all the way home or does it thighten up to a piont and then just continue to spin
 
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