Ever broken something like this?

[ScottOkla]

This is one of the drains for the hydraulic fluid on my father's B7610. It was leaking fluid a bit from here and when he tried to tighten it, this broke off.

We are debating how to fix this to make it not leak, but still be able to remove it to drain the fluid out in the future. I am going to find a longer threaded plug in order to see if it will screw in and hold on the last couple of threads before I remove the chunk that broke off the old short one.

Any suggestions from you more experienced guys?

(My first attempt to attach images, so please excuse me if it doesn't work correctly.)

 

[hd61960]

JB weld is supposed to work well on things like that

 

[AlanB]

Man, that is a tough looking one.

First thought would be to grind down to the break area and flush face it, then make a special bolt / plug maybe with an allen head.

Second thought, depending on what it is, is to disassemble the unit, weld solid and remachine threads etc. on it. Sometimes better just to get a new casting, but sometimes it works out to repair.

 

[3RRL]

It looks like it's a face seal against that washer, and I think your threads are straight ... no taper. So just putting a straight threaded plug of similar thread would not necessarily seal it.
You could run an NPT tap in there a bit deeper and use a short pipe nipple or pipe plug. That would be the easiest IMHO. If you wanted to use a short nipple, you could put a small open/close valve on the other end.

 

[Farmerford]

1. If needed, tap the existing threads so they extend 3/8 to 1/2" past the break into the hole with a bottom tap
2. Pour a quart or two of (cheap) transmission fluid through the fill pipe to flush out any chips
3. Get a new bolt 1/2" or so longer than the old one
4. Drill bolt head for a safety wire
4. Clean the threads with brake cleaner, carburetor cleaner, lacquer thinner on a Q-tip
5. Install bolt with plenty of "blue" Loc Tite
6. Install safety wire and tie it off so it pulls the bolt into the hole;
7. Give Loc-tite plenty of time to set.
8. Try it out.

That method works pretty good on through holes into water jackets, etc.

 

[DGS]

1. If needed, tap the existing threads so they extend 3/8 to 1/2" past the break into the hole with a bottom tap
2. Pour a quart or two of (cheap) transmission fluid through the fill pipe to flush out any chips
3. Get a new bolt 1/2" or so longer than the old one
4. Drill bolt head for a safety wire
4. Clean the threads with brake cleaner, carburetor cleaner, lacquer thinner on a Q-tip
5. Install bolt with plenty of "blue" Loc Tite
6. Install safety wire and tie it off so it pulls the bolt into the hole;
7. Give Loc-tite plenty of time to set.
8. Try it out.

That method works pretty good on through holes into water jackets, etc.

Ok,but how are you going to use it as a drain plug after the repair you have just described
DGS

 

[kthompson]

Ok,but how are you going to use it as a drain plug after the repair you have just described
DGS

How about skipping the Loc-tite and using Teflon tape?

 

[firemanpat2910]

plug hole with a rag to keep debri out. cut and grind broken part smooth and flat, just a shorter version of orriginal. retap hole for new bolt, use rubber washer under bolt, dont over tighten!!!. how big is the whole removeable piece? its hard to tell by pictures. You might be better to remove and have a machine shop grind and retap.

 

[Farmerford]

Blue Loc Tite will loosen with a wrench. It is Red Loc Tite that must be heated to about 400 deg F to release.

I know it works well with anti-freeze. For example, on my old 1977 Bronco two of the long 5/16 bolts holding the water pump to the block go through the outer block wall into the water jacket. The shop manual calls for Blue Loc Tite on those threads. It blocks 200+ deg coolant under 14 psi, and I suspect it will work on 200 deg (at most) oil under maybe 1/2 psi.

And it is almost the easiest of all the fixes to try. If it doesn't work you can take a more drastic approach.

A little drip won't hurt anything, and will keep the underside from rusting.

 

[Egon]

Ouch!

Have you talked to the Dealer?

 

[ScottOkla]

I am trying to digest these replies. Neither of us are very experienced or skilled in the mechanics department. My experience comes from fixing things he breaks, which keeps me busy.

Our first thought (after the service department at the dealership gave him a quote to replace the entire piece) was to get a slightly longer bolt that would reach the remaining threads, and then use JB Weld to keep it all together. We realized that we would not be able to drain the fluid from this location again, but there are 3 other drains that would get most of the old stuff out in the future. We are at the 300hr service now.

Still thinking and digesting.

Thanks.

 

[davkir]

I agree that re-tapping the hole is the way to go. If you have never done this sort of thing, you probably should find some experienced help. It looks like it's a hard place to access also.
(Note: If you coat the threads on the tap with thick grease, wheel bearing grease works well, most of the metal shavings will stick to the tap and can be remove from the hole.)

 

[sixdogs]

I would talk with the dealer again. Surely he has seen this before and has more ideas than we might .

Plan B might be to use JB Weld to stick the part on and then ask the parts guy if there might be room ro tap deeper. I have seen worse and have seen JB Weld hold in places it should not have. In fact, i glued a lip of concrete back on to the edge of my barn pad and drive a 7500 lb tractor over it--and right on that edge--and it's been three years.
There is also an expandable LocTite that fiils small spaces and this might help with the threads if not too hard to break loose later. I used it to fill a space around a bearing race that was spinning and it worked great.

 

[SimS]

Scott;

Have you thought of a hollow stud or threaded rod? You could tap the hole deeper and JB Weld/Loctite the hollow stud/rod into the hole and then put a acorn nut or cap on the other end of the stud/rod(with teflon tape). The removable nut/cap would allow draining in the future. Take a look at McMaster's web site or other industrial supply houses, they should have some thing to foot the bill. I can't tell the size of the drain bolt but you might even be able to tap the hole and install a brass fitting or short nipple if the thread depth could be reworked. Good Luck.

SimS

 

[Skyco]

Now that is a dang good idea!

 

[Gary Fowler]

I dont think I have ever seen a flat thread plug break out a chunk like that. With tapered threads and a lot of overtightening, that kind of thing could easily happen. I think you must have had a defect in the casting to start with. You stated it was leaking so you tried to tighten it. Likely it was cracked casting to start with. The Tractor looks fairly new. Check your dealer for warranty on this before attempting any repairs. If not warrantied, then I think the advice given to flatten the surface directly behind the break, either by machining or really carefully grinding it so it has a really flat sealing surface, Tap the threads deeper and use either a plug with an O-ring seal or a rubber washer seal. DO NOT OVERTIGHTEN.

 

[3RRL]

Scott;

Have you thought of a hollow stud or threaded rod? You could tap the hole deeper and JB Weld/Loctite the hollow stud/rod into the hole and then put a acorn nut or cap on the other end of the stud/rod(with teflon tape). The removable nut/cap would allow draining in the future. Take a look at McMaster's web site or other industrial supply houses, they should have some thing to foot the bill. I can't tell the size of the drain bolt but you might even be able to tap the hole and install a brass fitting or short nipple if the thread depth could be reworked. Good Luck.

SimS

There you go, "basically" what I suggested in post #4.

 

[ScottOkla]

This has been a big help.

To answer a few questions and give more info:

I was not there to see the original leak or exactly what he (Dad) did exactly to break it off. I did the 50hr service for him and I don't think I over-tightened, although it's possible. I cannot even say for sure the leak was coming from this drain plug. I recall at the 50hr service that there were 4 drain plugs in all, but if this one were not accessible in the future we would not be able to get .5 to 1.0 gallons of the total 3+ gallons out. The 300hr service is due now. It is 2.5 years old.

The dealer expected the labor alone to remove and replace the entire part to run about $600. Another service person suggested to my dad the JB Weld and just not using that plug again. I have not personally talked to any of these service people yet.

The tractor gets much use mowing in rough areas with lots of seedlings and downed branches. A branch could have caught it just right and impacted it, although I would not have ever thought this possible until I have seen some of the ways sticks and branches have hit things lately (our ice storm last winter dropped stuff everywhere). The 7610 is great and keeping the trails clean, but we've stopped some of the harder use lately.

The suggestions by 3RRL/SimS/Farmer seem like excellent ideas if I can get the threads tapped deeper. Looks like I will be learning some new things regardless.

Scott

 

[DGS]

This has been a big help.

To answer a few questions and give more info:

I was not there to see the original leak or exactly what he (Dad) did exactly to break it off. I did the 50hr service for him and I don't think I over-tightened, although it's possible. I cannot even say for sure the leak was coming from this drain plug. I recall at the 50hr service that there were 4 drain plugs in all, but if this one were not accessible in the future we would not be able to get .5 to 1.0 gallons of the total 3+ gallons out. The 300hr service is due now. It is 2.5 years old.

The dealer expected the labor alone to remove and replace the entire part to run about $600. Another service person suggested to my dad the JB Weld and just not using that plug again. I have not personally talked to any of these service people yet.

The tractor gets much use mowing in rough areas with lots of seedlings and downed branches. A branch could have caught it just right and impacted it, although I would not have ever thought this possible until I have seen some of the ways sticks and branches have hit things lately (our ice storm last winter dropped stuff everywhere). The 7610 is great and keeping the trails clean, but we've stopped some of the harder use lately.

The suggestions by 3RRL/SimS/Farmer seem like excellent ideas if I can get the threads tapped deeper. Looks like I will be learning some new things regardless.

Scott

AT 2.5 years old isn't 7610 still under warranty.
Or maybe Kubota could meet you halfway as it looks like a casting defect in the picture.
Good luck
DGS

 

[john_bud]

I also would clean it out, degrease it brake cleaner and JB weld in a hollow bolt with an allen head nut downt the center for drain function. It will drain Sloooooooow, but slow is better than no.

jb