chain case drain plug

[DT]

Changed my chain case oil for the first time yesterday. Arrggg! I cannot describe how frustrating and messy it was. I give Cat props for multi-tasking components, but something that is a regular service item should NOT be this difficult, messy and time consuming.

I couldn't find where anybody did this so I decided to drill/tap and installed a 1/4 NPT at the bottom of the case. I think this will at least get most of the oil out and reduce the mess next time. I wish the case was a little thicker in that area and hope the plug won't crack the case. I used thread sealer and lightly torqued it. All is good for now-

 

[stingray719]

Changed my chain case oil for the first time yesterday. Arrggg! I cannot describe how frustrating and messy it was. I give Cat props for multi-tasking components, but something that is a regular service item should NOT be this difficult, messy and time consuming.

I couldn't find where anybody did this so I decided to drill/tap and installed a 1/4 NPT at the bottom of the case. I think this will at least get most of the oil out and reduce the mess next time. I wish the case was a little thicker in that area and hope the plug won't crack the case. I used thread sealer and lightly torqued it. All is good for now-
View attachment 114421

I thought about that too but the case being so thin worried me, let us know how it holds up please.

 

[DT]

I'm using a stainless plug for now but am trying to find a plastic replacement, possibly glass reinforced. I think this would reduce the stress in that area and be a perfect solution.

Either way, if it fails, it wouldn't be the first time I've used JB weld!

 

[MrSled]

Copper or Fiber washer might be a good idea.

 

[DT]

I initially wanted to go that route. The case is so thin I didn't think there would be enough metal for that type of plug seal and it would pull the threads out, hence the pipe thread. Unless you're talking about something else?

 

[MrSled]

I initially wanted to go that route. The case is so thin I didn't think there would be enough metal for that type of plug seal and it would pull the threads out, hence the pipe thread. Unless you're talking about something else?

I looked at it closer.. I see what you did.. but even with pipe thread, it still could drip. Keep us posted.

 

[Snowfun]

I put a 1/4" NPT stainless steel plug in my chain case. The plug is tapered and I tightened it until it was snug. There have been no leaks to date.
Correction: I used a 1/8" plug.

 

[TD Max]

1/8" NPT is a much finer thread. 1/16" finer yet so more threads engaged and easier to seal. Plus you can always go larger if you run into issues.

 

[Snowfun]

1/8" NPT is a much finer thread. 1/16" finer yet so more threads engaged and easier to seal. Plus you can always go larger if you run into issues.

Correction to my post. Thanks.

 

[DT]

I have no doubts it will seal because that's what pipe plugs are designed to do. Also, a finer thread would be even better but 1/16 & 1/4 NPT are the same -27 threads per inch so there isn't an advantage here. My only concern is it cracking my case. Apparently, I'm not the only one who has done this and am interested how it is working for others...

 

[cannondale27]

I have no doubts it will seal because that's what pipe plugs are designed to do. Also, a finer thread would be even better but 1/16 & 1/4 NPT are the same -27 threads per inch so there isn't an advantage here. My only concern is it cracking my case. Apparently, I'm not the only one who has done this and am interested how it is working for others...

You are the first I have heard of. Props to you for having the balls to do what we all have wanted to do. Keep us updated. I think you will be fine. Maybe put a blob of silicone on it to keep it from loosening. Being so thin not sure how much size changes when it gets warm. Silicone would easily be able to be removed.

 

[nherbst454]

What about building it up with JB weld then drill/tap?

 

[super1c]

What about building it up with JB weld then drill/tap?

Or better yet why could you not have a thicker flange of some sort welded on. You increase thickness and can ensure good seal.

 

[cannondale27]

Or better yet why could you not have a thicker flange of some sort welded on. You increase thickness and can ensure good seal.

That cover is Magnesium. I know it could be welded but better be good at it.

 

[Snowfun]

I asked a retired friend who was a welder about welding a piece onto the chaincase and he was very hesitant about that as the case is a casting. If it was aluminum, no problem but he did not want to put any heat to it as he was unsure as to what would happen (probably melt or distort).