Has anyone else ever stripped their oil pan threads?

[bwringer]

On my bike, the oil drain plug is a 19mm hex. The drain plug on the final drive unit is 21mm. So there.

13/16*25.4=20.6375mm (25.4 mm/inch)

In other words, close enough to use either. Sometimes. Maybe.

In the US, spark plug sockets are usually labeled in inch sizes (why anyone thinks this is less confusing, I'll never know), but the spark plug and drain plug hex (and every fastener on your bike, and every fastener on just about any American car made after 1975) are actually metric.

I remove the 21mm lug nuts on my Toyota (made in the USA) with a lug wrench marked 13/16.

Lawnmowers, Hardley-Ablesons, and other examples of farm machinery are the last refuges of inch size hardware in the US. I wish they would abolish the inch system forever, and require all hardware stores to carry plenty of metric allen-head bolts in stainless steel... sorry, drifted off topic there.

Sure, you can usually get away with using a 9/16 wrench on a 14mm fastener, or 5/16 instead of 8mm, or even 1/2 on a 12mm (sloppy) or 13mm (tight), or 3/4 on a 19mm, or 13/16 on 21 or 22mm, etc. We've all done it.

But isn't it nice to actually use the correct tool for the job?

In any case, all this is further complicated by the fact that many of us are probably already running around with replacement oversize drain plugs put there by a klutzy previous owner. (I was, and I didn't really notice for a few years.) Many of these were probably just mashed in there with inch size threads instead of the correct 14 X 1.25 mm thread.

 

[jonr]

I have been down this alley recently. Stripped the oil plug years ago and until recently, I have just snugged it in with no problems. Well, I just took a 1000 mile trip to the Galena rally and the sucker repeatedly tried to unseat itself. I had oil leaking to the point I thought I would have to turn back.

Well, I tried to find an oversized plug and my GS750 is a 14mm x 1.25 pitch plug. The auto parts stores seemed to only have 14mm x 1.5 pitch. Next step: rethread. Well, just about that time I came across another oil pan on ebay. Stupid thing is that I did not install it before my road trip. I really didn't look it over, and all the bolts on mine are really accessible.

My vote is for a different pan OR pull the old and install a piggy-back plug. The real kicker here is that my factory service manual states that it only gets 7 ft-lbs of torque! No wonder it's so easy to strip.

-J

 

[Anonymous]

I used the 21mm socket last night to remove my drain plug, and it fits perfectly. Both my 13/16 short socket and my 13/16 spark plug socket were too small. I got the plug out and back in with no thread problems.

Now the bike sneezes oil out around the filter cover, but that's a different issue. I took a chance on re-using the O-ring, but that gamble didn't pay off. Time to get a new one and maybe a tube of RTV.

Thanks for your help folks.

Dave

 

[mcycle-nut]

I didn't think that there was a size difference between models, but maybe :?:

Yes, there is. I don't recall the sizes, but my 750 and '82 1100 require different size sockets.

 

[bwringer]

Jon, you might want to heli-coil that new pan before sticking it on your bike. You just KNOW those soft aluminum threads can't wait to fall apart on you!

It's the same thread as the spark plugs, so it ought to be easy to find a heli-coil. And it sure would be a lot easier to put the coil in with the pan sitting on a workbench.

I've also noticed a vast difference in quality between drain plugs from different stores. I went through this battle on a car a while back, and certain discount auto stores stock drain plugs that look like the threads were sand-cast. Very rough, very poor quality. NAPA or CarQuest usually have good stuff.

 

[jbutt_mcse]

Stripped threads on Oil pan PLUS a whole lot more

Stripped threads on Oil pan PLUS a whole lot more

Hi all,

First of all let me say I love myGS. I'm new to riding, just got my license this summer after my brother "lent" me his rebuilt 1981 GS400L I use it for around town and some short trips. Its been dropped at least once, (not by me or my brother) and so there are lots of "non standard" parts

My first post after looking around here and seeing what people are doing to fix stripped threads in the oil pan.

I have been using a rubber compression nut to keep the oil in my 1981 GS 400L however this has been over tightened a couple of times and now has tears in the rubber so there is almost a very slow but constant drip (Thank god for kitty litter)

It would appear that not only are the threads stripped but it would appear that the oil pan hole ahas already been drilled out and increased in size. Looks like it could be 15mm in size already.

My question, Should I try to rethread the pan as it is? Should I remove the pan and get it drilled larger and fitted with a oil plug? If so where would I get a replacement gasket ? And of course where would I get a replacement oil pan?

All help appreciated. Many thanks

Sincerely,
Jonathan Butt
Cranbrook BC Canada

 

[mdole]

The oil drain plug has had a really spongy feel to it ever since I got my GS750. While I have it torn down I got another oil pan from the junkyard that has a really nice drain plug (my old one looked like some one had used vice grips on it) and is in decent shape for $20.00.