Thread size for Oil Drain bolt - XJ550?

after 26 years and 50+ oil changes, the drain bolt (female) threads in the oil pan are finally worn to the point the bolt can't be properly torqued. The bolt is fine however. I want to order a tap online, but unsure of size. Manual is obscure - is it the one listed as a "strainer bolt" and therefore a M14 x 1.5 thread pitch?

TIA

 

that sounds right but i'll measure it later to be sure
but
if the bolt is 14x1.5 a tap that size won't help, you'll have to go bigger, maybe to 16 then a tap would cost more than a used oil pan.
tap might be around 40$

 

oops thats a 550, i don't have one to measure

 

As a "use once" item I can make do with a cheap tap - Ebay has them for under $10 with free shipping. I'm not looking to oversize the hole and bolt, just to "clean" the rounded aluminum threads and reshape them back to where the bolt bottoms firmly without spinning past them under the appropriate torque.

you are correct though, a quality tap around that size was $35 bucks at the place I bought my spark plug hole tap.

 

If the threads are so worn that you can't get the bolt tight, I don't think "chasing" the existing threads is going to help.

You could do a HeliCoil; go to a slightly oversize drain plug; pull the pan and have the threads welded up and then re-tapped; or just eBay another less-used oil pan.

 

I'll be pulling the pan to do this anyway, and the threads are very visible so I'll be able to have a good look at their condition regardless. If chasing the threads doesn't work (I'll be able to bench test for torque before re-installing the pan), then I'll likely go the weld and re-tap route. If that fails, well - red locktite has gotten me through 2 seasons already (lol) OR its a 2 hour return ride to the "local" boneyard some weekend and another $50 or so.....

In either case, I'll think I will risk the $10 before having to source a new pan. So, is it true that the thread size is indeed M14 X 1.5 pitch?

 

Probably. Throw a thread gauge on the drain plug to confirm.

The drain plug is common to all of the XJs and most XS's of the era, 550, 650, 750, etc., so somebody (like Mr. P.) with other than a 550 should be able to confirm for you. (I'm at work.)

 

This is correct.

 

1. You need a thread repair tool to have any chance of saving the threads that are left. A chase is for cleaning crud out of good threads, and a tap is for cutting new threads. Neither of those tools will do the job that you need to do. A tap will remove material and make the threads worse than they are now. A thread repair tool is designed specifically to push the remaining material back into the shape of the original threads.

2. If the threads cannot be salvaged there are better, and easier methods for repair than welding and retapping the hole. Any halfway decent auto parts store will carry oil drain repair plugs, which will give you a brand new steel drain plug, and steel threaded drain, for less than $6.00. It is a permanant, leak free, repair that requires no special tools beyond a handheld drill. There are also oversized, self tapping repair plugs available.

The only reason that you might want to weld, drill, and retap would to keep the original look if you had a show bike, or had something with more value on the collector market.

 

http://www.xjbikes.com/Forums/viewtopic ... drain.html

 

I was going to say put a heli-coil in it, but you beat me to it. the best way to go in my opinion. they are stronger than the original threads.

CN

 

Or, you're Canadian. JUST KIDDING!

I do have to agree. The "oil drain repair" option is easily do-able and a lot cheaper and easier to do; as is a Heli-coil.

Personally, faced with the same circumstances I, (being the originality Nazi that I can be at times) would simply troll eBay and pick up another oil pan for pennies on the dollar. Being that you're pulling it anyway. Easiest solution is to bolt up a "new" one (don't forget a new o-ring for the oil level sending unit) and be done with it.

 

mmmm given the "sight unseen" factor, you just may just end up with another "original" worn thread again though

 

4nik,

IMHO Heli-coil and forget about it.

Roc