Oil drain plug

Folks,

I was just at the Miata.net site looking for the torque specs for the drain
plug on my '03.
In the torque spec section it states 22-30 lbs for a 19mm plug.
I have a 17mm plug, does anyone know the torque spec for that? Or am I
being just a little anal?

Thanks

--
-----
Clark Friedrichs /

The 03 uses a 14 mm ID crush ring. The spec is the same: Use no
more than 30 ft-lbs.

If you are uring a new crush ring you will feel the crunch as it sets.
I stop at that point and I've never had it leak.


On Sat, 16 Sep 2006 20:53:22 GMT, "Clark Friedrichs"
> wrote:

>Folks,
>
>I was just at the Miata.net site looking for the torque specs for the drain
>plug on my '03.
>In the torque spec section it states 22-30 lbs for a 19mm plug.
>I have a 17mm plug, does anyone know the torque spec for that? Or am I
>being just a little anal?
>
>Thanks

I've had the '90 since it was new. Just for the hell of it, I used the
original washer over and over again. I think it finally replaced it
after about 10 years. It never leaked. I'm on the second one now.

There is no real reason not to use a new one. If none is handy, however,
the world will still turn just fine.

Ken

M. Cantera wrote:
> The 03 uses a 14 mm ID crush ring. The spec is the same: Use no
> more than 30 ft-lbs.
>
> If you are uring a new crush ring you will feel the crunch as it sets.
> I stop at that point and I've never had it leak.
>
>
> On Sat, 16 Sep 2006 20:53:22 GMT, "Clark Friedrichs"
> > wrote:
>
>> Folks,
>>
>> I was just at the Miata.net site looking for the torque specs for the drain
>> plug on my '03.
>> In the torque spec section it states 22-30 lbs for a 19mm plug.
>> I have a 17mm plug, does anyone know the torque spec for that? Or am I
>> being just a little anal?
>>
>> Thanks
>

There are a few instances of using no washer with no leaks.

"KWS" > wrote in message
. ..
> I've had the '90 since it was new. Just for the hell of it, I used the
> original washer over and over again. I think it finally replaced it after
> about 10 years. It never leaked. I'm on the second one now.
>
> There is no real reason not to use a new one. If none is handy, however,
> the world will still turn just fine.
>
> Ken
>
> M. Cantera wrote:
>> The 03 uses a 14 mm ID crush ring. The spec is the same: Use no
>> more than 30 ft-lbs. If you are uring a new crush ring you will feel the
>> crunch as it sets.
>> I stop at that point and I've never had it leak.
>>
>>
>> On Sat, 16 Sep 2006 20:53:22 GMT, "Clark Friedrichs"
>> > wrote:
>>
>>> Folks,
>>>
>>> I was just at the Miata.net site looking for the torque specs for the
>>> drain plug on my '03.
>>> In the torque spec section it states 22-30 lbs for a 19mm plug.
>>> I have a 17mm plug, does anyone know the torque spec for that? Or am I
>>> being just a little anal?
>>>
>>> Thanks
>>

I can't give you a professional answer to your question, but I believe
you should be safe be torqueing at 20 pounds. If this results in some
oil seapage, you can always go back and tighten it a little more. You
probably already know this, but traditionally car manufacturers have
made the drain plugs out of softer metal than the threads inside the
oil plug hole, in order to to safeguard against over tightening.
Theoretically the threads on the plug will strip out before the threads
in the hole, resulting in your having to replace the plug, but not
having to re-tap the hole. I would like you to first get some second
opinions on this though.

ron wrote:
> I can't give you a professional answer to your question, but I believe
> you should be safe be torqueing at 20 pounds. If this results in some
> oil seapage, you can always go back and tighten it a little more. You
> probably already know this, but traditionally car manufacturers have
> made the drain plugs out of softer metal than the threads inside the
> oil plug hole, in order to to safeguard against over tightening.
> Theoretically the threads on the plug will strip out before the threads
> in the hole, resulting in your having to replace the plug, but not
> having to re-tap the hole. I would like you to first get some second
> opinions on this though.


Ron, from what I have seen, most modern cars use an aluminum oil pan and
a steel bolt, so the threads are going to be softer than the steel bolt
unless a steel thread insert is set into the oil pan, which I have not
seen yet.

The miata oil pan does not have any such insert, you are screwing a
steel bolt into aluminum threads in much the same manner as a spark plug
into the aluminum receiving threads, which of course have been stripped
out by thousands of people.

Too much torque and that bolt will either strip the threads or crack the
oil pan. I had a quick-lube shop do that to a '90 T-Bird SC many years ago.

I have usually just taken the bolt down until tight, then a tiny bit
more with a standard short 3/8" ratchet drive. It doesn't need to be
that tight and can always be tightened further in the unlikely event
that it starts seeping.
You obviously don't want it coming loose, but over many oil changes I
have found that most people tighten both the drain bolt and the filter
far more than is necessary.

It really takes a decent amount of force to damage the pan, but those
people at Jiffy Lube can accomplish it.

Pat

Clark Friedrichs wrote:
> Folks,
>
> I was just at the Miata.net site looking for the torque specs for the drain
> plug on my '03.
> In the torque spec section it states 22-30 lbs for a 19mm plug.
> I have a 17mm plug, does anyone know the torque spec for that? Or am I
> being just a little anal?

As I can't get a socket onto mine, I do it as tight as I can with a ring
wrench. Given that I will generally be lying on the ground and doing
this at arm's length, I doubt I put more than 20 ft-lb on it. No
problems in about 5 changes.

To those of you who enlightened me on the oil pan threads being
alumnium, I thank you. I though they were still made the old way. I
guess my age is showing. Ron

On 18 Sep 2006 04:16:26 -0700, "ron" > wrote:

>
>To those of you who enlightened me on the oil pan threads being
>alumnium, I thank you. I though they were still made the old way. I
>guess my age is showing. Ron


Try one of these and you'll never worry about it -
http://www.fumotovalve.com/

> It really takes a decent amount of force to damage the pan, but those
> people at Jiffy Lube can accomplish it.

On my '96 the guy opened the oil container with a flourish that sent a
tongue of oil across my engine, fenders, and even the underside of the hood.
So he restrained himself as he poured the subsequent quarts in... all
without his pal having replaced the drain plug.

Second time around (after they put the plug in) he didn't splash any more
oil around, but broke off my dipstick doing the final check.

If you go to these places, WATCH THEM!

miker