TOPIC:

Kawasaki Part No. 57001-208 ... Fuel Level Gauge ... Does anyone know where this tool (or equivalent aftermarket) can be had? It is screwed into the drain plug of a float bowl to check the fuel level within that bowl. It works like a carpenter's liquid level.

If the part is obsolete and can not be obtained ... What are the thread specs on the drain plug? I'll make one myself. (1979 KZ650-D2 with Stock Mikuni VM24SS Carbs)

Post edited by: BeeGee, at: 2005/11/06 12:06

BeeGee wrote:

Kawasaki Part No. 57001-208 ... Fuel Level Gauge ... Does anyone know where this tool (or equivalent aftermarket) can be had? It is screwed into the drain plug of a float bowl to check the fuel level within that bowl. It works like a carpenter's liquid level.

If the part is obsolete and can not be obtained ... What are the thread specs on the drain plug? I'll make one myself. (1979 KZ650-D2)

Here's a clever one that "Ibsen" put together:
kz400.com/RepairpicturesFrameset.html
(scroll down about 1/3 of the way)

This is basically what I hear most people do with small variations.

I was able to do it without a fitting at all. I have some rubber hose that just happens to be almost the exact size perfect for threading right into the hole...

Post edited by: biquetoast, at: 2005/11/06 11:50

Thread size? Anyone have the 'thread size' of the drain plugs to the float bowls of Mikuni VM24SS carbs?

The drain bolts are 6mm, pitch is .75 mm.

OnkelB wrote:

The drain bolts are 6mm, pitch is .75 mm.

Does that mean .75 threads per mm or .75mm per thread?
Just curious.

OnkelB wrote:

The drain bolts are 6mm, pitch is .75 mm.

Does that mean .75 threads per mm or .75mm per thread?
Just curious.

Almost too simple to explain. Just follow Biquetoast's advice and use a clear plastic tube "threaded" into the float bowl drain screw hole. Forget about the thread size and all that. Just visit your local builder supply or hardware store and pick up a few one foot lengths of different size clear plastic tubing (outside diameter)so one of them will fit "thread" into the drain screw hole. If afraid to just eyeball it, then take a drain screw along with you to help with the sizing decisions. This isn't rocket science, and there's no way to harm the threads inside the float bowl with the plastic tubing.

Thread the tubing into the drain hole of an empty float bowl, hold it dead steady against the outside of float bowl, turn on the petcock and watch as the fuel simultaneously fills the float bowl and the plastic tube, and make note of the fuel level when it stops rising. The fuel level inside the float bowl and inside the plastic tube are identical (this is the Law of Gravity per Isaac N., or Boyles Law, or somebody).

If the tubing was allowed to move during this exercise, you screwed up -- no biggie -- just drain the float bowl and re-test.

JimatMilkyWay wrote:

OnkelB wrote:

The drain bolts are 6mm, pitch is .75 mm.

Does that mean .75 threads per mm or .75mm per thread?
Just curious.

Patton wrote:

Almost too simple to explain. Just follow Biquetoast's advice and use a clear plastic tube "threaded" into the float bowl drain screw hole. Forget about the thread size and all that. Just visit your local builder supply or hardware store and pick up a few one foot lengths of different size clear plastic tubing (outside diameter)so one of them will fit "thread" into the drain screw hole. If afraid to just eyeball it, then take a drain screw along with you to help with the sizing decisions. This isn't rocket science, and there's no way to harm the threads inside the float bowl with the plastic tubing.

Thanks for the reply Patton. I am afraid that I failed to make myself clear. I have no problem either with sizing or threading the silicone tubing into the bowl drain port. I just like to know all kinds of useless stuff and I have simply never pondered the "unit of measure" for metric thread pitch. The reason I ask, is because it seems backward in one respect.
US std 1/4 - 20 bolts have twenty threads per inch. 1/4 - 32, for example has more threads per inch and is therefore fine thread.
Well, as I was studying the metric nuts 'n bolts at my local Ace Hardware, I saw that .75mm pitch is finer than 1.5mm pitch. Well if you "read" it as .75 threads per mm, then 1.5 threads per mm would be tighter together and therefore finer thread. And that ain't the case.
No reply necessary. I will ponder it a while longer. Maybe I have just had one, or two, or more too many Mountain Dews.

Post edited by: JimatMilkyWay, at: 2007/01/24 00:30

.75mm pitch is finer than 1.5mm pitch.

And here is why:
THE METRIC THREAD DESIGNATION USES PITCH IN PLACE OF THE MORE FAMILIAR U.S.A. METHOD OF THREADS PER INCH. PITCH IS THE DISTANCE IN mm FROM ANY ONE POINT ON A THREAD TO A CORRESPONDING POINT ON THE NEXT THREAD, WHEN MEASURED PARALLEL TO ITS AXIS.
METRIC COARSE THREAD DOES NOT HAVE TO HAVE PITCH SPECIFIED. THE ABSENCE OF THE PITCH SPECIFICATION INDICATES THAT THE THREAD WILL BE FROM THE COARSE THREAD SERIES.

Source quoted: Thread Identification

Does that clarify it? And now I know too!

Post edited by: pumps, at: 2007/01/24 00:58

Yup
Oh, it clears it up alright, except that, if you think about it, you have to read the metrics as "mm per thread" or, Mathematically, since: T=threads mm=millimeters & in=inches then for US std we have T/in and with metrics it must be read mm/T. And like who the hell cares!
Good Night!!

At risk of stating the obvious, a few wraps of tape dope around the end of the clear plastic tube may tighten the fit when "threading" it into the drain hole and thereby reduce or prevent any leaking while testing. But this should not be necessary.

Actually, a little leakage around the "thread" is immaterial to the measurement (if less than the volume of fuel running into the float bowl inside the carb).

Patton wrote:

At risk of stating the obvious, a few wraps of tape dope around the end of the clear plastic tube may tighten the fit....

I got 'er sealed off with _no_ leaks last night. Anyone who is interested, try this. I took a scrap, 20cm, or so piece of clear tubing that was 8mm OD, then put a fast taper on it using a dremmel with a 20mm or so (not critical) grind stone. Then, with only a half twist to thread it into drain port, it didn't leak, plus it held/holds itself stationary.
I only had time to check the carb that I was sure leaked, but sure enough, the fuel level is exactly even with very top of float bowl, instead of 3 or 4mm below it.
The last thing I did before my beauty sleep was to run the overflow tubes from each carb into a separate cup to catch overflow fuel. Now, when I get home I will be able to check each one to see which has a problem.
If you do this procedure, be sure to put bike on center stand then chock/shim front wheel so bowl top is level.