I've got 10W-30 in mine, but only because I haven't made it out to the motorcycle shop to get 20 wt. I can confirm that ATF doesn't work all that well, as I tried that before changing to the 10W-30.

I know I've posted this before and someone else mentioned it above:

http://www.wd40.com/Brands/3in1_product_info.html

You'll notice that the blue and white can is SAE 20, only costs a couple of dollars at any hardware store, and is the perfect size and has the perfect nozzle for squirting in a few cc's.

Ah, the cause of the stumble finally revelled....

Must replace the ATF with 20W and see the difference!

MOM

Just wondering...

If 10W-30 will work, would something like 5W-30 or 5W-20 be better? I notice that a most new cars in the U.S. require one of those oil weights anymore, so both are widely available.

I know I've posted this before and someone else mentioned it above:

http://www.wd40.com/Brands/3in1_product_info.html

You'll notice that the blue and white can is SAE 20, only costs a couple of dollars at any hardware store, and is the perfect size and has the perfect nozzle for squirting in a few cc's.

Hey! Thanks for the tip Mike.

Just wondering...

If 10W-30 will work, would something like 5W-30 or 5W-20 be better? I notice that a most new cars in the U.S. require one of those oil weights anymore, so both are widely available.

By the way Mike thanks for the blue can of 3 in one . I have never see that stuff in any store. I have a qt of fork oil and that will last me the rest of my life . but I would use it if I didn't . To answer the question of 5w-30 or 20 . I wouldn't put it in my engine. And remember these engines are a design that dates back to the '50s When Mercedes was building it as there 4 banger. True today's new iron use lighter oils but my engine is a 30 year old design , I run 10w30 . and no lighter. The dampener is dependent on the weight or thickness of the oil to slow down the rise of the vacuum piston. With light fluid being lighter than 20w oil the piston snaps up and allows too much air to flow as soon as the butterfly is opened. There is not a proper amount of fuel in this air and thus a lean condition. This is for only a split second but it causes the stumble like a ignition that is weak. Then the engine takes off when it recovers and as long as the RPMs are up there is no problem . But when at idle and the throttle is opened this is where the dampener must do it's function. This is the best I can do to explain this , I hope it makes since to others . If not , take my word for it. Gaza AKA Gary

hey I opened up the float and adjusted it like suggested and it needed it too, but I had a bigger problem just for kicks I decided to check the jet that the float controlls and it was completly plugged with this stupid rubber sealing wrap that was on the threads of the fitting that came with the carbs. I cleaned it out and now it should work. The gasket that was on the float cover to the float chamber was dissintegrated and advanced dosent carry em, does any one know what theyre made of so I can make my own??

The float cover gasket is not important. If the needle valve gets stuck the bowl will fill up and the fuel will leak out. With a gasket in place it will go through the hose to the air cleaner where it will puddle up and leak out.

Just changed from MMO to "3 in 1". :eek:

No longer is there fluttering in the carbs on acceleration! :sick:

Much better throttle response!! My accelerator pedal actually gives positive feedback for the first time!

YMMV, but it did wonders for this 73 with round tops!

Kudos to Gary (beandip) for the best explanation for using a specific weight of oil that I've ever seen.

20 wt. carb oil might be even better, but I think "3 in 1" gets it pretty close and is available just about everywhere.

Again thanks for this thread!

Another small but significant mystery solved for me. :stupid:

Jim D.

"Zup"

Just for reference, here is some great info on the subject of damper oil.

http://www.jetlink.net/~okayfine/su/damper.html

I didnt realize ATF was such light oil. My carbs had it in them when I bought the car and I have always used ATF, but I have never had any signs of hesitation or stumbling. However I will switch over th 20W eventually.

Got it running but I still have some fine tuning to do, does anyone know where to find a uni-sun or any other flowmeter because I called advanced auto parts, napa, and atuo zone advanced had something for 50$ but I though that was too much, I also tried summit but they put me on hold forever ( I hate summit with a passion!) If it helps I live in kent,OH. Also in my driveway I noticed that the clutch grinds when its put in reverse only when at an angle(on a hill) any one know what would cause that???