carb adjustment

[HxC240z]

okay I have 2 questions what is the corect level of oil in the dampers on the roundtop carbs because the haynes manual tells you to fill the dampers to the correct level with SAE 20 engine oil, BUT IT NEVER TELLS YOU WHAT THE CORRECT LEVEL IS!!! Also how do you adjust the carbs if the car isnt running (is it just guess and check??) because the Haynes manual tells you to adjust the carbs after the engine obtains normal operatring temperature but my car doesnt run and I think I need to adjust to get it to run, ( is cold enginge adjustment covered in the Z therapy video??) thanks, Ill be back monday.

[MikeW]

There are two grooves on the damper rod to indicate the high and low level. It's just like a conventional dip stick.

As for adjusting the carbs much has been written about this already, including the fact that many people decide to adjust the carbs when the problem lies elsewhere thus making things worse.

[=Enigma=]

Search here and Google. There is loads of info out there.

Your basic starting point is to screw the mixture adjustment nuts on the base of the carb all the way in and then back them out 3 full turns (1080deg). Start the car. From there you screw them each in 1/2 a turn until the car dies. This all assumes that everything else is 100%, plugs, wires, valve adjustment, etc.

Good luck. Do yourself a favor and do some more research on the net.

[Arne]

Your basic starting point is to screw the mixture adjustment nuts on the base of the carb all the way in and then back them out 3 full turns (1080deg).

NO! Everyone just passes by the REAL first step. Verify and set the float level in each float bowl! If the float level is wrong, any other "starting point" is worthless. ALWAYS set the float level first!

[=Enigma=]

Thanks for the correction Arne, and the emotion. You're right, this should always be the first step.

[wfl_colorado]

If you end up w/ too much oil, all you have to do is raise the piston to the top w/ your finger and the excess will drain off into the engine w/ no harm done.

Once you do what Arne and Enigma said and you get the car started is when you start changing the idle screws along w/ a flowmeter to get the carbs adjusted just right.

That is the basics, but there is a lot more detail on the website or on the Ztherapy video.

[beandip]

The only source of 20w oil that I have found , without buying it by the small bottle form mail order , is a Cycle shop. They have 20w Fork oil that is used for the forks on a motorcycle. I have tried several weights and for my Z far and away the 20w is the best . But do a search . There are many posts on step by step on how to adjust the SUs. Gary:)

[Dropkick]

Marvel Mystery Oil.

[zcarnut]

There are two grooves on the damper rod to indicate the high and low level. It's just like a conventional dip stick....

Note here: I have the [very] early SU's with the metal top damper rods and they do not have any of the oil level "grooves" on them. Go figure!

[HxC240z]

thanks for all the suggestions, Ill check the float levels today, I read my manual and I think I figured out how to do it. Will they not work at all if the wrong oil is put in, these are from ebay and Im not sure what oil is in them so I might open em up clean em out and refill with 20w.

[wfl_colorado]

Just use standard 3-in-1 oil from any hardware store. Use they will work, but depending on temp they may not work like they are supposed to.

[beandip]

Marvel Mystery Oil.

marvel oil is about 8w ATF is 5w both cause lean condition at first throttle opening and a stumble . 20w will allow the richer mixture to the engine just like a accelerator pump in a carburetor like on a V-8 . As to the amount of oil needed, they take about 4cc each . If over filled the excess will just be burned off by the engine , no worries . If you cannot get 20w go with some 10w30 . that will get you by nicely . Better to be thicker than thinner so the dampener can do it's job as intended . If you were running on a track and keeping the engine up in the high revs , you could eliminate the oil completely because you would be at WOT most of the time anyway . Its for normal street driving that this makes a difference . I have , over the years , heard of members trying everything from brake fluid to water looking for the '' golden bullet of power and performance ''. The makers of these carbs call for 20w for a reason. 33+ years later the debate still goes on. Gary ( Gazza ) for you bloks in Auzzy land .