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ZS Carbs

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TR4

TR4

Jedi Knight
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I have heard ATF Type F is a suitable replacement for the ZS carbs. The FLAPS nearby has Type FA, would that be the same thing? They did not know if it would work in the carbs.
 
There is no end to what people use in the carb dampeners -- ATF, motor oil, Marvel Mystery Oil. The difference, of course, is the weight of the oil and what works best may depend in part on temperature, condition of the engine, what you expect, etc.

I suspect that there is little perceptible difference between ATF F & FA for what you are using it for.
 
I use 3 in 1 oil in mine that is 20 W.

Cheers,
M. Pied Lourd
 
I got a lift and it needed 3 gallons of a hydraulic oil that was only sold in 5 gallon cans. I'm using that extra 2 gallons on everything but pancakes. Seems to be about right for the carbs.
 
Geo Hahn said:
There is no end to what people use in the carb dampeners -- ATF, motor oil, Marvel Mystery Oil. The difference, of course, is the weight of the oil and what works best may depend in part on temperature, condition of the engine, what you expect, etc.

I suspect that there is little perceptible difference between ATF F & FA for what you are using it for.
Click to expand...
:iagree:

FWIW I just learned a whole lot of things about 3-in-one oil that I didn't know before. Most importantly, it is no longer one product; the name was bought by the WD40 folks in 1995 and they now have quite a few different products called "3-IN-ONE" something or other:

fullfaml21673895.jpg

https://www.3inone.com/products/

Also FWIW, although the difference was relatively subtle, there were distinct differences between various "weights" of oil in the carbs and how my 59 TR3A (with SU H6 carbs) responded to the throttle. Contrary to what you might think, heavier oil actually produced a sharper throttle response, while thinner oil made the engine seem sluggish. I found that 20 weight motor oil produced about the best response for me. Thicker oil actually made it somewhat difficult to apply throttle smoothly.

The differences were less pronounced on the Stag (with ZS carbs), but 20 weight still seemed to be about the best. ATF produced a slight "lean bog", while 40 weight didn't seem any better or worse than 20 weight but would probably waste some fuel.
 
TR3driver said:
Also FWIW, although the difference was relatively subtle, there were distinct differences between various "weights" of oil in the carbs and how my 59 TR3A (with SU H6 carbs) responded to the throttle. Contrary to what you might think, heavier oil actually produced a sharper throttle response, while thinner oil made the engine seem sluggish. I found that 20 weight motor oil produced about the best response for me. Thicker oil actually made it somewhat difficult to apply throttle smoothly.
Click to expand...

This makes sense, the oil reduces the rate that the piston rises, increasing the airspeed in the carb, and INCREASING the amount of fuel sucked in causing the mixture to become richer. The thicker oil results in a richer mixture for a slightly longer time. Thin oil lets the mixture thin out resulting in a slight loss of power.
 
Well, after looking at all the options, I am leaning toward using 3 in 1 oil since it comes in that nice dispenser that would be convenient to use and not spill on the Carbs.

Thanks for all the advice..........
 
Try the 3-in-1 20 wt (blue bottle). Regular 3-in-1 (red) is closer to a 10 wt.
 
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