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Hey guys,how much ATF do I need to put in the domes of my round top SU's? Is the dash pot also a dipstick,or am I on crack? I assume it doesn't need much oil,but I don't know much about these carbs.


Also on the Z-therapy video I got it shows tuning the carbs at 3-4k RPM's or what ever RPM you are most likely to see the most with your setup. In this portion of the video the guy use a handy service screw between the two carbs that brings the RPM's up to that level,and holds it there while he adjusts the linkage between the two carbs so they are open the same amount,and flowing the same on the Unisys gauge. That is fine and dandy on the car he is using as a test bed which is a Z-car,but my carbs don't have this service screw to hold the throttle open for me,so what do you guys suggest I use to do this short of having a friend with a really steady foot(unlikely)?

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how about use your hand doing it in the engine bay?????????????

The problem with that is I will probably be pretty shaky,and I will probably need two hands for the Unisys tool as well. I suppose I will figure out a way,but man that setup on the z-car is way easier.



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I've never gotten the proper action with ATF myself. I use 10W-30 in the winter (i'm in NC) for a little lighter action in cold temps, but use 30W in the summer (Briggs & Stratton Lawnmower oil if you have trouble finding pure 30W in the automotive stores). Ideally, I would like about 25W.


3cc, that is about 1/2 teaspoon. In other words, not much.


Read here ---




Thought you had given up and had the car for sale????

Edited by dgi
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I am using a set of SU's that are used,and I assume I need to add some fluid to them as they were shipped to me from OZ,and I bet they had to be drained out.



I had given up on the car,but now I am re-focused on it,and decided that having it running will make selling that much easier. Heck maybe after I get it running I won't want to sell it. I do like the car,but I am frustrated.

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basic sync: (engine off) have someone floor the throttle then grab the linkage for the front carb and see if it moves. If it does you will need to adjust it to where it just hits the limiter as the front carb does. close the throttle all the way then grab the front linkage and see if there is any movement before the rear. if there is movement adjust the carb mounted idle screw till they both start to open at the same time.


Fuel mix: turn the large knob in (as you look down counter clockwise) all the way till it stops then back it off two turns. fire engine and adjust idle to 750rpm. once engine is warm reach in the rear carb and gently lift the slide if the engine quits turn the front big knob out (clockwise) 2 clicks and repeat test. once the engine will stay running on 2 cyl with the rear slide lifted repeat the same on the rear carb by lifting the front slide.


This should get you running a Unisync is the best way but this will get you running.


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Use Marvel Mystery Oil, don't worry about over filling them they will seek there correct level. The thing on the end of the plunger is like a shock damper, when you pull the rod out and then push it back in you will feel a little resistance when you have enough oil in them and none when they are low on oil.


Marvel smells nice and our old engines top ends love it. My dad has used it since the dinosaurs were downtown:) He sold Austin Healys, MGs and Jags new.

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So I got the car running today. It isn't dialed in,but it is running,and idling on its own around 900-1000 rpm. I can turn it down some,but right now I am happy with it. The thing is the Unisys doesn't really raise the balls very high at idle,and the little it does is only when I have the centre part dialed way in,and chocking off the air to the point where the engine almost dies if I leave it on there long. I know the carbs need some tuning,but what about this unisys not raising the balls so far. Also what does the nut on the bottom with the fuel line from the carb affect other than the fuel level in the needle? Does this part need adjusting,and if so what am I adjusting with that,Idle speed(doubtful),high end power,low end power,other,etc??




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The nut with the spring above it is your fuel mixture adjustment, when you turn the nuts out thats richer and in is lean, adj them the same, see where you are by counting the turns in then bring them back. Run car fairly hard for a bit on a highway and shut down coast into a rest area then pull a spark plug to see if you are rich or lean go for a nice tan color. as for your uni sync it's best to set them at a high idle.


Good luck, Wharf

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