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Stromberg adjustment screw tight 175CD

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Richard_Brown

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Fresh rebuilt carbs, put them on last year but never drove the car, while trying to trouble shoot why it was running badly, I suspected something with the rear carb, I took the adjuster screw all the way out, after putting it back its super tight, like really tight and I can not turn it all the way to the top so its running too rich.
I made sure it was not cross threaded or anything and the threads looked fine. not sure if a O ring or something may be in the way.
Granted all this, the float must have been stuck from sitting a year, I tapped it on the side with a screw driver handle and it smoothed right out in an instant.

Now wondering why the screw is so tight, it was not like that beofre I took it out, did I do a NO NO by taking it all the way out?
 
Did you rebuild the carbs yourself? If not, call your rebuilder.

I took mine out last year to replace the o-rings. My adjustment screw went back in fine after replacing it so you might need to pull the carbs to see what is gumming up the works. Take a look at your factory manual because there is a sequence of getting everything lined up.

I am not sure if that helps, but someone more eloquent will chime in with specific details.

Good luck.
 
Turning the adjuster clockwise raises the needle. Once the needle is fully up, you only have 2-1/4 counterclockwise turns to play with to lower the needle.
Are you trying to turn the adjuster clockwise because once the needle is up all the way, the adjuster won't turn in that direction any more.
 
He has a TR4, which I'm thinking has an adjustable jet, instead of the adjustable needle found on the later ZS carbs ...
 
poolboy said:
Turning the adjuster clockwise raises the needle. Once the needle is fully up, you only have 2-1/4 counterclockwise turns to play with to lower the needle.
Are you trying to turn the adjuster clockwise because once the needle is up all the way, the adjuster won't turn in that direction any more.
Click to expand...


no its far from all the way up, but good thought there
 
TR3driver said:
He has a TR4, which I'm thinking has an adjustable jet, instead of the adjustable needle found on the later ZS carbs ...
Click to expand...

No I have a 4A not a 4, but it is #35 built of 4A's.
interesting though that you say this because I think in my parts there is a kit for adjusting, but how can I tell if it is adjustable jet vs needle?
 
The jet adjustment sticks out of the bottom of the float bowl, item 13 below. On the later 'emissions' carbs, the needle adjustment is hidden inside the damper and takes a special tool to turn.
 

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TR3driver said:
The jet adjustment sticks out of the bottom of the float bowl, item 13 below. On the later 'emissions' carbs, the needle adjustment is hidden inside the damper and takes a special tool to turn.
Click to expand...

I have these, not the later emissions carbs,
I assume you should never unscrew the adjustment screw all the way out?
 
Not sure if this has anything to do with your problem but if you took the jet all the way out you will need to go through the procedure to re-center the needle.
 
Once they are rebuilt the kit instructions are to screw the jet in all the way and back off 1 1/2 turns for a starting point. That got me very close. The needle has a thicker portion inside the piston which is set flush with the piston bottom. Make sure the pistons drop correctly at that point.
 
I would suggest just taking that carb off, turning it upside down on a workbench and taking stuff off until you find the problem. You may have bent the needle, which would not be a good thing. It's not that hard to take the bowl off. The adjustment screw goes up from the bottom and an O ring keeps the bowl from leaking around it. The jet has a little shoulder on it that should keep it from falling out when you took the screw out. The jet is inside an aluminum piece that you can also remove. It sounds like something got into a bind.
Before going through that though, you might just take the screw back off, use a mirror to look at the jet and maybe wiggle stuff around with the screw out. Raise and lower the piston, work the throttle, etc., and see if you can screw it back in there and get it to do what it is supposed to.

If all that fails, you could do like I did and modify a GM EFI manifold to replace those carbs and use a Megasquirt controller. ; ))

Dan B
 
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