TR6 TR6 Zenith Carb Problem

[RomanH]

HI everyone!
I have had some carburetor problems with my early 1974 TR6 since I bought it. I have never been able to achieve a proper mixture and have always been runing very rich. I thought that slowly I was getting on top of everything after adusting the float level, changing the throttle shaft seals and generaly making sure every gasket was sealing properly.
Tonight I was replacing the seals on the needle adjusting screws when I noticed something I thought was odd. After I removed the air pistons from the carb bodies I saw that they were wet with gas and a small amount spilled from the pistons. This seemed strange since I didn't run the car for four days. I also saw that the carburetor walls and throttle plates were also wet with gas.
I wiped everything dry and sat and looked at the area around the jet. After about a minute I noticed that the gas was again wetting the carb walls! I wiped everything down again and this time saw that the gas appears to be seeping from in between the pressed in jet itself and the carburetor body!
Does this seem plausible?
It would explain why I can't lean out the mixture. I am thinking that sometime in the cars past the carbs were rebuilt and new jets pressed in and they scuffed the bore and the jet now is not sealed against the bore.
Is there any help for the carburetors or are they trashed? /ubbthreads/images/graemlins/frown.gif
Thanks in advance for any input.
RomanH

 

[arbs_53]

Roman,
During this past summer, I had spoken to Jeff Palya (Paltech1@hotmail.com), someone I had heard about through another Triumph forum who rebuilds Strombergs, and he mentioned that on my TR250, which has fixed jets, that it is sometimes possible to press out the jets, but one runs the risks off egging the carb body. That's something that may have happened here. It may be possible to replace the float chamber, plug and jet with parts from a used carb, but I would contact Jeff to get an experienced opinion.

 

[Rick O.]

Yes, the jet is a press-fit, but that has nothing to do with your fuel problem. Your float needle valve is either damaged or stuck open. Are you certain you adjusted the float height to spec (17mm I think)?

 

[AltaKnight]

Hi Roman....
It's taken me best part of the whole year fiddling with my twin ZS carbs to get the mixture just right so the plugs are a perfect tan colour.
The reason mine couldn't be leaned out enough was the float level was too high.
I adjusted it through trial and error because the book setting didn't seem to work properly. I even developed a way of removing the float bowls with the carbs in situ to check/adjust the fluid levels.
I'm fairly sure your problems are related to float height and you should try checking that before you do anything more expensive. /ubbthreads/images/graemlins/nonono.gif

 

[sammyb]

I've been doing the same thing as Graham on my TR3...totally leaned-out and the car was still rich -- turned out to be the floats. Of course, now the car is too lean, so I'm trying to bend the float levers back up to the right levels.

 

[RomanH]

I want to thank everyone for all of their help!
I thought I had the floats adjusted to the right level but I might have gotten it wrong. I did have an issue with one of the "new" needle valves sticking so I ordered some Grose jets. When I get those in I will start to play with the float levels again and see what happens! /ubbthreads/images/graemlins/hammer.gif