The DT250B/400B service manual states a distance of 17.3mm(+\-2.5mm) between the float arm and the gasket seat, but whe I set it to that, the float arms are at an angle which doesn't seem correct???
I'm guessing the manual has the incorrect measurement and the arms should be 'about parallel' with the carb body (which is about where they were before I changed them - and which would align with the photo in the manual). Arghhh...
Anybody else had this issue? Is there a measurement which is known to be correct or should I just make the arms parallel to the carb body?
Many thanks...
The DT250B/400B service manual states a distance of 17.3mm(+\-2.5mm) between the float arm and the gasket seat, but whe I set it to that, the float arms are at an angle which doesn't seem correct???
I'm guessing the manual has the incorrect measurement and the arms should be 'about parallel' with the carb body (which is about where they were before I changed them - and which would align with the photo in the manual). Arghhh...
Anybody else had this issue? Is there a measurement which is known to be correct or should I just make the arms parallel to the carb body?
Many thanks...
  

While I'm on a roll.... The manual states the jet needle should be on clip position 3 (from top). Does anyone know if that is correct? I'm trusting this manual less and less.....

I'm sure the standard factory position was position 2 (from top)

Mark T and others discuss and answer here: yamaha-enduros.com/index.php/forums/74-7...8-1976-dt-400#115000

I also posted a chart to show the conflicting information and the sources.

Float level should be 23mm +/-

As MarkT has mentioned on the forum previously, you can't go far wrong if you keep the arms paralell to the float chamber. If you move them manually, you should be able to see the valve close at this point.

parallel is good or good starting point if no info to go by. I do see though that ya measuring it at the tip. I measure it where the float pins strike. Not even sure why, but always done it that way without thinking. Measuring at the tip accentuates any measurement past parallel if i’m thinking right. Umm I think haha. Cheers.

From memory, in my carb the needle valve sitzs much deeper in it´s thread hole as yours. Maybe you have the wrong Copper washer under the valve? The orig washer is very thin and sits down in the hole. yours seem to sit on top of the bore

Hi - there is only a very thin fibre washer (red) under tha valve. What looks like a thick brass washer is part of the valve...
 

Don't take this the wrong way, but...those parts still look pretty dirty. Imagine what the small passageways look like inside where you cannot see them if the outsides of these parts look like that where we can see them.
I'd clean the carb again and run some serious air through all the internals as well...
Just sayin'.
But I agree with you on the red ring under the float set. That's about what they all look like.

Edit: One more thing. I'd put the floats on the arms before setting the level. You may wind up with a different reading without the pontoons on the arms than with.

The float level of the DT250 is 17.3mm, but for the DT 400, it´s 23 +- 2.5mm.