Carbs set full lean, still running rich

[bkelly]

The floats/needle valves are brand new so they aren't defective. I'll try to adjust them later on today. If this doesn't work, there's a guy that can work on them, but he's almost 2 hours away. He also welds so if it has to go that far the floors might as well be fixed (need some small patches) and the 1/4 will be replaced with a donor. I just hope this simple running rich problem doesn't lead into an all out restoration. I'm sure everybody has had the "While we're doing this, we might as well do that" syndrome.

[geezer]

Here's how Nissan suggested adjusting floats.

[Friar-Tuck]

BK,

I had an extremely rich condition due to the fact my #1 carb jet was well below top of the carb body due to the fiber/washer it rides in had never been run fully up in the lean position. I had to soak it in WD-40 a few hrs to soften it and (with difficulty) run it up full lean and then back it out 2 turs to start tuning. Is the distance from the carb body to top of the jet approx. the same distance in both carbs?

I had to remove the carbs and dissasemble to finally track down that gremlin.

Have a peek down the body at the jets and see if they are approx the same distance down the body from the throat.

The tail end of a caliper might fit between the carb body wall and the jet or...

even the little red spray straw from a can of WD and a small sharpie to mark the "straw" with.

Good Luck,

Tuck \o/

[justin260z]

i found out my carbs have 2 different sized jets. Where can i purchase new ones?

[e_racer1999]

jets or nozzles?

[justin260z]

the things that screw into the top of the bowls.

[Arne]

i found out my carbs have 2 different sized jets. Where can i purchase new ones?

Seems to me that that was normal for some years of roundtops, '72 three-screw I believe. But don't hold me to that.

[JimmyZ]

Here's how Nissan suggested adjusting floats.

Nice Geezer! I like stuff like that! Was that out of an FSM or another publication?

What caught my eye was that the fron and rear carbs had different heights. Beats the sh!# out of the Haynes manual. Thanks.

Jim

[beandip]

the things that screw into the top of the bowls.

justin, as long as the needle valves are not leaking it doesn't matter if these are different is size. We hare talking about the float shutoffs. There are different styles some have a little brass stopper with a rubber seat. I have seen some made out of glass. As long as the valves stops the flow of fuel when it is supposed to , this is all that matters. Nozzles and needles in the carb body , this is a whole different matter.

[Arne]

i found out my carbs have 2 different sized jets.

What caught my eye was that the fron and rear carbs had different heights.

Different float heights to match different needle jets, I suspect.

[geezer]

Nice Geezer! I like stuff like that! Was that out of an FSM or another publication?

What caught my eye was that the fron and rear carbs had different heights. Beats the sh!# out of the Haynes manual. Thanks.

Jim

Jimmy, all 4 attachments I posted were from a single Technical Bulletin that was issued in Feb. 73. The specs differ from what was printed in the FSM's, because the feedback from hundreds of technicians worldwide was now known. This was the recommendation that was sent out to the dealers. The insert with the gauge cutout is a stiff cardboard.