Datsun Bluebird 180B - Nikki carb fault?
Posted: Wed Jul 25, 2018 4:27 pm
The old Datsun has been misbehaving. It is a 1983 Bluebird 180B, 910 estate so with L18S engine, and a Nikki twin choke downdraught carb.
It was running really well a couple of weeks ago but had started running rough & lumpy after I refilled with fuel, especially between 2000-3000rpm. I have probably used all of that fuel by now but fault persists.
I had initially checked & cleaned the points - all well of course but no improvement.
Then after a further run I found the plugs were sooted & black. But the crank breather is dry (it doesn't use oil). When I peep down the air intake the choke flap is open (ie not restricting air flow) - I have already mostly backed off the auto choke. On a long run at the weekend, I estimate about 15-20mpg that is well out of sorts as well as out of my pay grade, and dropping to 2 or 3 cylinders as if flooded at times. Notwithstanding that it will sit and idle quite happily.
The float level is about midway up the glass peep hole (these carbs have a peep hole in float chamber - this indicates correct float level)
Anyway - took me a morning to get the carb off, and have now dismantled and cleaned and reassembled. It was spotless clean inside, and nothing seemed loose or perished so no fault found. But I am no expert.
However I have tried the car again but it is still running very very rich with a black sooty exhaust, and at least one black sooted (but not wet) spark plug. Seems to still run OK at idle, and moderately on 2nd choke.
I believe the carb is a 1983 NIKKI 21A304-341
Help!!
Who can help me?
Do you know of any carb gurus in or near Gloucestershire?
Thanks in anticipation ….
Ed
It was running really well a couple of weeks ago but had started running rough & lumpy after I refilled with fuel, especially between 2000-3000rpm. I have probably used all of that fuel by now but fault persists.
I had initially checked & cleaned the points - all well of course but no improvement.
Then after a further run I found the plugs were sooted & black. But the crank breather is dry (it doesn't use oil). When I peep down the air intake the choke flap is open (ie not restricting air flow) - I have already mostly backed off the auto choke. On a long run at the weekend, I estimate about 15-20mpg that is well out of sorts as well as out of my pay grade, and dropping to 2 or 3 cylinders as if flooded at times. Notwithstanding that it will sit and idle quite happily.
The float level is about midway up the glass peep hole (these carbs have a peep hole in float chamber - this indicates correct float level)
Anyway - took me a morning to get the carb off, and have now dismantled and cleaned and reassembled. It was spotless clean inside, and nothing seemed loose or perished so no fault found. But I am no expert.
However I have tried the car again but it is still running very very rich with a black sooty exhaust, and at least one black sooted (but not wet) spark plug. Seems to still run OK at idle, and moderately on 2nd choke.
I believe the carb is a 1983 NIKKI 21A304-341
Help!!
Who can help me?
Do you know of any carb gurus in or near Gloucestershire?
Thanks in anticipation ….
Ed