New Zealand Datsun Club

Did you replace the accelerator pump and test it?
Causes bogging down when driving away from standstill.

I actually ended up putting the old one back in (as I was suspecting the new one of causing the leak....). will stick the new one in and see what happens. Cheers!

Stick the new one in, it wont cause a leak.
Throw the original away.
I like rebuilding these carbs, and have experienced some the issues that turn up unexpected.
Ive accidentally fitted the airbleeds in their wrong places and had running issues.
Depending on the condition of the motor, you may need to upgrade the primary main jet. My sunny coupe A12 motor still played up after I did a full freshen up of the carb, as the motor is unknown mileage the resulting improvement was a 100 jet in the primary, instead of the 97. Made the difference, and all the frustration was gone. Must be a lazyish worn motor, goes well and seems fine for a random A12.

sweet cheers. will do fuel pump and report back

checked dwell and timing, dwell was way to high, dropped it to withi spec, reset timing to ~7 degrees at idle (hmm just remembered I didnt take of the dizzy vacum advance, shouldnt do uch at idle anyway).

did fuel pump, cleaned out pcv valve (when I blow into it now it actually seals) and found a crack in the hose from the valve to the block, right where it connects to the valve. didnt have any hose the right size so tape and a better hose clamp will do the trick for now. also the nuts holding the carb down wherent very tight.....wooops. reset the mixture as well. I think Ive got it pretty good as before the car would die if you gave it any choke (which means it is too rich as the choke makes it richer), and now it increases the reves if you put a bit of choke, but fll choke makes it run like shit/die.

all this seemed to has helped more, definitly idles smoother. havnt driven it but it 'seems'; a bit more peepy from idle when revving.

cheers again, much appreciated!

well done, hope it works

right, is running a lot smoother which is good.

Im sure something still isnt quite right though and it is quite sluggish in low revs (till about 2000rpm) and then is fine. super smooth and no stumbling or missing or anything, just seems far too sluggish. can almost feel it open up a bit above 2000rpm.

My drive way is inclined, relativly steep, but it only just crawls up it with foot flat on the floor. same when moving off from standstill, foot dead flat, not mch untill about 2000rpm then its fine.

timing is 7-8 degree at idle (750rpm), dwell is 51ish (spec is 49-55). mixture screw is set basically in the middle of it running worse (too rich or too lean) which is about 1.5 turns out from all the way in (says 2 turns out is a good starting point). is there a better way to set the mixture?

any thoughts? I thought of fuel filter but its fine once it has a few revs so decided that wouldnt be it.

cheers

ive had to shag around with my carb today, and the air mixture/idle screw needs to be about 4.5 turns for mine to run properly, however if it hardly runs/drives below 2000 rpm i would guess that this is the point where your vacum secondary is opening up and allowing fuel to flow through, so possible blockage on the main jet would be my best guess

yeh I was thinking it will be related to the secondary.

guess I should pull it apart again....fun times haha.

its odd that it runs so well at idle and what not, just when the load is on its real boggy. but yeh, could well be jet related. might swap back to the old jets if I dont find something obvious

You changed jets? Are they in the correct port? Might be muck in jet, have you tried the old revs on hand over carb clean out? Is trans slipping?