My Sunny has just an A12 with a standard carby. It's got a set of 4into1 extractors & an n12 distributor. Recently it's lost all power in the primary circuit. I've cleaned the carby using an ultrasonic cleaner & carby spray, so I'm pretty sure the primary circuit is clear. It'll idle, will move off using the idle circuit, won't move off if you open the throttle onto the primary circuit, then if you use full throttle it'll go 'like the clappers', usually almost into the back of the car ahead of you. Does this sound like a blown power valve, or could it be a blown head gasket causing insuficient vaccum to make the carby work until the secondary. Part of the carby top that the rod screws into has broken off & I assume it's gone down the inlet manifold.
Can anybody confirm about the power valve, as this is the second carby thats gone on. the new one was made up from parts from the Shed, so the second one could be a dud, too.
This is the car I drive to & from work & there's a real bastard of a hill start just up the street from work. You never get through the lights first go & you get it both ways. The problem with the carb makes this hillstart a real clutch breaker, so I'd like to get it fixed. Any help would me much appreciated. Please Email me on rob1@tech2u.com.au with any suggestions, within reason, as well as posting here, before I just throw an A15 with a DFV weber into it & be done.

you should be able to see the fuel squirting into the primary as you turn throttle by hand, this will at least ensure fuel is getting in

chokes not stuck shut? or secondary stuck open?

Good ideas, always start with the basics.

I agree, just throw an A15 with a DFV weber into it & be done.

most likely stuck power valve this was my problem they kept jamming so no power on primary until the secondary's open. I just gave up and put on a weber 34 ADM. I will never look back to the Hitachi carbs.

lol... its like a life cycle... i'm sworn to never go back to a weber/s

my favourites are hitachi SU's but injection is the ultimate of course

The Chokes not stuck, because sometimes pulling the choke out slightly cures the misfiring, but the next time it doesn't. The secondary's are also fine, except I wish that I'd gotten rid of the vaccum flap in the secondary's when I had the chance. Is there any test of power valves to see if they're good, cause I don't think they come with a recondition kit. I've got a couple of them around, going by the carb bodies in the Shed. If I can get home tomorrow before dark (supposedly a 2pm finish, even though I'm supposed to finish at 1:30 pm) & they're not replacing the telegraph/power poles in the street (eight trucks & some utes) I'll have a go with the compression tester & vaccum guage to see if it's the engine. Couldn't be the ignition module on the Pulsar distributor, as that'd just fail. Should swap the original module back in instead of the aftermarket one, I've always thought it had a weak spark.

PS at the moment I have 3 32/36dgv's, 2 32dgv's, 2 32dfv's & a 32dfe. Should be able to find a good one out of that lot.

After spending 4 hours yesterday afternoon trying to trouble shoot this, I'm still stumped. Put a vaccum guage on it, which sat rock solid at 21 inches of vaccum, blipped to 5 then out to 25, all like the instructions said it would. So, no blown head gasket, no damaged or burnt valves, no worn pistons or rings.
Onto the carby itself. I found another power valve, tested it to see if it open & shut, then installed it. I flushed out all the galleries with carby cleaner again. When reassembled it the engine started right up. While looking down the carby's top with a torch, I noticed that instead of the pump jet squirting through it's little nozzle, it was coming under the top gasket, running down the throat & the engine would hesitate. I then replaced the top gasket, the pump jet diaphram & checked that the nozzle was clear. It was clear, but it narrowed down towards the end, maybe to vapourise the fuel. So I took it for a good drive & everything seemed good. I used the vaccum guage to get the best idle vaccum. Problem fixed......
Got up this morning to go to work, 6 am car won't fire up. Pulled the choke, choke cable came off the nut, so no choke. Plus it sounds like it's flooded. I didn't have time to checked under the bonnet, but I reckon that pump jet problem wasn't fixed. Maybe the nozzle is part blocked & the fuel shoot backs up & blows out were the gallery with the check weight in it sits. Real pig to drive, cause everyone thinks you're racing them & get in the way. I was very lucky as I'd sort of resigned to just cruising along as best I can, being 5 minutes from work, when I passed a police car booking somebody. It's a 50k zone, but we're all usually doing 60-70k's. Drove over the next hill & here's a second police car with radar. Talk about a good choice to just slow down.
Couldn't look at it after work, because they lock the car park 5 minutes after the knock off bell on Saturdays & I didn't want to get locked in. I got it home about 12 Midday, had some lunch. As the motors OK, I'm chosing to keep it for now, but I started stripping down & cleaning the 32DFE carb that Im going to put on it tomorrow. The carby came complete with a manifold, so I'm just going to swap manifolds. I've jetted the carby for a 1300 Escort GT like the weber book said, which was what was in it. It's a good thing I did the strip down, as most of the jets & the needle & seat were blocked by mud. The kitchen still smells of carby cleaner.
Whats the odds that I'll get it running perfectly tomorrow but it'll refuse to fire Monday morning when I try to go to work. Where I work, if you don't have a good reason for taking Monday off, they don't pay you for Saturday either.
So heres hoping I get it close enough tomorrow so I can drive it to work Monday. I don't want to have to borrow my Aunt's TP Magna, but maybe I'll have to. Better put a smiley face in there, to take the curse off the Magna comment .

5 min drive to work is a 20 min walk..... Maybe 30.

I live 10 K's west of Parramatta & work at Mortdale which is almost in the Shire, a good 50 minutes drive, a bad 90 minutes because of the Hume hwy. I was just five minutes from work when I saw the first mobile taxation office. The only time I've ever lived close enough to my job to walk there, I was a Shi(f)t Supervisor for a Pizza delivery unit, & who wants to walk home at 1am in the morning.
If this carby swap works, I will joyfully & wilfully stick to the speed limit, except for the hill out of Yagoona on the Hume Highway, which is a real blast.