This pump is still sealed. I recall installing it 20 odd years ago when the car was running . It probably has 3K mi on it.
It’s on an SU work stoppage at the moment.
On the bench, hooking directly to a battery it is not running.
Instead of taking it apart, Exactly where do I smack this thing to resuscitate it?
The diaphragm is wedged between the aluminum section at the bottom and the painted section. Tap around there, lightly.
If it’s on the bench, you should at least pop off the plastic cap and inspect the points.
looks pristine.
12.7 volts in and 12.7 volts out but, still not moving.
can move diaphragm with thumb.
Points do not look burned, arm moves freely.
applying power and moving “point holding arm” manually does not make it run either.
sprayed some contact cleaner.
Now applying power will reliably get one click, tapping the hot lead on and off will move it on and off.
Occasionally, I can get it to run a bit, but slowly…puk…puk…puk instead of pukketapuketta.
I suggest you file the points to take off any corrosion. That may be the problem.
Dennis
69 OTS
OK, now I have filed the points and with he two halves separated I can get a lil quicker puk-puk-puk-puk.
But when I put the two halves back together I and touch the hot to battery I get single puts.
Sounds like you contacts need replacing ….buy a new set they are not expensive
When you put it back together, you need to set it up so the diaphragm movement just triggers the points as to flip as per the manual.
Basically you screw in the diaphragm, testing each quarter turn to see if the points trip when fully pushed in. When you get to the point where the points do not trip, you then back off to the nearest hole, then a further 2/3 turn.
Dennis
69 OTS
What Dennis said. Also, any SU pump manual makes it very easy to follow.
Either your contacts don’t break or they don’t get to make contact well enough. Probably the latter.
but why does it run better when the halves are apart?
Probably because the diagraphm has more freedom. Or is pushing in less. Play around a bit and you will make quick progress.
I believe you will need to shorten the distance (screw the diaphragm in) in half turns and then just check repeatedly. If it gets worse, try the other way obviously and always observe what the mechanism at the points does.
Don’t overtorque the bakelite when reassembling.
this was a barely used pump that sat for 20 yrs. But was working fine when removed from car 20 yrs ago and why it would need the diaphragm adjusted now, I don’t understand. Unless the diaphragm just go stiff and too hard for the pump to move it.
It’s a rubber part, rubber tends to age with time especially when exposed to gasoline. If the diaphragm looks fine, make the adjustment according to the manual and you should be good for another 20 years.
Agree with setting point "throw-over. I would also replace the diaphragm. They get stiff with age. I doubt the points themselves need replacing. Look at them under magnificatiion. Unless cratered, with spike and crater, will work. Sliding some fine sandpaper and working it around will probably be enough.
My diaphragms weren’t stiff at all and they were original, I still bought new ones and kept the old ones as spare - and if I‘m not mistaken I fixed another pump with some of the parts. Probably depends on exposure to ozone, etc.
Points sets are available spare but I bet this pump is just fine with a little adjustment. The diaphragm will change over the decades and that could be enough to change the throw.
OK,
I have cleaned the points.
checked the gap at both relevant places.
I have unwound the diaphragm until it fell off. (sob getting that back
I also “ruggled” the diaphragm as the manual suggested.
it still doesn’t work.
But, I found, with just the diaphragm half on the bench if I put 12 volts to it…nothing. Unless, I simultaneously press UP on the diaphragm…then it runs as long as I hold it. But If I put both halves together it won’t run.
So what does that tell me?
I will try this again tomorrow.
No one told you to completely unscrew the diaphragm!
Now you have to teach yourself how far to get the diaphragm in as a starting point. It’s not that hard.
didn’t say they did.
However, if it is not throwing over one is supposed to unscrew one hole at a time until it does. It never did start and then it disengaged.
And if you think putting that shaft into a blind hole with a rotating nut at the end which you cannot see and against spring pressure is easy…try it in the year after you had thumb arthroplasty in both hands. I did.
Can you explain why it works when I press up on the diaphragm but not otherwise?
OK, here’s where we are
I screwed the diaphragm in until it did not tick over. Backed off to nearest hole then, backed off 4 more holes per directions.
Then I powered it up holding the top i in my hand and it seem to run fine: pukapukapuka. So, I reassembled the two halves, powered up and it would not run!
I separated them twice and backed off one slot each time. Each time it ran while separated but not when together.
So, if anyone could explain what to do next, I would be glad to hear it. 
