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Sun Jun 01, 2014 3:49 pm

I have been experimenting with the accelerator pump adjustment nut on my Kadrons (running 40s on a 1600 dp). From AJ's site, and from disconnecting the accelerator pump linkage from its throttle plate opening, you get a good idea of where the accelerator pump is in a neutral position, i.e., where it naturally rests against the diaphragm when the diaphragm spring is in its outermost position and there is no compression force being exerted on the diaphragm.

In this neutral position, where the accelerator lever is resting on the diaphragm and exerting no compression pressure on the diaphragm spring I would think that this is the baseline for adjustment. i.e., zero squirt.

According to AJ, you want to slightly preload the accelerator pump as an initial starting point, which means backing the adjustment nut off (counterclockwise) of the linkage so that when you attach the linkage to the throttle plate it is already in a pumped (preloaded) position, i.e., causing the accelerator lever to be depressed a slight amount to cause the diaphragm to compress against the spring and actually be slightly into the pump zone. This is how I set up the carbs preinstallation.

Now I have a lag at about 3,000 rpm that is not ignition timing relating that I am trying to tackle.

Here is my question. I see a lot of pictures showing a spacer between the nut and the lever on many Kadrons. This makes no sense to me as it would not seem to have any effect on getting the accelerator pumps to pump sooner, as these spacers between the nut and the lever would seem to move the lever further away from the neutral zone.

Isn’t the way to get a quicker squirt or solve a possible flat spot associated with the Kadrons to maybe start with AJ’s approach and then add one or more washers to the other side of the linkage (between the throttle plate attachment and the accelerator lever). Watching the operation of the accelerator pump it seems to me that it is this side of the linkage that has more impact on the timing and/or amount of the squirt during throttle movement.

I come to this conclusion because moving the nut up and down the linkage seems to have no effect on solving my flat spot that is associated with trying to accelerate at about 3,000 rpm. I suppose the other explanation may be jetting, but I feel that I am pretty close running the 130 mains and 55 idles given my near stock 1600 dp application.
All input greatly appreciation. Thanks, Grant

Sat Jun 07, 2014 2:47 pm

GTman wrote:
I come to this conclusion because moving the nut up and down the linkage seems to have no effect on solving my flat spot that is associated with trying to accelerate at about 3,000 rpm. I suppose the other explanation may be jetting, but I feel that I am pretty close running the 130 mains and 55 idles given my near stock 1600 dp application.
All input greatly appreciation. Thanks, Grant

Maybe your problem has not to do with jet squirts.
Have you tried to remove, clean (preferable with an air compressor) and reinsert the idle jets, before anything?

Sat Jun 07, 2014 3:03 pm

Look at Kaddieshacks site great info!!

Sat Jun 07, 2014 6:43 pm

Set it up so the pump jets squirt immediately and with a non sputtering flow thru the complete throw of the throttle.

Wed Jul 02, 2014 1:44 pm

This is exactly how I see it. I'm trying to reduce the accelerator pump squirt (volume) because my exhaust is full of soot, but the spark plugs say the mixture is fine (they're nice and tan), so this leads to the pumps squirting too much. In the adjustment, as you say, you unscrew the plastic nut (counter clockwise) to reduce the squirt - which is actually setting the "start" position of the pump travel "into" it's pumping range.

the way I had them set first, I had the adjusting nuts turned in (clockwise) until there the accel pump arm was slack (no pressure on the diaphragm). then i started backing the nut off basically until there was no slack in the linkage - this meant as the throttle started to turn, the pump was at the beginning of it's operating range, full volume.

as for the spacer, same thing. in reducing pumped volume, the adjuster has to be backed off, so the spacer can't be there... it actually needs to be between the lever and the pivot, to pre-load the spring.

newayz, this doesn't help your situation, other than if you set at max squirt, I think we're getting too much fuel or definitely not lean but I don't know if can cause your stumble at 3k or not. are you sure it isn't electrical...i had bad plug wires (solid copper) that I didn't realize until I changed them.

I don't know how far you are from the coast (i'm a few hundred feet, it's relative humid), but i'm using 60 idles because the 55s were popping occasionally off idle, that stopped with the 60s. I haven't had a problem anywhere above idle though.

GTman wrote: I have been experimenting with the accelerator pump adjustment nut on my Kadrons (running 40s on a 1600 dp). From AJ's site, and from disconnecting the accelerator pump linkage from its throttle plate opening, you get a good idea of where the accelerator pump is in a neutral position, i.e., where it naturally rests against the diaphragm when the diaphragm spring is in its outermost position and there is no compression force being exerted on the diaphragm.

In this neutral position, where the accelerator lever is resting on the diaphragm and exerting no compression pressure on the diaphragm spring I would think that this is the baseline for adjustment. i.e., zero squirt.

According to AJ, you want to slightly preload the accelerator pump as an initial starting point, which means backing the adjustment nut off (counterclockwise) of the linkage so that when you attach the linkage to the throttle plate it is already in a pumped (preloaded) position, i.e., causing the accelerator lever to be depressed a slight amount to cause the diaphragm to compress against the spring and actually be slightly into the pump zone. This is how I set up the carbs preinstallation.

Now I have a lag at about 3,000 rpm that is not ignition timing relating that I am trying to tackle.

Here is my question. I see a lot of pictures showing a spacer between the nut and the lever on many Kadrons. This makes no sense to me as it would not seem to have any effect on getting the accelerator pumps to pump sooner, as these spacers between the nut and the lever would seem to move the lever further away from the neutral zone.

Isn’t the way to get a quicker squirt or solve a possible flat spot associated with the Kadrons to maybe start with AJ’s approach and then add one or more washers to the other side of the linkage (between the throttle plate attachment and the accelerator lever). Watching the operation of the accelerator pump it seems to me that it is this side of the linkage that has more impact on the timing and/or amount of the squirt during throttle movement.

I come to this conclusion because moving the nut up and down the linkage seems to have no effect on solving my flat spot that is associated with trying to accelerate at about 3,000 rpm. I suppose the other explanation may be jetting, but I feel that I am pretty close running the 130 mains and 55 idles given my near stock 1600 dp application.
All input greatly appreciation. Thanks, Grant

Wed Jul 02, 2014 5:28 pm

I run kads on 3 cars - no spacers. And keep in mind that the little blast is not going to show up on your plugs. Too much squirt is as bad as too little. Try starting with the accel pump travel at about .160" and just use whats already there - no spacers or anything.

BUT there is more to your engine than the carbs. What distributor and what is your timing set at?

And I forgot - read this http://www.thesamba.com/vw/forum/viewtopic.php?t=398526&highlight=kad+accelerator+pump