Dual Kadrons with 1776.. where to start and how to sync

[legbuh]

My newly acquired 64 beetle with dual Kadrons, cam, and 1776 motor is running good, except for a few things.

1. It starts and runs very low RPM. Requires a small crack of the throttle and then a little revving for a few seconds to keep it going and warm enough to where it will idle (very low).

2. When warm, the RPM will be higher, but if you sit idling it will drop the idle down eventually. It hasn't stalled yet, but it sure seems like it wants to.

3. Starting from warm is hit or miss. Best to just barely crack the throttle.

4. Hesitation going from cruising speed and putting the pedal down (for example to go around a tractor that's hogging the road). This I assume is an accelerator pump issue.

5. Overall smoothness and "pep". Seems a little doggy. It did come from florida to MN so I'm sure elevation and ambient temps make a difference.

So, what I want to do is:

1. Set the idle mixture. I did a quick check on the left carb (easier to get to the mixture screw) and it's about 1.3 turns out.

2. Sync the carbs. I have a 4 port manometer I use for 4 cylinder motorcycles if that will work. I just don't know where to put the hoses or what to use to sync them.

3. Adjust the accelerator pumps. Looking at how the operate now it seems like the one on the right is moving twice as far as the one on the left. Even the treads showing are at least double on the right.

So, what I'm interested in is:

1. The order to do these things.

2. Where to put my tubes from my manometer to sync and what to turn to sync them (it's been a long time since I did that).

3. Determine if the accelerator pump arms should move in unison and the same distance.

Thanks!

[57BLITZ]

Here's a video that might be of interest to ya . . . https://www.youtube.com/watch?v=PGmPqyydCMs
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[legbuh]

Yep, watched that 3 times already. The only thing that isn't there is balance with a manometer and where it goes in the order.

Normally I would balance, set mixtures, set idle, set timing and balance again.

I may just start with the idle mixtures. Fun fun.

[rcooled]

[legbuh]

Thanks, Rcooled! Appreciate the info.

[legbuh]

Well, I started out by trying to get the idle screws and acc pumps set the same... which is pretty much impossible from the engine bay. So I took the carbs out (was surprisingly easy.. thank goodness).

I've done a lot of carb work in the past but on motorcycles. So it wasn't too daunting of a task. And there are a couple good vids on youtube to tell you where everything is.

The first thing I noticed was the right side carb's acc pump adjustment was WAY in with a wire tie in front of it. Exactly what the expert in the video said was a NO NO.

The other carb wasn't screwed in as far, but also had a wire tie acting as a spacer.

Removed the wire ties, set them both at approx 6mm of travel (which is what the video said is a good starting point for a 1776).

I then took it all apart, cleaned all the jets, etc. Good news was I have plastic floats, not brass. If I would have had brass I would have just stopped and ordered the new floats.

I checked all the jets, venturi, etc and wrote down their info for future reference.

Set the idle screws at 2 out and reinstalled. Once the fuel filled the bowls she fired right up. Played a little with the idle screws and ended up at 1.5 turns out. Idles great, doesn't idle down after a bit. Did some quick revs and it didn't bog down and was more "peppy" sounding. Just a touch of black smoke coming out each pipe. I probably can turn the acc. pump down a little.. but it wasn't that bad at all.

Then a drive. Oh wow.. it was like a new machine. Didn't pop, backfire, bog or anything. Felt a lot more peppy.

Got home and let it idle again for a few minutes and it never bogged or changed idle speed. I'd call this a success!

[andk5591]

Almost done - Now that it runs, you can really dial it in.

Use your manometer to synch using the ports fr the crossover tube in the manifolds. I built my own manometer and it works very well.

Look at Kaddie shack and AJ Simms tuning procedures

You need to verify that your acel pump nozzles are not siphoning fuel at higher RPMS - get a flashlight and look down the carb bores as you come up above 25 RPMS... You are watching for fuel to stream or drip from the accel pump nozzles. If you have the prob, bend the nozzles up a bit and reaim them.

What jets are you running by the way.
_________________
D-Dubya Manx clone - 63 Short pan,1914.
Rosie 65 bug - My mostly stock daily driver.
Woodie 69 VW woodie (Hot VWs 7/12).
"John's car" 64 VW woodie - The first ever
Maxine 61 Cal-look bug - Cindy's daily driver.
Max - 73 standard Beetle hearse project - For sale
66 bug project - Real patina & Suby conversion
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[legbuh]

I apologize for not responding earlier. I didn't get a notification for the reply for some reason.

Here were the specs:

Idle Jet: 65
Main: 130
Venturi: 40-28
Air jet: 150

Everything is running good so far. Plan on getting new plugs and doing some reading there.

[andk5591]

Unless you have the siphoning accel pump nozzle, you are kind of small on the mains. (and if you do have the siphoning, fix it). Just checked my log book. When I was running a 1776 in the buggy, was using 137.5 mains. This was dialed in on a chassis dyno. I did have bigger valve heads. I dont remember the idle size, but usually run a 55 or 60.

We also tuned a buddys 1776 with what I think what were stock heads and ended up with the same size mains. In both cars, ratio rockers were used.

I would suggest jumping up at least to 135s. I think you will notice a difference.

Oh - and bump up the idle speed. You will find that the experts tend to run it at least at 1000. Will idle much smoother. At the speed you are at, you can pull one plug wire on each side and it wont change much if at all.
_________________
D-Dubya Manx clone - 63 Short pan,1914.
Rosie 65 bug - My mostly stock daily driver.
Woodie 69 VW woodie (Hot VWs 7/12).
"John's car" 64 VW woodie - The first ever
Maxine 61 Cal-look bug - Cindy's daily driver.
Max - 73 standard Beetle hearse project - For sale
66 bug project - Real patina & Suby conversion
There's more, but not keeping them...

[legbuh]

Thanks for the info. I'll have to dig through all my jets to see if I have that size. (I have a ton of mikuni and keihn jets that I believe should work).

I have the idle set so when it's warm it's around 900. Cold it idles lower and lumpier (no choke I assume is why).

[andk5591]

Correct about cold and no choke. Cruise through Kaddie shack and AJ Simms Kad tuning procedures and you will see that both endorse a higher idle speed. If you have a IR thermometer, check the exhaust temps at idle and you will see one cylinder on each side is way cooler than the other. Bring up the idle a little, which will smooth it out and the temps will be much closer.

Charge robbing effect due to firing order and single barrels.
_________________
D-Dubya Manx clone - 63 Short pan,1914.
Rosie 65 bug - My mostly stock daily driver.
Woodie 69 VW woodie (Hot VWs 7/12).
"John's car" 64 VW woodie - The first ever
Maxine 61 Cal-look bug - Cindy's daily driver.
Max - 73 standard Beetle hearse project - For sale
66 bug project - Real patina & Suby conversion
There's more, but not keeping them...

[legbuh]

I will do that... I have an IR temp guage from the old RC days.

So should I shoot for 1k cold rpm (which means a little higher when warm) or 1k when warm?

[andk5591]

I run where it seems happy. Usually around 1000 to 1100 when warm. I have Kads on 3 of our own cars and have installed quite a few on customer cars. They all seem to like this, but I remember talking to AJ Simms about this quite a few years ago and he sets some up even higher.
_________________
D-Dubya Manx clone - 63 Short pan,1914.
Rosie 65 bug - My mostly stock daily driver.
Woodie 69 VW woodie (Hot VWs 7/12).
"John's car" 64 VW woodie - The first ever
Maxine 61 Cal-look bug - Cindy's daily driver.
Max - 73 standard Beetle hearse project - For sale
66 bug project - Real patina & Suby conversion
There's more, but not keeping them...