TOPIC:

Hey,
I have been checking out some carb synchronizers and they are outrageously priced in Canada. I was looking in a flyer for Princess Auto and they have a SAE/Metric Vacuum/Fuel Pump Tester rated at 0-10 PSI(10-700b/cm) and 0-30 in-Hg on sale for $10 each, and come with the guage and hose. My question which I am sure somebody will know the answer to is, if I buy 4 of these can I use them to synchronize the cabs on my 78 KZ1000 after I rebuild the carbs? If you need more info on them their web site is www.princessauto.com or the link is.

www.princessauto.com/_osn.cfm?CTRY=CAN&o...L%20%20PUMP%20TESTER

Thanks
Wamphyri

I use something similar, they come as a set.


tinyurl.com/2d8jy5

Post edited by: mariozappa, at: 2007/01/19 13:01

That's interesting Wamphyri86. On sale at $10 each is a good price. I can see where you are coming from. The only questions I would have would be on the hose. Can you cut it and would it fit over a vacuum nipple and would you need to put dampers inline ?
You could probably make it work.

I got a Carbtune a few years back (www.carbtune.com)and will swear by it. Ordered online and took 5 days to come but it did cost $100.

If you try it let us know how it works. I would hate the thought of messing about with mercury manometers.

Post edited by: JR, at: 2007/01/21 17:02

I use one vacuum gauge with a brass fish tank air valve setup with 5 connectors at the top (1 for the gauge & 4 for each of the cylinders). You'll need to plug the ends of the valve setup. The one in this picture only has 4 connectors.

Something I forgot to add was that you can tweek the valves to keep the needle on the gauge from jumping all over the place when syncing your carbs.

When you construct a manometer, you have to be sure that it dampens the pulses and gives you a smooth average-reading. It's a dynamics problem and not static.

As JR mentions, a dampener is needed. This is created by a pinhole restrictor at the point where the hose connects to the manifold port. The pinhole, along with the volume of air in the tubing act as a dampener. You want the hoses to all be the same length (more precisely, the volume of air in the hoses must be equal), and the pinholes need to be calibrated.

You calibrate the pinholes by temporarily connecting all four hoses to the same vacuum port using a 1-into-4 manifold pipe (available at any parts store for washer fluid etc). All four hoses should give the same reading since they are hooked up to the same source. If one hose has a low reading, you open its pinhole slightly. It takes a little practice to get it all right.

The only problem I see with using one gauge to read four ports is that the reading often changes from second to second and changing the ports over will change the reading since each one will introduce a small blip of air during the transistion.

Post edited by: loudhvx, at: 2007/01/19 21:15

You're probably right loudhvx, but I've been syncing my carbs using this method since 1979 with very good results.

Havn't you guys gotten good enough to synch. carbs without the gauges.

STOP! I,m off topic. This has been a test......

i bought a set of gauges from jc whitney just got them in today..4 gauges hoses, 4 dampning valves plus 4 brass tubes with the pin holes in them..i'm still trying to figure out why valves and tubes..LOL..only 48 bucks for all..can send pic if u like

i bought a set of gauges from jc whitney just got them in today..4 gauges hoses, 4 dampning valves plus 4 brass tubes with the pin holes in them..i'm still trying to figure out why valves and tubes..LOL..only 48 bucks for all..can send pic if u like

Sounds like the same set I got. The brass pipes are for Suzuki or Honda, I think, or maybe for the KZ400 carbs.

There should be 4 plastic plugs with pinholes in them. Those are the restrictors. They should go in the tubes near the carburetor end.