I want to make sure my carbs are synced up. I think they are fine but I just want to make sure. I know about http://www.carbtune.com/ but I was wondering if there is maybe a cheaper option then $100?
Yes, there are several. I made vacuum adapters from 3/16" aluminum tubing threaded on one end to match the intake vacuum ports. Then you can use a variety of ways to make tubing manometers with a fluid that will not harm if it is sucked into the engine (ATF). These can be a loop with vacuum attached at each end, and adjust until levels are equal.
I use a vacuum gauge with a large (1 quart) bottle in line with the gauge to act a dampener. I connect both vacuum ports with a T and alternately pinch off the tubes while adjusting the balance until the needle on the gauge does not move when switching from one port to the other.
I got a set of those on eBay for around $35.00. When I adjusted the carbs, I checked it against the Morgan Carbtune a friend has, and all was good.
A Mercury Motion Pro is currently listed on eBay for $20 shipping included. I wouldn't recommend ordering this one until the seller gets some feedback from the 17 that have been sold.
Thanks for all of the input. I'm guessing at this point just about every thing has already been asked haha. I tried to search some but when I search anything dealing with carbs so much stuff will come up.
Most would buy them as a set of two, just makes thing easier. This a real tool, not something from eBay and the 1% accurate gauges are graduated by 0.5 mm but easily interpolated to 0.1 mm due to the size of the gauge.
Huge gauges made in USA by Weiss, 1% accurate, glass gauge fronts that won't get scratched in your toolbox.
Solid brass fitting, sintered bronze snubber, accurate and repeatable enough such that you can measure the (left?) side then move it to the other side and adjust for the same vacuum at the same idle speed.
Gauges also mean no possibility of the fluid separating or the mess they and the home made ones can.
Not the cheapest method out there but it's a real tool built to last a lifetime.
1 years warranty, individually replaceable parts, just another choice and I'll be keeping a double gauge model around.
Marshall, your gauge looks great, but could you use a "T" connection valve to switch the reading from left to right? Only one gauge to look at and you could immediately tell the difference as you switched. A little more hardware but I think it may be better than a two gauge setup. Having the T valve at the base of the gauge and running two vacuum lines would be the setup I see working for me. Wadda you think?
I found them inaccurate,,, that is, when I measured the same vacuum using a calibrated vacuum pump each tube on the Morgan would read differently. Not only that but no repeatability. Each would read differently when disconnected then reconnected. They're supposedly adjustable but they acted the same after adjustment as before. When I wrote them about it (twice), they never answered. If your not interested in accuracy they're ok but IMHO they are sure not worth the money. For that matter neither are the Motionpro Syncpro. Same thing. The only ones I've found that were reasonably accurate was a set of old mercury filled tubes purchased 30 years ago from JC Whitney. The brand name has worn off. (Maybe K&L)
Rather than waste a lot of money on these new politically and environmentally correct tubes I recommend a Synchromate 2. Run about $200,,, BUT,,, hook them up, tweek the light to the center and your done. They are accurate and have good repeatability. It is also a reasonably accurate tach. IMO the easiest and most accurate I have found in 50 years...
I have nothing to do with Synchromate, its manufacturer nor do I sell these. Just an old school motorcycle mech...
Macmaster Carr sells vacuum gauges. I ordered 2 small 0 to 30 inch vacuum gauges for about $10 each. You will also need tubing and fittings. also you need a small hole to get rid of pulsations. I used a piece of 1/4 copper tube and kept flattening it with a vise grip until the pulses went away. There are probably better ways.
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