K
kcorbin
Guest
Here's a picture of my homemade manometer. It's similar to a design I saw on the 250 ninja site for a 2 cylinder but adapted to a 4 cylinder engine. If it's not clear from the pic, the tube to each cylinder *just* goes through the stopper while the tube to the other bottles goes all the way down to the fluid.
*update* Apparently there's some confusion as to ultimately how this works so I'm clearing it up here. The fluid fills up the bottles and never goes up the tubes to the cylinders. If you fill each bottle less than 1/4 full, even if all the fluid from all of the bottles is sucked into one bottle, the strong cylinder will only suck up *air*. You check the levels in the bottles, not the tubes in any way; I set mine on a 2' step ladder to watch it while adjusting cylinders. Also, because you have the volume of each bottle involved in the vacuum, there is no need for restrictors or anything like it to reduce the amount of vacuum or smooth out the vacuum pulses.
I used Lipton iced tea bottles I recycled from co-workers and the tubing, tees, and rubber stoppers all came from Ace Hardware (less than $20 I believe). The 'fluid' is just distilled water with blue coloring; no need for oil or ATF with this design although they would work just as well. The water doesn't even need to be distilled water but I wanted to avoid any deposits later on and I had plenty left over from my battery.
The port adapters are the 5mm hex screws from my old intake boots as my new ones came with them. I simply drilled them through and then soldered a piece of 3/16th brass tubing on to the head. An 18" piece of tubing was like a $1.35 at Ace again and the vinyl tubing slipped over it perfectly.
The pros: With the correct starting level of fluid you never have to worry about sucking fluid into the cylinder. You can synchronize fully taking into account the interaction between all the cylinders; after seeing this in operation, I don't see how syncing, say 1-3, then 2-3, then 3-4 is really going to give you the best sync. There's no 'pulsing' to worry about as the design smooths out the vacuum across all RPM ranges. It's cheap. It gives you the chance to fabricate (my wife likes to say 'makeshift'!) something.
The cons: If you have a cylinder that's way off then you can suck a bottle dry before you get it adjusted enough to settle down. This could be alleviated by using a more viscous fluid like oil or ATF and/or using bigger bottles to allow for a greater volume of fluid. It really wasn't a big deal though to just cut the engine, pull the tube from the port adapter on the bottle that was full, and blow until the air was out of the system and the bottles were leveling out again. Once I was close though, using a thinner fluid really helped make it easy to see minor adjustments quickly.
Never having done this before, I was amazed at how tiny adjustments made a big difference between the cylinders. I was turning the screws a 16th of a turn and seeing a rapid shift in the levels often times.
*update* Apparently there's some confusion as to ultimately how this works so I'm clearing it up here. The fluid fills up the bottles and never goes up the tubes to the cylinders. If you fill each bottle less than 1/4 full, even if all the fluid from all of the bottles is sucked into one bottle, the strong cylinder will only suck up *air*. You check the levels in the bottles, not the tubes in any way; I set mine on a 2' step ladder to watch it while adjusting cylinders. Also, because you have the volume of each bottle involved in the vacuum, there is no need for restrictors or anything like it to reduce the amount of vacuum or smooth out the vacuum pulses.
I used Lipton iced tea bottles I recycled from co-workers and the tubing, tees, and rubber stoppers all came from Ace Hardware (less than $20 I believe). The 'fluid' is just distilled water with blue coloring; no need for oil or ATF with this design although they would work just as well. The water doesn't even need to be distilled water but I wanted to avoid any deposits later on and I had plenty left over from my battery.
The port adapters are the 5mm hex screws from my old intake boots as my new ones came with them. I simply drilled them through and then soldered a piece of 3/16th brass tubing on to the head. An 18" piece of tubing was like a $1.35 at Ace again and the vinyl tubing slipped over it perfectly.
The pros: With the correct starting level of fluid you never have to worry about sucking fluid into the cylinder. You can synchronize fully taking into account the interaction between all the cylinders; after seeing this in operation, I don't see how syncing, say 1-3, then 2-3, then 3-4 is really going to give you the best sync. There's no 'pulsing' to worry about as the design smooths out the vacuum across all RPM ranges. It's cheap. It gives you the chance to fabricate (my wife likes to say 'makeshift'!) something.
The cons: If you have a cylinder that's way off then you can suck a bottle dry before you get it adjusted enough to settle down. This could be alleviated by using a more viscous fluid like oil or ATF and/or using bigger bottles to allow for a greater volume of fluid. It really wasn't a big deal though to just cut the engine, pull the tube from the port adapter on the bottle that was full, and blow until the air was out of the system and the bottles were leveling out again. Once I was close though, using a thinner fluid really helped make it easy to see minor adjustments quickly.
Never having done this before, I was amazed at how tiny adjustments made a big difference between the cylinders. I was turning the screws a 16th of a turn and seeing a rapid shift in the levels often times.
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