Topic: Old mercury Motion Pro carb sync tool - whitout mercury...

[stou]

I had a bad luck this morning! The buttom hose at the back of my Motion Pro carb sync tool disconected and all the mercury went down. I know it is very hard to get mercury now. I just wonder if it can work with oil?

Anyone had this kind of problem? I searched but didn't found nothing on replacement fluid that can work other than mercury.

[ekpent]

 Wonder if automatic trans fluid would work ??

[MauiK3]

I’m pretty sure the tube lengths are unique to the weight of mercury. The tool might be a paperweight without mercury.

[beemerbum]

I hope you were careful with the spilled Hg. That stuff is highly toxic

[carnivorous chicken]

You can order it from Oregon -- there is a guy who makes the same style tool as the old Motion Pro mercury ones, and he sells replacement vial of mercury. I ordered it and received it when I lived in Boston -- I am guessing OR is more lax when it comes to selling the stuff, and wasn't sure that it would arrive in MA but it did, and the box had some kind of hazardous content labelling. Dig around and see if you can find it, if not I can try to look it up, although it's been 3-4 years.

[stou]

I don't think mercury will pass the border to Canada ;-)

I did a test with some light trans oil and I think it will work. I have a friend's bike to sync next week, I'll let you know if it work with light oil.

[Bodi]

It isn't the viscosity that matters, it's the specific gravity - mass per volume. Oil is lighter than water. Mercury is 13.6 times heavier than water.
Try whatever you like, but I believe no other fluid will suffice in carb sticks designed for mercury.
And be careful about the spilled mercury. Try and vacuum it up and then dispose of the filter bag. Technically it will be hazardous waste and illegal to toss in household garbage in pretty much any jurisdiction.

[70CB750]

Funny, i dont remember how many mercury thermometers i broke in my bed when i was a kid.

Nowadays, Americans would evacuate the whole house, because everybody knows that mercury kills on sight.

[Jerry Rxman Griffin aka MuthaF'er]

I agree. Pure paranoia.

[754]

 Someone should have some scrap mercury.
 Bad part is you can't just run an ad without drawing attention.
 Trying to think of a trade that used it a lot..

[pjlogue]

You might try a science supply house.

-P.

[Tracksnblades1]

If you want to split hairs. Water column manometers will work to sync with.
Howerever they tend to be tall if using u-tube type.
1" mercury= 13.609" of water

Or 13.595" seems to be a disagreement.

[jgger]

Might try scavenging some junk yards for under the hood light switches. They used mercury in those for quite some  time. Also heater thermostats for houses used mercury. Just a thought if everything else is a dead end.

[awrawr]

I made my own set of water manometers. THe tube length for the open ended type would be impractical for water, so i bunged up one end, taking care to ensure all four were bunged up with an equal level of water (dyed blue for better visibility). This is easily achieved  by fixing  the 4 lengths of plastic tube to a plank  and  filling them with blue water and then adjusting their relative heights until all the levels are the same and then chopping off the tops at an equal height and bunging the open ends up to make an airtight seal using a suitable size screw with some silicone sealant . The gap between the top of the water and the sealed end forms a partial vacuum called the torricelli vacuum (google it) when you apply suction to the open end ( for example when you connect a running engine). Volume of the trapped air in all four tubes has to be the same for the water levels to respond identically to changes in vacuum from the engine.

Provided you calibrate them so that all the water levels are equal AND they all have the same volume of air trapped in the blind sealed end AND there is sufficient vacuum to prevent the suction from the engine drawing the water through into the combustion chambers, you will have four equally accurate manometers capable of balancing your carburettors very nicely.

I connected the open end of the plastic tube to the inlet pilot holes using 6mm brake nipples cut down so they didn't interfere with the air flow inside the air inlet stubs. As the engine warms up the plastic tube did tend to get a bit sticky but this just means you have to be quick or perhaps use a water spray to apply localised cooling. (I was just qucik).

When the engine is running the water levels jump about quite a lot but when you start adjusting the carburettors you can get a very good sense of the right level. I guess if you experimented further with the size of the vacuum and the length of tube and the amount of water, you could reduce the amount of bounce.

All for the price of of 30 m of 3mm or 4mm ID (can't remember) clear plastic tubing, four 6mm brake bleed nipples and a little effort.

I achieved my best ever carb balance with this method. Arguably more accurate than four pressure gauges.

[Bru-tom]

I made my own set of water manometers. THe tube length for the open ended type would be impractical for water, so i bunged up one end, taking care to ensure all four were bunged up with an equal level of water (dyed blue for better visibility). This is easily achieved  by fixing  the 4 lengths of plastic tube to a plank  and  filling them with blue water and then adjusting their relative heights until all the levels are the same and then chopping off the tops at an equal height and bunging the open ends up to make an airtight seal using a suitable size screw with some silicone sealant . The gap between the top of the water and the sealed end forms a partial vacuum called the torricelli vacuum (google it) when you apply suction to the open end ( for example when you connect a running engine). Volume of the trapped air in all four tubes has to be the same for the water levels to respond identically to changes in vacuum from the engine.

Provided you calibrate them so that all the water levels are equal AND they all have the same volume of air trapped in the blind sealed end AND there is sufficient vacuum to prevent the suction from the engine drawing the water through into the combustion chambers, you will have four equally accurate manometers capable of balancing your carburettors very nicely.

I connected the open end of the plastic tube to the inlet pilot holes using 6mm brake nipples cut down so they didn't interfere with the air flow inside the air inlet stubs. As the engine warms up the plastic tube did tend to get a bit sticky but this just means you have to be quick or perhaps use a water spray to apply localised cooling. (I was just qucik).

When the engine is running the water levels jump about quite a lot but when you start adjusting the carburettors you can get a very good sense of the right level. I guess if you experimented further with the size of the vacuum and the length of tube and the amount of water, you could reduce the amount of bounce.

All for the price of of 30 m of 3mm or 4mm ID (can't remember) clear plastic tubing, four 6mm brake bleed nipples and a little effort.

I achieved my best ever carb balance with this method. Arguably more accurate than four pressure gauges.

this is exactly how i built mine.

May i suggest using a higher viscosity fluid such as 2 stroke oil or atf. the water "bounces around" a lot less than water would in the tubes. Plus if any gets sucked up quickly due to a large imbalance, at least the 2 stroke oil is combustible unlike the water.

Also, i added vacuum restrictions in the pipes just before they meet the intake "nipples", this added an extra reduction in vacuum so as to not allow the levels to fluctuate so much. call it a buffer of sorts. i used small .22mm empty cartridges with 1mm holes i drilled into them, they are a nice tight squeeze into the pipes. you could use anything that will essentially block the end of the pipe that will allow you to drill through, and allow a "regulated" amount of air through at a time... This helped me out a lot and made the Manometer a lot more user friendly.

[awrawr]

Good idea. I will try oil next time I do this.

[ekpent]

 Morgan time    https://www.carbtune.com/

[DaveBarbier]

I hope you were careful with the spilled Hg. That stuff is highly toxic

Only toxic to vertebrates. Maybe invertebrates too...

[70CB750]

I got one of those somewhere too.   The sync tool I made from Surplus center manometers works well, but maybe the old Motion Pro deserves to be revived.

[carnivorous chicken]

Morgan time    https://www.carbtune.com/

I'll second this -- I left my mercury sync tool in Boston and picked up a Morgan.

[Deltarider]

Morgan time    https://www.carbtune.com/

I'll second this -- I left my mercury sync tool in Boston and picked up a Morgan.

Yeah, we know, we know but we admire much more the people that create something using their brain and hands. Although I share a professional EFKA synchronisation set (that I haven't used in years btw) I still like to build a DIY set and make it perfect, just for the fun of it. Beats buying.

[carnivorous chicken]

Yeah, we know, we know but we admire much more the people that create something using their brain and hands. Although I share a professional EFKA synchronisation set (that I haven't used in years btw) I still like to build a DIY set and make it perfect, just for the fun of it. Beats buying.

I have bikes in different places and one of the advantages of the morgan is its portability. But of course, to each his/her own.

[awrawr]

Morgan time    https://www.carbtune.com/

Don't know if they were available in 1988?

[pjlogue]

For the cost of Hg you could get a Morgan and have $ left over.

-P.

[PeWe]

I got mercury in my teeth until people started to think its toxic and forbid it.
What about a new synch tool? Like Morgan carbtune.