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flat broke
06-08-2009, 02:07 AM
hey guy's last season the starboard pitot caught some debris and broke then at that time the speedo quit working. there is only one speedo in the dash the previous owner had removed one and installed a pp. I installed a new one today and had my gf spray a garden hose into it to confirm the repair nothing registered on the gauge thought that was weird ? so I told her to spray on the port side pitot the gauge moved ? so I removed the back seat and side and back covers and found on both sides these gold dumaflatchy things yes that was a very "technical" term so what are they ? and how does the boat register speed ? I would assume these gold dumaflatchy things convert water pressure into ? please help this not so smart guy thanks :D

WilliM1940
06-08-2009, 10:47 AM
I could be wrong but I think they are just tube sections used as accumulators to stabilize the pressure pulses from the pickup and settle the needle on the gauge. Love your avatar, always wanted a Sanger or Hallett on the mild side. There aren't too many back east.

JimN
06-08-2009, 11:15 AM
hey guy's last season the starboard pitot caught some debris and broke then at that time the speedo quit working. there is only one speedo in the dash the previous owner had removed one and installed a pp. I installed a new one today and had my gf spray a garden hose into it to confirm the repair nothing registered on the gauge thought that was weird ? so I told her to spray on the port side pitot the gauge moved ? so I removed the back seat and side and back covers and found on both sides these gold dumaflatchy things yes that was a very "technical" term so what are they ? and how does the boat register speed ? I would assume these gold dumaflatchy things convert water pressure into ? please help this not so smart guy thanks :D

The line from the speedo to the gold dumaflatchy things is supposed to be air, not water. The diaphragm in the speedo is very fragile and if water gets up to it, it will blow it out and leak all over the floor, etc. The gold dumaflatchy things and the pitot line is supposed to be sealed and if you have water coming into the bilge or wet carpet in one corner, it's often because of a cracked ballast (gold dumaflatchy things). Get access to the line to the speedo and blow air into it. A turkey baster or any kind of bulb will work, or you can blow into it yourself (I'm pretty sure your gf won't want to put her mouth on it). If it works, blow back toward the pitot and if it's not clear, you can find the cause by eliminating one part at a time- the ballast, line or the pitot itself.

flat broke
06-08-2009, 12:34 PM
thanks for all the tech info :) so if I find the ballast have a restriction and or are bad where would I purchase them and how much ?

flat broke
06-08-2009, 12:38 PM
I could be wrong but I think they are just tube sections used as accumulators to stabilize the pressure pulses from the pickup and settle the needle on the gauge. Love your avatar, always wanted a Sanger or Hallett on the mild side. There aren't too many back east.

Thanks for the comment but they are huge $ pits and a lot of time in labor messing with them all the time. I guess it would have to be something you love or your passion to want to deal with all that comes with it.

JimN
06-08-2009, 08:54 PM
thanks for all the tech info :) so if I find the ballast have a restriction and or are bad where would I purchase them and how much ?

If the end cap is soldered on, you could separate it, clear out the little tubes at the ends and clean it out, reinstalling the end cap when you're done. If you or someone you know has a propane torch, it'll be fine for this.

TX.X-30 fan
06-08-2009, 10:12 PM
The line from the speedo to the gold dumaflatchy things is supposed to be air, not water. The diaphragm in the speedo is very fragile and if water gets up to it, it will blow it out and leak all over the floor, etc. The gold dumaflatchy things and the pitot line is supposed to be sealed and if you have water coming into the bilge or wet carpet in one corner, it's often because of a cracked ballast (gold dumaflatchy things). Get access to the line to the speedo and blow air into it. A turkey baster or any kind of bulb will work, or you can blow into it yourself (I'm pretty sure your gf won't want to put her mouth on it). If it works, blow back toward the pitot and if it's not clear, you can find the cause by eliminating one part at a time- the ballast, line or the pitot itself.




Clever, funny and helpful. 8p

flat broke
06-09-2009, 12:16 AM
ok guys I did some testing on both sides today. ok so the starboard side ballast is connected directly to speedo #1 on the pp. The port side has like a vacuum tee three port side's total one side comes in from the ballast then splits off and goes again to the pp another port goes to I think goes up to the speedo gauge. so when I tested with water sprayed into the pitot on the starboard side water and air will come out of the ballast ? "I take it that is bad" ? the port side when I sprayed water into the pitot no water came out and that is the side that will register on the gauge. just to be clear I "BLEW" :D through all the lines to make and check for any restrictions witch did not find or feel there is one at this time. sorry this crap is so long but I just need to where to buy a new ballast ? and how much ? and if I am on the right path ? Thanks guys for any help :)

flat broke
06-09-2009, 11:05 PM
bump..................

JimN
06-10-2009, 01:17 AM
ok guys I did some testing on both sides today. ok so the starboard side ballast is connected directly to speedo #1 on the pp. The port side has like a vacuum tee three port side's total one side comes in from the ballast then splits off and goes again to the pp another port goes to I think goes up to the speedo gauge. so when I tested with water sprayed into the pitot on the starboard side water and air will come out of the ballast ? "I take it that is bad" ? the port side when I sprayed water into the pitot no water came out and that is the side that will register on the gauge. just to be clear I "BLEW" :D through all the lines to make and check for any restrictions witch did not find or feel there is one at this time. sorry this crap is so long but I just need to where to buy a new ballast ? and how much ? and if I am on the right path ? Thanks guys for any help :)

Just fix the one you have. It's almost free to do that and you won't have to wait. If you can't solder it yourself, take it to a radiator shop. That goes for leaking oil coolers, too.

deereman
06-10-2009, 01:51 AM
are those speedometer ballasts something that has to be winterized or do the just kinda drain themselves when you pull the boat out? (its my first year with an inboard)

JimN
06-10-2009, 02:13 AM
are those speedometer ballasts something that has to be winterized or do the just kinda drain themselves when you pull the boat out? (its my first year with an inboard)

They should be blown out from the front, using air. Doesn't matter what the source is, but low pressure is best. They usually crack because they weren't blown out and then the water freezes.

flat broke
06-10-2009, 02:51 AM
Just fix the one you have. It's almost free to do that and you won't have to wait. If you can't solder it yourself, take it to a radiator shop. That goes for leaking oil coolers, too.

hey jim thanks for your help and replys :) my ? is. The water and air is coming out the top part where it would feed to the signal to the gauge. The external housing does not show any sign of leaks "in one hole and out the other" so is there a internal diaphram that is poss leaking causing my problem ? and if so how would I repair the ballast ? thank you :)

flat broke
06-10-2009, 02:55 AM
They should be blown out from the front, using air. Doesn't matter what the source is, but low pressure is best. They usually crack because they weren't blown out and then the water freezes.

I live in northern cali it does not get to cold. It gets to the freezing point but my buddy never winterizes his boat and never has any problems. I do mine though just in case.

JimN
06-10-2009, 09:04 AM
hey jim thanks for your help and replys :) my ? is. The water and air is coming out the top part where it would feed to the signal to the gauge. The external housing does not show any sign of leaks "in one hole and out the other" so is there a internal diaphram that is poss leaking causing my problem ? and if so how would I repair the ballast ? thank you :)

It's a closed cylinder with a little stub on each end. The diaphragm in the gauge keeps water from shooting up to the gauge. If air and water are coming out at the top, it's either a crack in the ballast, a split in the thin tubing or a gap where the tubing fits onto the stub end. Those are your only choices. If the tuning and ballast are sealed and the gauge's diaphragm is intact, the water pressure from the pitot compresses the air, causing deflection of the gauge's needle. The ballast tempers the pressure changes in order to keep the mechanism from reacting too much and because it would react too slowly if the mechanism was made to be less sensitive.

Air and water coming out means it's leaking, whether you can see where the leak is, or not.

JimN
06-10-2009, 09:17 AM
I live in northern cali it does not get to cold. It gets to the freezing point but my buddy never winterizes his boat and never has any problems. I do mine though just in case.

A little bit of water in a small brass cylinder doesn't need to get as cold as a motor. Ice crystals start to form at about 39F when water's density is highest and brass is considered a "cold" metal, which conducts heat very well. The amount of time needed to freeze that amount of water at 32 is not much more than a few hours and water is one of the only substances that expands as it freezes. Once the water in the stub ends is frozen, the water will expand and burst the thin walls of the cylinder.

In December of '91, LA was in the upper 20s. The pipes in My cousin's house, which was in Menefee, froze and burst that night and that's a lot harder to do than split little ballast tubes. It took one night for them to freeze and burst.

flat broke
06-12-2009, 09:04 PM
It's a closed cylinder with a little stub on each end. The diaphragm in the gauge keeps water from shooting up to the gauge. If air and water are coming out at the top, it's either a crack in the ballast, a split in the thin tubing or a gap where the tubing fits onto the stub end. Those are your only choices. If the tuning and ballast are sealed and the gauge's diaphragm is intact, the water pressure from the pitot compresses the air, causing deflection of the gauge's needle. The ballast tempers the pressure changes in order to keep the mechanism from reacting too much and because it would react too slowly if the mechanism was made to be less sensitive.

Air and water coming out means it's leaking, whether you can see where the leak is, or not.


Those are your only choices. well if I apply water to the pitot and it is connected to the bottom of the ballast and I can put my finger over the top with no tube hooked up. of the end going to the gauge no water or air show sign of leaks until I remove my finger from the top and then water and air will come out the top. vs on the other side no water will come out the top when I do the same test ?