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daverbeck
02-03-2008, 12:29 AM
The left speedometer in my 94 Prosport 205 operates like the line is plugged occasionally. I was intending to disconnect the speedometer and blow out (at very low pressure) the line.

I noticed that both lines are connected to a cylinder that is about 0.5" X 10" located near the gas tank on either side. Is this a strainer to keep weeds and crud out of the speedometer?

If so I'll start there.

drbesvold1
02-03-2008, 12:36 AM
i blew my line out with a can of air spray and after i did that it worked perfect

rspiecha
02-03-2008, 06:04 AM
That long metal tube is like a vacuum tank for the speedo's. I think they call it a buffer tube. Helps make the needle on the guage move smoother up and down.

At one time, Team Mastercraft gave out a handy tool to its members. A pin looking object that would screw into the speedo pickup so you could pull out anything stuck in it.

Rob

TMCNo1
02-03-2008, 07:50 AM
That long metal tube is like a vacuum tank for the speedo's. I think they call it a buffer tube. Helps make the needle on the guage move smoother up and down.

At one time, Team Mastercraft gave out a handy tool to its members. A pin looking object that would screw into the speedo pickup so you could pull out anything stuck in it.

Rob

It's also called a balance tube among other things, just like the "H" tube on a dual exhaust system on a vehicle, it balances the pressure between the two tubes to keep them smooth.
Ah yea, the famous "Speedo Rooter" work like a drill bit to remove debris in the pitot pickup hole,
31256

learjet2230
02-03-2008, 08:56 AM
Ok, left hand speedo is dead. Cleared the pick up yesterday and nothing. I'll disconnect tub at speedo and pressurize the line and check again today. Is this "balance tube" common to both speedo's or one for each? Also, how often does the speedo itself go bad?

TMCNo1
02-03-2008, 09:00 AM
It is between the 2 tubes and works in conjunction with both speedos.

learjet2230
02-03-2008, 09:03 AM
Is there somethng in it that can fail, or is it pretty much a air/water filled tube?

TMCNo1
02-03-2008, 09:09 AM
Is there somethng in it that can fail, or is it pretty much a air/water filled tube?

Air filled, unless you have a air leak forward of the balance tube in a line or speedo diaphram and water has been forced into it and in the tube/tubes toward the leak, then it would have to be drained during winterization to keep the tubes and balance tube from freezing and bursting.

learjet2230
02-03-2008, 09:56 AM
Just found the problem (I think). LH speedo line was crushed under the gas tank. Got it out and tried to "open it" with a pair of pliers. Supposed to be 80 here today, so I will test it. If it doesn't work I will replace the line from the Pitot to the balance tube. Will keep ya posted. Thanks for the help.
Nik

ski_king
02-03-2008, 10:20 AM
It also helps if you change out the pitots.

Skidim has them.
http://skidim.com/prodinfo.asp?number=769B

learjet2230
02-03-2008, 10:56 AM
Well, back to square one. Just did a test run and nothing on the left side. Shouldn't need to change the pitots unless they are damaged, and the look ok. The boat will be going on the trailer in a week for some wiring work and I will track down the problem hopefully then.

mig
02-03-2008, 12:53 PM
I picked up one of these and it works very well. Made a little wedge to get the display onto the windshield where I wanted it. Never plugs up :)

http://cgi.ebay.com/G-top-HG-100-HUD-Bluetooth-GPS-Receiver_W0QQitemZ330188134545QQihZ014QQcategoryZ7 3332QQtcZphotoQQcmdZViewItem

east tx skier
02-03-2008, 02:07 PM
Well, back to square one. Just did a test run and nothing on the left side. Shouldn't need to change the pitots unless they are damaged, and the look ok. The boat will be going on the trailer in a week for some wiring work and I will track down the problem hopefully then.

The replacement pickups they have today are far less likely to clog than your OEM pickups. You'd need to drill new holes in the pickup to fit the pattern on your boat, but it's money well spent IMO. I run my boat in water with a fair amount of silt in it and I haven't clogged my replacement since I installed it whereas my stock pickup would tend to clog after only a few minutes of being in the water.

Damaged or not, I'd spend the $26 to not have to deal with them anymore.

jimmer2880
02-03-2008, 03:26 PM
The replacement pickups they have today are far less likely to clog than your OEM pickups. You'd need to drill new holes in the pickup to fit the pattern on your boat, but it's money well spent IMO. I run my boat in water with a fair amount of silt in it and I haven't clogged my replacement since I installed it whereas my stock pickup would tend to clog after only a few minutes of being in the water.

Damaged or not, I'd spend the $26 to not have to deal with them anymore.

I switched over last season to the new style also. They are great, but I've actually had more clogs than before. They seem to attract the grass much more. I had one that I had to bring a drill-bit down to get all the wood out.

But, I will say that they are much much easier to clean out than the old style.

I'm glad I switched.:)

TMCNo1
02-03-2008, 05:18 PM
I switched over last season to the new style also. They are great, but I've actually had more clogs than before. They seem to attract the grass much more. I had one that I had to bring a drill-bit down to get all the wood out.

But, I will say that they are much much easier to clean out than the old style.

I'm glad I switched.:)


It's Global Warming, I tell ya!:rolleyes: :D

Sitndux
05-21-2008, 10:23 AM
One of my balance tubes was stopped up so I bypassed it all together and the speedometer seems to work even better? Anyone ever tried this?

93 Prostar 190