What is this doohickey?

duhmey

Seaman
Joined
Sep 18, 2011
Messages
69
Since working on my boat is out of the question (the boat is being stored an hour away and I am strapped for cash) I thought I would ask a question that has me befuddled:

What is this thing?
P9220227.JPG

P9220226.JPG

There is a cable attached to it that runs to the dash...is this for the speedometer? The only things on the dash are a speedometer, steering wheel and a switch or two (for lights?)
 

zopperman

Lieutenant Commander
Joined
Jun 22, 2011
Messages
1,551
Re: What is this doohickey?

what kind of boat..?
looks like an old spedo... vacuum tube should run to dash. should give you some resistence whne you move it.

ditch it and get a GPS... very inaccurate
 

cr2k

Captain
Joined
Mar 19, 2009
Messages
3,730
Re: What is this doohickey?

I didn't know any speedos worked on vacuum? Most work on pressure. If it has wires good question what it is. If it has a tube pinch while running and see if speedo quits. And BTW pitot speedos in good order are not that far off from gps.
 

QC

Supreme Mariner
Joined
Mar 22, 2005
Messages
22,783
Re: What is this doohickey?

For some reason no one has said the magic word although cr2k is on it . . . The doohickey is a Pitot :) And like cr2k I have had two VERY accurate ones. Within 2% of GPS, and remember a GPS is speed over the bottom, not over the water . . . and if you don't know why I mention think river ;)
 

duhmey

Seaman
Joined
Sep 18, 2011
Messages
69
Re: What is this doohickey?

Who'd have thunk it... Thanks guys! The boat is a 1969 Crestliner Mustang.
 

zopperman

Lieutenant Commander
Joined
Jun 22, 2011
Messages
1,551
Re: What is this doohickey?

Really? I've had nothing but bad experiences with speedos..
I have no idea why I said vacuum :eek: It was early and I needed my coffee..
 

H20Rat

Vice Admiral
Joined
Mar 8, 2009
Messages
5,204
Re: What is this doohickey?

For some reason no one has said the magic word although cr2k is on it . . . The doohickey is a Pitot :) And like cr2k I have had two VERY accurate ones. Within 2% of GPS, and remember a GPS is speed over the bottom, not over the water . . . and if you don't know why I mention think river ;)

which is why my pitot is MORE accurate than the gps.. :p
 

sschefer

Rear Admiral
Joined
Nov 13, 2008
Messages
4,530
Re: What is this doohickey?

It's mounted way to high to be a pitot style speedo pickup. My bet is it's a pickup for a live well. Oh, FYI GPS SOG is far more accurate than a pitot style speedo. Unless it's calibrated for the altitude it will never be accurate. GPS units that also have WAAS and a high sample rate are far more accurate at any altitude. The paddle wheel style sensors are the most accurate but they're really difficult to setup and only good to about 3mph, 5 mph is tops.
 

chriscraft254

Commander
Joined
Jun 4, 2011
Messages
2,445
Re: What is this doohickey?

For some reason no one has said the magic word although cr2k is on it . . . The doohickey is a Pitot :) And like cr2k I have had two VERY accurate ones. Within 2% of GPS, and remember a GPS is speed over the bottom, not over the water . . . and if you don't know why I mention think river ;)

QC, what exactly are you implying? I don't understand?
 

sschefer

Rear Admiral
Joined
Nov 13, 2008
Messages
4,530
Re: What is this doohickey?

that's a pitot.... needs to be flipped down tho

I thought about that but unless the angle is deciving it's still to short to work after the boat was on plane. I dunno, maybe the boat doesn't ever plane.
 

chriscraft254

Commander
Joined
Jun 4, 2011
Messages
2,445
Re: What is this doohickey?

I would be more concerned with all the cracked gel coating on the transom.:eek: Sorry had to point it out.
 

sschefer

Rear Admiral
Joined
Nov 13, 2008
Messages
4,530
Re: What is this doohickey?

[/B]
QC, what exactly are you implying? I don't understand?
In a river the pitot tube could be registering 2-3 mph or more with the boat standing still or vice versa if going downstream. GPS would always be correct since it is speed over ground not speed over the bottom.
 

chriscraft254

Commander
Joined
Jun 4, 2011
Messages
2,445
Re: What is this doohickey?

In a river the pitot tube could be registering 2-3 mph or more with the boat standing still or vice versa if going downstream. GPS would always be correct since it is speed over ground not speed over the bottom.

Ok, whew, thanks for clearing that up! I must have read what he wrote wrong. Because in my brain, it translated into the gps wasn't as accurate. I obviously haven't had enough to drink. Just kidding, I don't drink.
 

smokeonthewater

Fleet Admiral
Joined
Dec 3, 2009
Messages
9,838
Re: What is this doohickey?

I thought about that but unless the angle is deciving it's still to short to work after the boat was on plane. I dunno, maybe the boat doesn't ever plane.

I think the angle is deceiving... also it looks like it could be slid down in the bracket





BTW the point about the river is that often we want water speed.... GPS won't give that to us river boaters.... My plotter is set up for both gps and paddle wheel.... My paddle wheel sender is in my thru hull 'ducer and died a horrible death by trailer bunk before I built the guide-on's.... of course ... I don't have a whatcha-ma-doozie on the back to compare too. :(
 

oops!

Supreme Mariner
Joined
Oct 18, 2007
Messages
12,932
Re: What is this doohickey?

i cannot beleive..........we have so many experts on this thread......
i mean guys that really know there stuff........

And none of you has answered correctly.

Its a doohickey......geez guys......get it right !
 

duhmey

Seaman
Joined
Sep 18, 2011
Messages
69
Re: What is this doohickey?

that's a pitot.... needs to be flipped down tho

Ok, that explains the part on the bottom that flips up and down. (and there is mention that it may be an extendable one due to its current mounted height). Now that we know what this is, can you tell me how it works? When I am in the water do I flip down the bottom piece and I'm ready to go?

CC as for the cracks in the transom...I think I will have a chance to do a drill test today so I will study it with a close eye to check it out for sure and see what kind of shape it is in.
 

duhmey

Seaman
Joined
Sep 18, 2011
Messages
69
Re: What is this doohickey?

i cannot beleive..........we have so many experts on this thread......
I mean guys that really know there stuff........

and none of you has answered correctly.

its a doohickey......geez guys......get it right !

so i was right!? :)
 

sschefer

Rear Admiral
Joined
Nov 13, 2008
Messages
4,530
Re: What is this doohickey?

i cannot beleive..........we have so many experts on this thread......
i mean guys that really know there stuff........

And none of you has answered correctly.

Its a doohickey......geez guys......get it right !

We can always count on you for the correct answer ... ROFLOL... Actually..... I agree....LOL...
 
Top