How do you rig your shop tach for 1 man test

Rabbitdawghunter

Petty Officer 2nd Class
Joined
Jun 20, 2003
Messages
147
One of the first things that everybody advises when trying to prop a boat is to use a known good shop tach. The only kind I know of that would allow one person to see from the helm while operating is a tach with long leads like you would see on the instrument guages. Any ideas on the subject from the "Old Salts".
 

rodbolt

Supreme Mariner
Joined
Sep 1, 2003
Messages
20,066
Re: How do you rig your shop tach for 1 man test

hello<br />my "shop" tach is a ferret instruments digital inductive timing light. if I need to I can duct tape it someplace where its visible when I need it. what I havent figgured out is how to check timing at WOT on the water by myself. arms is to short :)
 

Clams Canino

Commander
Joined
Jan 10, 2004
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2,179
Re: How do you rig your shop tach for 1 man test

You don't need a shop tach to play prop scientist, just a "known good" tach. My boat has a Faria guage set. The tach is properly wired to one leg of the stator and set accordingly. It *works* is all.<br /><br />I'm more than happy setting up a prop by that tach. Your boat outta have a good tach anyway. Just hardwire a new one in and then begin the games.<br /><br />-W
 

rodbolt

Supreme Mariner
Joined
Sep 1, 2003
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20,066
Re: How do you rig your shop tach for 1 man test

I still check ll hull tachs against my shop tac. its amazing how far most are off at various RPM ranges.<br />some are correctable with the cal pot and others are just off. as long as I know how far and if its a constant it really may not matter. I send 1 out of every 5 or so new tachs back.
 

Dhadley

Supreme Mariner
Joined
Feb 4, 2001
Messages
16,978
Re: How do you rig your shop tach for 1 man test

We use the old OMC shop tach. Its digital, has an extension harness and in in a square box that sits nicely on just about any flat surface.<br /><br />On the race boats (and some hard to drive performance boats) we use a memory tach. Just in case youre a bit too busy to watch a tach at speed.
 

rodbolt

Supreme Mariner
Joined
Sep 1, 2003
Messages
20,066
Re: How do you rig your shop tach for 1 man test

Dhadley<br /> whadda ya mean "too busy".<br /> all us race bubbas can tell by ear a difference of 100 RPM and we can tell by the sound of the motor if its on the redline. same as setting the timing. all good mechanics can do it by ear and the great ones can set timing advance by ear. I know what ya mean though :) <br /> sometimes it do get a bit hectic. never raced boats but did 1/4 and 1/8th mile as well as some roundy round. some times when plan A&B both failed and your busy trying to remember plan C it does get a bit busy :)
 

Clams Canino

Commander
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Jan 10, 2004
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2,179
Re: How do you rig your shop tach for 1 man test

Ya, I *know* what an inline sounds like at 4100-4200 by ear. And kinda "compensate" for strange tach behavior based on the 4200 mark. Funny, I had to send my 1st Faria tach back for another one, I thought it was an anomaly... one in 5 makes me wonder if it was now.<br /><br />-W
 

rodbolt

Supreme Mariner
Joined
Sep 1, 2003
Messages
20,066
Re: How do you rig your shop tach for 1 man test

clams<br /> my opinion of Faria,whether it was branded as system check or Faria, is rather low. had a lot of problems with tach failures with them.
 
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