Checking al. hull for "proper grounding"

Luna Sea

Lieutenant Junior Grade
Joined
May 20, 2002
Messages
1,069
I was just reading a thread on here about stainless screws and aluminum hulls. Last response from FlyBoyMark was regarding shorepower and "properly grounded hulls" I have a digital meter but only use it to check voltage. Is there a milliamp or ohms (I'm not an electrician) setting I could put the meter on to check for stray current/bad grounds? Heading out to the mooring in 2 weeks! :) And worried about more pitting, have good zincs but......
 

crab bait

Captain
Joined
Feb 5, 2002
Messages
3,831
Re: Checking al. hull for "proper grounding"

no.. there's no way to measure that i no of..<br /><br />your multimeter has milliamp.. but you'll get a milliamp readin' on everthing metal.. <br /><br />touch it to the hood car,,anythin' ,, you'll get a readin'...<br /><br />just make sure you've got good tite uncorroded connections... <br /><br />thats as good as it gets...
 

FlyBoyMark

Ensign
Joined
Apr 14, 2002
Messages
934
Re: Checking al. hull for "proper grounding"

There is a way to measure and I just can't remember how to do it...it was on Ship Shape TV on a segment about zinc anodes and cathodes. Go to the Ship Shape TV site and email John Greviskies and ask him and he will email you back with the info. He really responds!!<br /> web page
 

Luna Sea

Lieutenant Junior Grade
Joined
May 20, 2002
Messages
1,069
Re: Checking al. hull for "proper grounding"

Thanks FlyBoy,<br />I'll do that. and if I get a good answer I'll post it on this site. Happy fishing! :D :D
 
D

DJ

Guest
Re: Checking al. hull for "proper grounding"

Luna Sea,<br /><br />You can do it, just like you check an automobile cooling system for current.<br /><br />Touch one lead to the negative battery post and the other to the water. The only way current (voltage) will show up is if there is something leaking current in the boat. It (current) would use the water as a medium to close the loop.<br /><br />You should look for voltage.
 

Luna Sea

Lieutenant Junior Grade
Joined
May 20, 2002
Messages
1,069
Re: Checking al. hull for "proper grounding"

Thanks djohns,<br /><br />Just taking all precautions/measures necessary to make sure I don't get any pitting in the al. again this year. Added zincs to boat, covered battery, ect. but have beeen warned of "stray" current. Could be a hidden wire for running lights or bilge pump that I can't see with a break or something. When I'm in da salt again I'll put the meter to it. Thanks and happy boating. YES it's almost here........ :D
 

karlp

Seaman Apprentice
Joined
Feb 11, 2003
Messages
31
Re: Checking al. hull for "proper grounding"

Luna Sea<br /><br />Read the replys with interest as I also have an aluminum boat in salt water. I asume that what is meant by grounding is that there should be no connection between the negative post of the battery and the aluminum hull as in cars where the chassis is sometimes used as ground to complete the circuit. Why can't a simple measuremnt of resistance (ohms) be made between the negative battery terminal and the hull with all electrical items operating ?
 
D

DJ

Guest
Re: Checking al. hull for "proper grounding"

Karl,<br /><br />That is correct. The entire electrical system must be isolated from the hull.
 

FlyBoyMark

Ensign
Joined
Apr 14, 2002
Messages
934
Re: Checking al. hull for "proper grounding"

Thats tuff to do...the engine on most all outboards are grounded to the crank case Which in turn is connected to the boat........
 
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