R-Don

I have spent the last two days trying to sort out a voltage leak on my formula which is draining the batteries.

At the end of last season i noticed that the fog horn was not working and the dashboard voltmeter would drop significantly when the horn button was pressed.

Upon checking the horn circuit:

The air horn pump motor is OK.
I have 12V at the horn isolator switch.
I have 12V at the other side of the isolator switch when it is on.
I have 12V going into the horn switch.
And i have 12V arriving at the horn pump when the horn button is operated.

This leads me to conclude that the problem is either:

Poor earth connection or dodgy horn button.

Firstly i connected a voltmeter to both sides of the horn button and took a reading when the button was operated, this read 8.5V !! This does not seem right to me.

Next i traced the earth wire from the horn pump back into the rear of the Dash Panel. Here i found about 5 large block connectors all held closed by cable ties. Upon closer inspection the connections seem to be dry (a white powdery coating on them), Should these not be protected with something?

Also, a number of wires appear to be cut where they exit the block connectors!!

The boat is Factory Standard with the only additional fitment being Bennet Trim Tabs. So i am not sure why the wiring appears to be tampered with.

A further fault appeared today, when the stereo is on, if you crank it up the player shuts down and re starts then shuts down again and so on until you reduce the volume and then it appears to be OK. Does this sound like an earth problem as well?

Hope this makes sense and i would welcome all advice as usual as im aiming to be in the water in the next two weeks.

Thanks.

CObarry

Electrical problems can be a pain in the @ss...

Based on the stereo shutting down it sounds like you could have a voltage drop issue somewhere. If the unit detects low voltage it will turn itself off or just shut down from lack of voltage. Turning up the volume is going to draw more current, which will cause the voltage drop if the wires/connections can't carry the current. I'd go down the path of verifying your grounds are good first, and I'd measure the voltage at your stereo as you increase the volume.

If you've got a draw somewhere the only way I know to find it is to monitor the current draw at the battery, and start unplugging/disconnecting stuff until you find the culprit. Tough to diagnose over the Internet, hope this helps...

R-Don

Thanks CObarry.

Would the stereo shut down due to a low voltage in and/ or because of a bad earth from the set?

Whats the best way to clean up the block connections and is their something i can spray onto them to protect them from corrosion in the future?

Thanks.

CObarry

It could shut down for either reason.

I'm not sure how bad the terminal block is from your description, but the brute force method would be to cut the terminals (probably ring lugs) off and re-crimp new ones on the wires, as well as replacing the terminal block itself. Before I went to that extreme I'd remove wires one screw at a time and clean everything up then retighten the screws. Have you checked all fasteners for tightness? Age & vibration have a way of working things loose...

R-Don

The common earth block contains 5 or 6 male to female bullet connections housed in a clear rubber type block which seperates into two halves. (With me?).

When seperated, the terminals are dry but with a sort of fine white powder coating on them. This could either be corrosion or the residue of some kind of protection film applied at the factory.

Poorsche

For the Corrosion (white powdery stuff) get some stuff called CorrosionX--the have a website.

I had a similar problem not long ago and it turned out that there was corrosion (Green stuff in my situation) on the connectors in the plug that connected the engine wiring harness to the harness that ran to the dahsboard panel. I opened up that large, round connector at the engine and gave male and female portions a good "douche" with CcorrosionX and poof--no more of that problem.

Good luck--

Audiofn

First I assume you have had your batteries tested? How well do the motors turn over? IF they turn over well then your ground at the engine is probably ok. If they turn over slow then you may have bad cables or connections. As has been said it is almost impossible to diagnose over the net. Wires can look good but be corroded inside or at the ends. If they are corroded they need to be replaced. You can clean a lot of corrosion off with simple backing soda mixed with water deal and a tooth brush. You can also use scotch bright pads to get the real nasty stuff.

Once you find the problem and you want to protect stuff use Mercury Corrosion guard. It works very well to keep things looking nice.

Jon

R-Don

Poorsche,

Thanks buddy. I too have green stuff, its not on the end of the connectors, but it can be seen through the clear rubber block connectors.

Audiofn,

Thanks for the advice.

I am off to the boat yard now with pen, notepad, test light & multi meter. I intend to work through a systematic approach and test the hell out of everything in sight.

Ill let you guys know how i get on later.

Thanks.

ThirdBird

One thing that caught my attention here is that you said "air horn". Did you really mean an actual air horn? As far as I know, Formula did not use air horns as origninal equipment, at least not on a 242. The original horns are dinky little electric things.

The point of this is that if the horn was added later and you're seeing voltage problems/corrosion at those connenctions, then whoever installed it didn't do it very well. Formula heat shrinks every lug on every wire. Maybe you should just disconnect that "fog horn" and see how that works out.

5PMSMWHR

Third,

I beg to differ with you on this one, but..... The "fog horn" was a 242 option on models sold in the coastal new england and pacific northwest.