Gauges are going CRAZY, please help!!!

Long story, please bear with me as i need your help

There has only been 1 problem with the 1995 Chris Craft Concept 18 i bought a few weeks ago and that was that the stereoonly worked out of one speaker and you had to push in on the faceplate to get it to do that. I noticed that at top spped water would splash onto my leg under the dash and it felt like it was coming out of the stereo, so stupid me thought it was waterlogged.

Tonight I decided to figure out what was really going on and i wish i never did. Good news is that i found where the water was coming from and i fixed it. It was coming from the tube connected to the back of the speedometer and by attaching it as far up the nipple as it would go everything was sealed and no more water. However in doing that (and i got nothing else wet or loose I am sure of it) but in doing that now most of the other guages are F'ed/ Here is the deal

Before the oil pressure guage worked perfectly, now it reads the same as before when in neutral and idling but under load it pegs out at the max level and stays there

Before the horn button worked fine and the horn blew hard. Now no horn noise and when you push the button it makes all of the lower guages peg out (oil temp, coolant temp, gas, voltage)

Before the voltage gauge would sit right at 14 where it should. Now it jitter around at 11 or 12 and is erratic

Before the trim guage worked perfect and the boat would trim out right about 40% up the scale. Now when the lower unit is all the way down the trim guage is laying on the bottom dead and when i know i have the engine trimmed out for top speed (I can tell by performance and sound and feel) it is only 1/4 way up

Before i had just filled the gas tank tonight at the marina and when it was full (before all of these problems) it looked ont he guage to be about 7/8th full. Now it is pegged full. Maybe this is ok, i dont know as this is the first time i have filled her up but who knows

I am really distraught over all of this. I went thru every guage on the bottom of the dash tonight, they are all dry, all have tight connections, all wiring harnesses look and feel new and tight. I do not know what to do

Please advise, i do not want to get taken to the cleaners for repairs as i am sure something stupid has happened that must be a simple fix, it is not like one guage went bad. The whole things i acting nuts and as you can see from the above all in different ways, some dont work (horn), some are erratic)Voltage), some are wrong (trim) etc

HELP ME PLEASE!!!!!!!!!!!!!!

Re: Gauges are going CRAZY, please help!!!

Look for a broken/loose ground wire that is common to all the gauges.

Re: Gauges are going CRAZY, please help!!!

I looked all over down there and everything looks tight and perfect and in new condition.

How can this be this issue though, if you look at the trim guage it still triggers and start to "go up" but it happens much later int he trimming process and is off calibration. Wouldnt a ground issue either be there or not. I can understand that causing jumpy readings etc but if you look at the trim for instance it works smoothly but is just way off.

Also with the oil pressure guage, it reads normal at idle and then is just pegged high when under any load, the horn makes all of the jump to the max spot, etc, they are not just jumping around and are all acting different

I am really ticked about this, i know i am going to be spending a fortune at the marina over something stupid, i have gone thru all of the cabling I can see with a fine toothe comb and everything looks perfect.


Please let me know any further detail that may help, this is driving me NUTS

Thanks,
Robert

Where would i look exactly for this grounding issue.

Re: Gauges are going CRAZY, please help!!!

Get a length of wire long enough to reach the battery from the dash. Touch one end to the ground terminal on ANY gauge. Have a buddy touch the other end to the NEGATIVE (I SAID NEGATIVE - NOT POSITIVE) terminal of the battery. If the gauges and accessories come to life, you have a ground issue as was pointed out above. Since you mucked with things in the vicinity of the speedometer, look for a ground connection that you accidentally mucked with when you mucked with the speedometer. The cause of lights or electrical items that act weird is almost always a bad ground connection.

Re: Gauges are going CRAZY, please help!!!

Just because the wiring LOOKS good doesn't mean the current can flow freely. You might have to take each wire connector off, then clean it and the terminal. Do them one at a time until you're back in business.

Re: Gauges are going CRAZY, please help!!!

Waht about the 3-4 harnesses down there. Any chance they are the culprit.

This is really eating me up. I cannot understand the trim one in particular. I could understand a ground being loose causing jumpy readings or something not to work but why would the trim guage still"work" but be WAY off on calibration

Also why would pushing the horn button cause all of the guage to peg out.

Any chance the battery has something to do with this. The first battery i put in when it was new had a bad cell. They put in a new marine battery and new battery cables and until my gauges went nuts yesterday it would sit right at 14 on the voltage gauge on the dash. Now it is a little jittery around 11. Also like i mentioned the oil pressure gauge works fine until i give it some throttle and then it just pegs out.

I know i am a broken record but i do not see anything down there out of whack. I spent hours tightening, etc. Everything was already tight and i cannot find anything wrong. Also the tach and speedo work fine.

I am really confused and frustrated??

Re: Gauges are going CRAZY, please help!!!

You have a choice here. 1) Get down, get under, be logical, and take the advice that's given in an attempt to fix the problem yourself, or 2) Take it to a shop. Continuing to harp about the issue does not get it fixed. A bad ground causes electricity to do whatever is necessry to get back to the negative terminal of the battery. In the process the circuit can, as you are seeing, go goofy.

Re: Gauges are going CRAZY, please help!!!

Robertpel9 said:

Good news is that i found where the water was coming from and i fixed it. It was coming from the tube connected to the back of the speedometer and by attaching it as far up the nipple as it would go everything was sealed and no more water. However in doing that (and i got nothing else wet or !!

Click to expand...

Why is water coming out your speedo tube it shouldn't be that way. Don't they just work off suction. The little white thing on the back of the boat moves up as the boat goes faster sucking the needle on the gauge around the dial.

Check it out and see if it's the problem cause it all started when you hook water i.e. the water your boat is running in to your gauges.

Re: Gauges are going CRAZY, please help!!!

How do i find the common ground wire, does it run all the way back to the battery.

There are A LOT of wires under there, trying to narrow my search

Re: Gauges are going CRAZY, please help!!!

NSBCraig said:

Why is water coming out your speedo tube it shouldn't be that way.

Click to expand...

That is how they work..they work on pressure.

Re: Gauges are going CRAZY, please help!!!

Robertpel9 said:

How do i find the common ground wire, does it run all the way back to the battery.

There are A LOT of wires under there, trying to narrow my search

Click to expand...

Look at the back of the guages. There will be one wire that has a common color on all the guages. More than likely it will be black but could be another dark color. That will be your ground. It should eventually connect up to a ground bus near the fuse block.

Re: Gauges are going CRAZY, please help!!!

I am not near the boat now as i am at work but i think there is an orange wire on each guage. Also i think coming off the horn there are two orange wires one has a white line in it and one does not, does this make sense?

Re: Gauges are going CRAZY, please help!!!

any chance this is a water issue as the speedo tube did drip water onto the wire bundle which may have dripped into a harness, how would i go about correcting that??

Re: Gauges are going CRAZY, please help!!!

Robertpel9 said:

I am not near the boat now as i am at work but i think there is an orange wire on each guage. Also i think coming off the horn there are two orange wires one has a white line in it and one does not, does this make sense?

Click to expand...

Orange should be hot look for black.

Re: Gauges are going CRAZY, please help!!!

Boat manufacturers are all different so it could be any color. There will normally be 3 wires common to all the gauges, ground, power and back light.

Since your horn is causing a voltage drop, it is more likely the ground connection up at the ground bus near the fuse block or the ground connection near the engine at the end of that same wire.

Re: Gauges are going CRAZY, please help!!!

Really who doesn't use black for ground?

Re: Gauges are going CRAZY, please help!!!

OK got home tonight and went to work armed with your info

i first disconnected the horn to take it out of the picture, no difference.

Then i went through every damn wire connection back there and unplugged all harnesses, ensured they were clean and dry and reconnected everything - No difference.

I went back to the fuse panel and ensured everything was connected, no difference.

I then went back to the battery, the cables were pretty tight but i could move the negative cable arounf if i pushed on it so i took everything off the negative post, ensured it was clean and dry and then tightened it down very tight, no difference

I then just went to tighen the positive post cabl on the battery and it was already tight and the POS clamp broke, I will need a new one but this was not the issue anyway

Here is the state of the guages

Tach - perfect (Always has been)

Speedo - Perfect and not leaking anymore

Oil pressure - sits at about 55 when idling, with any engine RPM increase it pegs out to the max reading (80)

Coolant - I think this one is actually working propery although it seems to be reading higher than it used to, at least it is not all over the place

Voltage - Sits pretty steady at 12 jitters a little bit - it used to be solid at 14 when the engine was running (Could all of this be an alternator problem?)

Gas - Pegged at full - i did just put $120 in gas in last night so it may very well be full but i floored it for over 20 minutes tonight and it never dropped at all

Tile - Still off calibration from what it used to be - see top of post

Horn - reconnected after testing all of the above and still not functional.
When you push the button it makes half of the guages peg left and half of them peg right


I am at a loss, i do not want to pay a marina to fix something simple but what else can i possibly do. Please let me know if any of the above is helpful and if anyone has any further ideas. The boat runs perfect but this is driving me nuts. I do not feel ccomfortable useing the boat without a oil pressure or fuel guage

Thanks,
Robert

Re: Gauges are going CRAZY, please help!!!

Did you find the ground bus near the fuse panel? When you fianlly find it, measure the drop between it and the negative post of the battery when you blow the horn. You will need to make a long lead to reach from the meter all the way back to the battery. This will determine the voltage drop in your ground cable. After you do this, do the same for +12V. Measure from the positive point on the fuse panel all the way back to the positive terminal of the battery when you blow the horn.

Re: Gauges are going CRAZY, please help!!!

Take one of the suspect gauges and ground it as suggested above and see if the issue goes away, maybe your oil pressure to start with. You can also put a volt meter across the battery and check to see if your volts gauge is actually reading correct or you have multiple issues with various systems. Not likley though.

I have had a bad ground on older boats that did all kinds of weird things that you would never think about.

Oh, and I hope you didn't gun it while on muffs....

Re: Gauges are going CRAZY, please help!!!

bhammer said:

Oh, and I hope you didn't gun it while on muffs....

Click to expand...

I am a little confused. I am a true beginner when it comes to electrical. What am i looking for when i test these drops in voltage?

Is it possible this is related to the alternator in any way, can i be getting fluctuations in voltage

I am not sure what to look for when i do these tests

what did you mean by gun it when on muffs?? Do you mean when it is out of the water?? It is in a dockslip at my subdivision dock area, I am working on it while it is in the water, if that means something else please let me know

I am really lost here, i am sure all of the wires at the fuse panel are connected well and are dry and intact, i do not know what to do.

I know i am being a PITA but please be more specific

Thanks,
Robert