Electrical issues

"Hi guys, I am new to this boa

"Hi guys, I am new to this board and new to boating.
I recently bought my first boat, a 1987 17' VIP bowrider, it has a OMC Cobra I/O with a 120hp Ford 2.3L engine.

It hasn't been run since 2006, I have got it cleaned up and have changed the filters, plugs, points, impeller etc, using muffs I have started the engine and was really surprised how easily it started, just a few cranks and away it went, no problems at all.

The problem I do have is electrical, I think?
The Tachometer doesn't work... taking readings from the back of the Tach, I have a good 12v on the live and ground... 12v ground to sensor terminal and variable voltage live to sensor terminal ( changes with rpm ).

Also my Tilt and Trim gauge doesn't work, it moves slightly when the key is turned on, but no further movement as the tilt is operated.

Also voltmeter on console shows close to 18v at just above idle speed, I haven't checked voltage across the battery with the engine running, the battery is fully charged and when I bought the boat the previous owner said the battery is new!!!

I am wondering if the alternator is bad and whether that would cause all three problems?

I was hoping to get out and check the voltage across the battery this weekend, but here in Missouri and typically if ya wanna do something outside this time of year, we have rain and thunderstorms...

Any help you guys can give would be most appreciated.

Barry"

"What kind of alternator is it

"What kind of alternator is it? If it is a Motorola, look to see if it is grounded to the negative battery terminal."

"Not sure Kevin, its been too

"Not sure Kevin, its been too wet here for me to uncover it, there is a separate black wire that goes to a small terminal with a wingnut on the battery, would that be it ?
I've always connected it when running the motor, but not if i've just been working on the boat and only connected the battery for the radio... I'll check this out at the weekend, but I have a feeling that with the engine NOT running, the boats volt meter shows 12v with that little black wire connected, but only 8v with it disconnected, with a fully charged battery ???

I look forward to any help you can offer.

Barry"

Sorry Lewis Leonard... I have

Sorry Lewis Leonard... I have no idea where the name Kevin came from ???

"That wire is probably the tri

"That wire is probably the trim pump ground. And no, it will not cause your problems. The gages are 21 years old and most likely spent. You should have AC voltage at the gray tach lead while the engine is running. If you do and the (+) and (-) are all good, the tach is junk. Regarding the trim ga, look to see that the trim sender is moving properly and has not been knocked off. You can also ohm is to see if it is good.

I hope this has been helpful.

rick"

"Thanks Rick, looks like it&#3

"Thanks Rick, looks like it'll be the weekend before our weather will be dry enough to uncover the boat, i'll check the trim sender then.
If the tach is shot will a regular automotive one be ok to use ?

Barry"

"overtons" has a complete

"overtons" has a complete 6 gauge white face set( marine grade btw ) for 159 and they look sharp!"

"Thanks Kevin,
I took a look

"Thanks Kevin,
I took a look at the gauges at Overtons, they look real cool, not sure I wanna dish out $160 bucks right now, but a single gauge at $59 sounds reasonable. Once I get this boat in the water and everything checks out ok, I might overhaul the console.

Today the weather has been reasonable and I got off work early, so did a little investigating on the charging system...
Rick, the black wire from the battery looks, as near as I can tell, cos it goes through a harness is to the fuel sender, the trim sensor is in place and operating it manually had no effect on the trim gauge

I connected my DVM across the battery and have 12v stationary... with the engine running it shows 14.5v most of the time, although at times it flickered around 17v - 18v, do ya think the regulator pack is going out ?

The Alternator is a Motorola, no direct ground wire to the battery, all connections look clean and are tight, there is a terminal with a wire connected to it thats marked AC ( something ) don't remember the color of the wire on it now, but would that feed the tach ?

Thanks for ya thoughts

Barry"

"Unless someone rewired it, th

"Unless someone rewired it, the trim sender does not ground directly to the battery, it grounds through the engine harness.

Regarding the tachometer, unlike diesels and outboards, your tach signal comes from the ignition system, not the charging system. Test the gray lead on the back of the tach for voltage with the engine running. If you have no voltage, then start chasing wires.

I would highly recommend purchasing the proper service manual for your engine and drive assy. It will contain wiring schematics, troubleshooting guides and some other very useful information. Being new to boating, there is no better way to familiarize yourself with all the systems which could potentially fail and leave you stranded somewhere. Typically, when you need this website the most, you're floating down the river and your wife is freaking out. The more you learn about your boat, the better, and safer, your boating experience will be.

Regards
Rick

http://http://www.marineengine.com/manuals/seloc/omc.html"

"This pic might help, sorry fo

"This pic might help, sorry for the quality. You can see 2 gray wires coming off the neg post of the coil, 1 goes to your ESA module (it grounds out the coil) the other one goes through the big black cannon connector up to the dash to feed your tach. I would pull the cannon connector apart and make sure it's clean and tight. You can see the trim sender on the far left, it comes through the transom and you will see 2 black wires going into a connector at the rear of the engine, you can pull that apart and check the resistance of the sender, the sender is the most common failure as it's under the water all the time when the boat is in the water.

"

"Thanks for the schematic Rick

"Thanks for the schematic Rick, I should be able to check some of that out at the weekend.
Regarding the wiring to the Tach, the grey wire from the Tach is connected to the coil, there is a voltage from that, that varies with the rpm. Does that indicate the gauge is probably F..... ( trashed ) ?
I am hoping to borrow a Tach to try on it.

The trim sender has two wires to it, would I be right i thinking one is power and the other sends the reading to the gauge ? there is a wire from the outdrive to the transom mounting that is hanging on by a thread, I am assuming this is a ground. I will check out the readings from the trim sender at the weekend, I assume the resistance from the two wires would change as I move the lever ?
I really appreciate the help you guys are giving me... Being new to boating and marine wiring etc, it is extremely helpful.

I guess one good thing from this not being a perfect boat when I bought it, is that I am going to be a lot more knowledgeable about the boat than I would have been otherwise.

Thanks guys

Barry"

"Actually, the name's Bob

"Actually, the name's Bob not Rick but I've been called worse (sorry Rick!) It does sound like your tach is nfg but another will prove that out. The trim sender just passes ground through it (variable resistor) and up to the gauge. Disconnect it behind the engine and use an ohm meter to measure, it's supposed to be something 10 ohms at one end 180 (I think) at the other end."

"Sorry Bob, I seem to be havin

"Sorry Bob, I seem to be having trouble with names on the board

The guy I was hoping to borrow a tach from couldn't help, so I bought a cheap automotive ($30) one today, i'll use that to check out with, if it works I think I will probably just go ahead and install it, I know it says "not for marine use" but i'm guessing that cos its not gonna last long in the damp conditions??? but I figure it'll do for now, at a later date i'll probably redo the whole console and fit all new gauges anyway.

I assume with the trim sender, I connect my Digi-tester on ohms across the wires from the sender and see if I get a variable reading from them as I move the trim sender arm ?... If that checks out ok, I do the same thing at the gauge end ?... and if that checks ok, I go get a new trim gauge... right ?

Thanks for ya help guys

Barry"

"I hooked up the new tach yest

"I hooked up the new tach yesterday and it worked fine, so you were right Bob it was the gauge.

I tested the trim sender and its shot, so I'll get a new one the next time I'm out at the marine shop, is it as hard as it looks to get that wire through the transom ? if it is, I think I'll splice the new one into the existing wire, solder and heat shrink tube the joints, then silicone and more heat shrink over that.

Got that done just after lunch, so decided to take a look at the trailer bearings, glad I did, the first wheel I looked at had 1/8" play in it, took off the bearing buddy and it looked like it has been years since it saw any new grease. The outer bearing came out fine, the inner bearing just fell apart, so I went out and got new bearings and seals for both wheels, got the first back together. I didn't have time to do the other wheel as we were going out to eat, at sons expense, so didn't wanna miss that... lol However it doesn't have the play the other wheel had, but feels a little rough, so I'll change the bearings in that one just for peace of mind. btw the trailer is a ShoreLand'r.

Thanks again for all ya help guys, you've been a great help.

Barry"

"Hey Barry...glad you got the

"Hey Barry...glad you got the tach working. Yes the trim sender wires are a bit of a pain. You can try the splice method but not sure how long that will last you, if the boat is on the trailer most of the time then it might be ok. There is a rubber tapered grommet with ridges on it that seals the transom hole. You need to go inside behind the engine, undo the 2 wire connector and actually remove the wires from it as it won't fit through the hole. There may also be a metal clip on the inside of the grommet to hold it in that you have to remove. Once you get the new one you'll see what I mean, it's a pain but can be done with a little patience and sometimes a lot of beer and cussing! "

In addition to Bob's comme

In addition to Bob's comment: add a piece of string to the cables before pulling them out. Makes it a bit easier to get the new one in. 'Lubricate' the rubber seal/grommet with Sealing Compound when pulling it back in.

"Hey guys, thanks for the inpu

"Hey guys, thanks for the input, I'll try doing what you suggest, I'll take a look at it and see if I can pull the wires through, if not then I'll revert to plan " A "...
Your advice and help is really great...
Thanks a lot

Hoping to get this on the water soon

Barry

PS... Anyone know the best type of tube to buy ?
I like to have a bit of adventure, but still be safe and fun for the rest of the family.
Been thinking about a safe 2 man tube for the family and something a bit more daring as a 1 man tube, are there any compromises??"

"From experience, never ride d

"From experience, never ride double tubes without some sort of helmet/head protection. The most common accident is they bang their heads together!"

"Morten...I hope that's no

"Morten...I hope that's not PERSONAL experience

Barry...not sure how old your little ones are but years ago when my 2 sons were tubing I bought this quick release from Sevlor (I'm sure they still sell them), it had a small cord from the quick disconnect with a rubber band that went around the wrist, if they got dumped the cord pulled the quick disconnect so the tube ended up being very close to them so they could climb back on rather than wait for the boat to bring it back around. Also if they got scared they could pull it on their own and they would be just sitting in the tube waiting for us to come back around and pick them up."

"Not closer than calling for a

"Not closer than calling for ambulance to get kids to hospital with concussion a couple of times. (Not mine!)
I simply refused even to sell tubes at my marina having seen too many accidents or close to accidents.
However correctly used it might probably be big fun.
Have mainly done, at least tried to, do my 'suicidal' activities with risk of only hurting myself."

"Hey guys I really appreciate

"Hey guys I really appreciate the warnings about tubing, really hadn't thought about that safety aspect of it. But, "the kids" are 24, but I might just get some safety helmets for extra peace of mind. I've been tubing myself and had a blast, even when the boat driver was hell bent on dunking me"