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help I shorted out my Honda Bf90

J

jakepitsville

Member
As above I stuffed up and I shorted out my positive starter cable to the side of my outboard - while I was trying to trim up the outboard, everything just went dead. Currently I have no tilt up/down and when I try and turn the engine over all I get is a load "CLICK". SO far I have found a blown fuse that I have replaced, but that didn't change any of the problems. I have removed the solenoid wire from the starter and tested the starter which works fine - when I turn the key with the solenoid wire disconnected from the starter I get the same load "click". I have gone through everything I can think of, searched for ages, studied diagrams etc and I am completely at a loss to what I have broken. Can anyone please help?? REally Really stuck. Regards Jake
 
First of all....is your engine carbureted or fuel injected? The wiring is different in each.

Explain a little more on what you shorted. Did you have the cables loose? Shorted it while jumping to something with a screwdriver? What exactly touched what?

Mike
 
Thanks for the quick reply hondadude. I was in the process of removing the engine after finding the appearance of an oil leak at the bottom of my fly wheel. I had disconnected and removed almost everything before realised I had jumped the gun as I had not pulled off the lower gear case. Most of the electrics were disconnected and the outboard was trimmed down so I connected trim back up and put the battery on, and started to tilt the engine up then it just stopped and I could hear something shorting - I didn't know where it was coming from so pulled the battery off.. I found that I had completly forgot about the main power wire from the battery to the starter and that was what was shorting out against the outside of the engine case I believe. The trim motor works as I have connected power directly to it and the starter works. but I am not sure whats not working inbetween to give me dead switches and just clunk when I turn the key.
 
ok again thanks Mike for such quick posts. so an update on my progress so far. yes its a carbureted model I believe the year of manufacture is 98 or 99. I managed to sort out that the trim motor works when power is supplied to it - power is also going to the trim relay box but power is definitely not leaving the relay box when I operate the trim/tilt switches either on the remote or on the side of the outboard, so my guess is most likely a blown relay box unless there is some fuse or ruined wiring with the switches - so far I have not worked out how to test if they are working. Still at a loss to why I cant get the engine to crank over via the key - is it possible to burn out the magnetic switch>? how do I test this or have I damaged something else??????
 
How did you get the starter to crank? Did you just jumper from the post on the starter or did you run a different wire?

I know more questions than answers at this point, but since I can not see what you are doing, you have to be my eyes.

Generally, if the positive cable was only shorted to the frame of the engine, I would suggest bypassing your battery switch and examining the main power cables from the battery very closely. If you have a battery switch in the circuit, that would be the weakest link and one of the areas to cause a voltage drop.


Mike
 
Good....that is a pretty good indication that the cables and battery connections are ok. It is stll a good idea to make sure the battery connections are clean and tight.

Ok....more questions.....rereading your posts, I interpret it as...you just pulled your powerhead to check the flywheel area. If so, you may have removed some small ground wires that you did not reattach or got cut in the process. But for now start tracing what works back to the key switch.

First...make sure your 30 amp fuse is good and you get power at each side of the fuse. It provides power to the starter slave solinoid.
Second....go to the crossconnect and find the black/white lead. It activates starter slave solinoid. Jumper it to 12v and see if the engine cranks.

If it does not, make sure the slave solinoid black lead is really grounded. It connects just above the black/white lead. If it is a good ground, you can measure the resistance of the solinoid winding, to be sure it is not open. Could be burnt or wire, or maybe a bad solinoid (which should not be due to the short circuit)....I would look for damaged or cut wires.

If the solinoid works, then follow the black white to the neutral safety switch, located at the front of the engine. If you did not plug that back in or if your shifter is not in neutral, the engine will not crank from the key switch.

If the circuit has continuity to the solinoid, then check for bad pins, pushed in pins, or wires disconnected from the pins of the round 14pin connector at the front of the engine.

If all is ok there, go to the key switch.
When you turn the switch to on...do the gauges come on? If so, you are getting power to the key switch. If not, check the 15 amp fuse on the engine. Again, make sure there is power at both sides of the fuse and it does not have corrosion.

Assuming there is power at the dash but not knowing if you have a shift box with the key in it or just a separate key switch and light panel...look for that black/white lead behind the key switch. You may have to back probe it with a test light and see if you light the light when you turn the switch to start. If you have the shift box, the black/white lead comes out of it to one of the connectors on the pigtails that are about 10 inches long. Backprobe there. Make sure you are connecting your test light to a good ground. Directly to your battery would be the best.

Let's see what you come up with, before I go off onto too many tangents.

Mike
 
OK so the multi meter and followed your advise on how to run through the problem and yes I feel abit sheepish now. Main 30 amp fuse even though replaced was not working?, took abit of figuring out "as it was replaced" but all sorted now. engine turns over and fires. Now only problem left is getting the boat trim to work. Power goes into the trim relay box at 12.4volts, the switch mechanism (blue/green/earth) has continuity when switched up or down but I am only getting 10 volts out to power the trim motor. the relay was clicking and sounded like it was shorting out when it had power to it - flicking on off on off really fast so I assume I have fried the relay box?? B y the way Mike aka hondadude you are "the Man"
 
Glad you found it fast.

As for the trim...
Have you measured the output to the trim motor without the trim motor attached?
Was there clicking at that time or only when the motor was connected?
If you are measuring the voltage going to the trim unit at the connector, does the voltage drop when you try to activate the trim.

The clicking could be a bad trim relay unit, but it could also be a bad connection or bad connector where it connects to the battery post on the starter or a bad connection at the connector near the trim relay unit.

You should also examine those ground wires for points where they may have melted or where it connects to the block. Make sure the connection is tight and good and clean.

The clicking sounds like a voltage drop when the trim motor is trying to draw a high amount of current. The no load voltage may read good, but under load, if there is a bad connector, wire, etc, the extra resistance will cause a voltage drop. The clicking may be happening by the first click of the relay being activated, but when the load of the motor is present for that first instance, it causes a voltage drop, which causes the relay to drop, releasing the load. Since you still have the switch pushed, that reactivates the relay again, adding the load, causing the voltage drop, dropping the relay, etc etc, etc, over and over again....thus the clicking.

Let's see what the results of you load and no load tests are...and we will go from there.

Again, if the motor was off and wires disconnected, they may not have been reconnected correctly. In general, the way you described the original short of the battery cable, it should not have hurt the trim unit....except for maybe melting the ground wires.

Mike
 
So far in regards to the trim motor - I have put 12 volt battery directly to the motor briefly and it turns on and trys to lower the outboard, I have tested the switch at the outboard for continuity and both blue/green wires have continuity when the trim switch is flicked to the correct side for the wire. I have measured the voltage from the main wire that runs from the starter to the trim relay box, using the black ground wire from the relay box - and it measures good at 12.4 volts which is the same voltage I get from the main battery wires itself. I have tested the power wire just as it enters the relay box and it measures the same. Measuring the voltage of the power out wires that run to the trim motor with the motor disconnected shows a voltage drop to 10 volts, and you can hear the relay almost sizzling, when connecting the power wires that run to the trim motor nothing happens - trim motor doesn't activate
 
and just ran out and tested the voltage under load - voltage from the power wire going into relay box with the trim motor connected voltage 12.3 volts, which drops to 2 volts when the trim up/down switch is activated either up or down and returns to 12.3 volts when switch is de activated. motor doesn't turn on. I didn't hear any relay clicks or sizzles at all this time with the motor connected or disconnected.
 
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If I understand correctly, the voltage going into the relay box is decreasing from 12.3 to 2. So the problem could be in the relay box, but I would run a wire jumper, of at least 12 gauge from the starter post to the connector and retest.

Mike
 
There are no Honda power trim relays in the country at present where I am and it likely will take some time to get one in.. I have heard they are just two standard car relays and I should be able to make up a duel relay set up? is there any truth to this>? if not how can I make one up?
 
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I guess you determined the problem is in the trim relay pack. There are 3 in Honda's parts center #10. I do not know where that is.

Yes, you can essentially duplicate the relay mechanism using car relays....as long as they are single pole/double throw and have high enough current rating.

Mike
 
There are two white leads that should be attached to the post at the starter solinoid. One of them goes to the 30amp fuse that you had trouble with.....and the other white lead goes to the trim relay box thru a connector that is at the end of a pigtail on the trim relay unit.

Mike
 
I have just tested the relay box out of the boat as per the manual. I have the correct continuity between the motor wires and the earth wires and the correct resistance between the earth and the switch wires. When I powered it all up directly to a 12 volt car battery the relay kicked in fine when I activated the switch and I had the correct voltage leaving the relay going to the motor with both the blue and green wires. SO I guess this means that my relay is fine and as you suggested the problem lies elsewhere
 
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Glad you have the manual. It helps a lot.

If that all checked out, then either your ground wire (black) going to the relay box or the white or both have an issue or do not have a good connection.

Mike
 
ok - now at long last everything works. I pulled back every wire. Took a nice metal file (no emery paper) and made every connection shine like the sun. Started at the battery and worked back (slightly loose neg terminal - sheepish grin :rolleyes:) through every earth, closed off my spade terminals for a tighter fit. anyway. funnily enough it works fine now Mike firstly I would like to thank you for your patience with me. I have done a fair amount on cars and never had an issue. I was fairly confident that all my grounding was pretty good but clearly it wasn't. To anyone trolling and researching these problems - ( and I honestly thought I had done this) clean your terminals, earths every thing first. SO again MIKE THANK you. you saved me $450 NZ that I was just about to shell out for a new relay. thank GOD I didn't. Now I can get on with the job I started doing.
 
Funny thing...it is always very simple....ONCE YOU FIND THE PROBLEM!

Glad things worked out.

I hope your next phase is a little less frustrating for you.

Mike
 
Yeah next phase is trying tl work out where 2l of oil is going to in a days fishing approx4 hours running at 45 00 rpm. Plugs clean. Mild blue smoke on start up. Some carbon around exhaust. Very very small leak top bottom crank seals. Engine runs smoothly good powere. Going to look at valve stem seals and crank seals
 
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