3.8L no crank/no start

[inthedirtagain]

Bought this 1981 Sun Ray last Fall and it started/ran just fine while when I winterized before storing (was the one and only time I ran it). Shut it down and haven't touched anything until now. Fast forward to this last month when I went to drain/replace all fluids and thought I'd listen to the radio at the same time. Well, I opened a can of worms. I had no power at the dash at all. None of my gauges worked, nor the tilt/trim, or horn. So began the tear down. The stereo wiring was horrendous, so I gutted the interior trying to chase bad connections. All bad/unused wiring was discarded and only what was needed for the boat to run was left in place. I found the two 50a glass fuses for the the tilt/trim and main harness and each tested fine with my MM. Not wanting to take a chance while on the lake, I thought it would be better to replace them with circuit breakers that can be reset. In doing so, I now have power back to the helm!
One problem solved, but another cropped up. Whenever I hit the tilt/trim or the starter, the voltage at the dash gauge (and confirmed with my MM at the battery drops from 12.6v to 4-ish and stays there until I disconnect the battery for a few minutes. Neither of my circuit breakers pop when this happens. My first thought is a stuck plunger in the starter solenoid, but before I buy anything of importance, I'm going to replace the battery cables and clean/condition the terminals after charging. Any ideas on where I should proceed from there? Advice is greatly appreciated!

 

[alldodge]

battery drops from 12.6v to 4-ish and stays there

Your seeing that and not smelling burning insulation? That's like a dead short.
For it to go that low and nothing burning there some major corrosion somewhere

Cleaning or replacing cables and cleaning is on target

 

[Bondo]

I'm going to replace the battery cables and clean/condition the terminals after charging.

Ayuh,...... This, ^^^, is probably where you should have started,......

A bad, dirty ground can cause voltage drop,.....

 

[Scott Danforth]

Also, after you go thru the electrical system and cleean all the connections, you will need to service the points

 

[inthedirtagain]

Sorry for the delayed response, but we've been celebrating my son's HS graduation for the last 2 weeks. Had a ton of family over, then we took a trip to the sand dunes with my dirt bike and a couple of UTVs. Been a great 2 weeks to remember before he ships out with the Air Force in September. So here is the latest, as of today....

Removed the old cables, made new ones, and cleaned the battery posts. I'm a fan of junction blocks at the helm AND on the battery, so I added top post blocks and connected the cables. Additionally, I wired up an Anderson plug to the blocks for a charge cable. Did this to my fishing boat's trolling motor and battery and to the solar panels/power inverter/charge controller on my camp trailer. Also cleaned up the wiring to the aftermarket fuel pump after checking polarity (+ and - not indicated). Turned the key and I not only have power at the helm, but also the tilt! Engine will crank over now, too! Need to troubleshoot the trim function. It'll go up, but doesn't go down and makes no noises. Any advice?

I got back to my original plans from over a month ago and drained all the drive oils and replaced with Merc Quicksilver Hi-Perf 90wt gear oil. That stuff has worked wonders in my fishing boats original Merc 1000ss. It has had a leaky LU since I brought it home and the Merc oil tolerates mixing with water much better than a regular gear oil. So, I drained and filled the LU, MU, and upper. One last question before I put it on the muffs and fire it up for the season: The lower unit has a small hole just ahead of the water intake. My service manual shows it there in pics, but doesn't describe its function. When I added oil to the LU, some oil weeped out of this hole. What's the hole there for?

 

[alldodge]

It'll go up, but doesn't go down and makes no noises. Any advice?

More bad connections or relay has crapped out

 

[inthedirtagain]

Fired right up! About that weep hole I mentioned........water squirts out of it when on the hose, but when sitting, I've got gear oil coming out. Any advice?

 

[alldodge]

Bad seal in the drive. Pressure test the drive with no lube and should hold 10 psi

 

[Bondo]

Fired right up! About that weep hole I mentioned........water squirts out of it when on the hose, but when sitting, I've got gear oil coming out. Any advice?

Ayuh,..... It's a case drain, to drain water, so it don't freeze, 'n crack,......

As you already know, there's an oil seal leakin',.....

 

[inthedirtagain]

fair enough. I'll look into that.