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b87 Black Max engine starting issues

Z

zam88

New member
"This is going to be a bit lon

"This is going to be a bit long.

I have a 1970 Stamas Boat with a 150 HP Mercury Black Max Engine.

The engine has been running fine for me, but the starting has been a real problem.

Last summer I'd been having issues with getting it started and had to move the throttle around while starting it to get the starter to "engage"

When it acts up you just turn the key and listen to absolutely nothing happen.

My engine shop and I thought this sounded like a neutral safety switch issue, and I had it replaced.

The boat did better the next time I was down there (though not perfect)... meaning that it was more consistently getting some action when starting rather than just the dead click.

But after that, it got even worse.

I called the shop back and said I wanted to get it checked out and see what the next step was towards making it work.. The starter seems fine, but something is keeping it from engaging.

They got back in there and cleaned and lubricated the starter, said it was gummed up with debris.... When I got down there this Thursday it was working like a DREAM! Almost 100% connection on the starter. By Saturday it was back to its old tricks again of not working.. by Sunday there were a few times when I wasn't even sure if I was going to get it going.

I talked to the shop again and they said the next move is to replace the entire control box.. a $300 part plus probably $200-300 in labor....


Before I do this:
1) does anyone have any other ideas?
2) will a new control box solve my problems?
3) will a new control box be compatible with a new engine if I purchased one?"
 
"Z,
Not sure what you mean by

"Z,
Not sure what you mean by control box, I have the same engine which I have been working on for a couple days. These things have two switchboxes (2 - three cylinder boxes) that control each of three ignition coils. The voltage comes from the stator which excites the trigger and sends the voltage to the switchboxes.
I would say that the starter not turning over would have nothing to do with this system since the starter gets its juice from the ignition switch care of the starter solenoid. If it's a matter of the engine simply not turning over I would start by checking the ignition key switch first, then proceed to the solenoid and check the starter itself for good wires. If these things turn too slow due to undervoltage they tend to not engage the bendix gear on the nose of the starter. If you hear nothing when you turn the key I would think the circuit from the key up to and including the solenoid would be an excellent place to start. You could also check the internals of the starter, the brushes and comutator could use an overhaul. If the brushes are gone, brush springs damaged, or the com. has burnt spots in it, this could all lead to nothing happening when you turn the key.

Actually, you could simply use a jumper from the hot side of the starter solenoid to the small post on the same sol. and this will engage the sol. and turn the starter. If this works consistantly, you have a problem before, like the key switch.

Hope I understood your simptoms correctly.
Good luck."
 
"Hi there!

Firstly, welcome

"Hi there!

Firstly, welcome to the forum! There are plenty of old Sea Dawgs here that have a wealth of expertise and knowledge.

When last did you check if the battery has full charge? How good is the discharge rate? How's battery terminals and condition of the wires leading to the motor?

There could be a voltage drop, hence poor starting?

Doug seems to be on the right track regarding the IGN SW, they're known to fail at some point...

When last you check the kill switch circuit? BLK YEL wire that runs from motor to control box, kills motor when grounded.

If there is a decent workshop near you, they might have a spare control box to test your rig with... Not too sure why they'd rip you so much on labour for such a simple job that would take an hour or three, max.

Not all control boxes work on any motor. You'd have to stick with same brand of motor as the control box, also, new motors are generally supplied with control boxes as a package.

If your workshop is pushing you to buy a new control box, find another shop. Maybe they have dead stock they're trying to move and will hope this would solve your problem...

Good luck!

Regards from a cold and wintery Johannesburg in South Africa!

Benjamin."
 
"Thank you for the replies so

"Thank you for the replies so far, let me answer some of the questions:

First Doug Wood:

By Control Box I mean the box that houses the starter and the throttle. This is an outboard engine and the cables run to this control box.

It is not a matter of the engine "not turning over", it is a matter of getting the starter to engage the engine. if I get it to engage the engine, it doesn't take too much to get it started.

But most of the time you turn the key, hear the warning beeps, then turn it and hear nothing happen.

Thank you for your reply


Benjamen: I've been to Johannesburg once, beautiful area.

I have a voltage meter hooked up to my batteries and (i have 2) and test them regularly, they are hovering around 12 volts.

I have not checked the kill switch circuit.

I know that I'd have to stick with a mercury control box, but what i was asking was if a new control box would operate both a '87 engine, or a brand new engine if I purchased one.

Thanks!

Any chance here this is a battery cable issue?"
 
"Hi there!

Ja, Jozi (&#

"Hi there!

Ja, Jozi ("Jaw-Zi" as we locals call it) is a great place to be. Weather is always good, BBQ's & people the best. Would have liked to be less dependant on oil... Have boat, suffer the consequences. Gotta take the bad with the good, hey?

If memory serves me right, you'd need closer to 13,8 volts. Meter might be out slightly though. Try the battery on you car os vice versa on the boat.

Of the control boxes, not too sure, I've been led to believe that at some point the terminations were changed. You'd only find out when you've seen the motor you intend on buying vs the new control box. Find out from a reputable dealer and ask to see it in action before hauling out those $$$$$$$$.

That warning you hear on switching on is an auto self-test. Just to remind you that the warning buzzer circuit is operational. They are prone to lulling you into a false sense of security... You've been warned now.

Once again, as Doug said, do an overhaul on that starter. Check it out carefully and we'll go from there. They are straight forward items to fix and maintain.

Good luck and keep us posted!

Benjamin."
 
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