Tilt Motor Slow when both relays connected

kbelky

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I have a weird issue, which I am assuming is a wiring snafu. I installed two new tilt motor relays on my motor (1977 70 HP Johnson). The motor flies up and down; but, only when I have one of the relays connected. With both relays connected, it moves at a snail's pace. The following is how I have the relays wired up:

Pin 30 - 12 AWG going to motor
Pin 86 - 14 AWG going to switch
Pins 85 and 87 - 14 AWG - each of the 4 wires going to power block
Pin 87A - 12 AWG - each of 2 wires going to negative block

I am using relays from the posted link.

So, do I have something wired wrong? Or is it normal for dual relays to cause a slowdown? There were no relays on the UP or DOWN for the tilt when I purchased the boat. So, this is all new wiring.

Thanks for your help!
 

sam am I

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There were no relays on the UP or DOWN for the tilt when I purchased the boat. So, this is all new wiring.

Wait, so how did it work before you bought it? or did the PPT not work ever and it was pre-wired and never used? This is why you claim they're "new wires"?

or

"new wiring" to you only? It must of had relays in order to have worked prior to you owning it, the relays were just removed before you go the motor?

I'm confused...........

Also, how many wires are coming out of the PPT motor..............2? or 3?
 

TBarCYa

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Based on the description you appear to have them wired correctly but what I can't tell is how the switch is connected to the relays. Does the UP terminal on the switch go to one relay and the DOWN terminal go to the other?
 

sam am I

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Based on the description you appear to have them wired correctly

No.....if 86 is "going to switch" as OP reports, the SPST up/down switches then feeds to each relay and is a switched 12V signal source via the red/white power wire.(See below)

85's therefor should be grounded.

OP reports he's ran 85's (along with 87's) to the "power block". I assume being a "power block", this is then 12V?

If so, won't work!!

Wired correctly as seen below...

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TBarCYa

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No.....if 86 is "going to switch" as OP reports, the SPST up/down switches then feeds to each relay and is a switched 12V signal source via the red/white power wire.(See below)

85's therefor should be grounded.

OP reports he's ran 85's (along with 87's) to the "power block". I assume being a "power block", this is then 12V?

If so, won't work!!

Wired correctly as seen below...


If the red/white in your drawing goes to ground then his relays are wired correctly and should work and since the relays are working individually, there must be a ground coming from somewhere to energize the relay. Based on the fact that the relays are getting energized, I would have to assume that the trim switch is switching ground and not +12v.
 

sam am I

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Good point and not knowing, a good assumption as well however, I cheated!!! The Johnson manual/s show a red/white wire feeding 12V to the up/down switches in two relay, two wire PTT motor setups.

My drawing was just a reference for the standard stock two relay setup and added for the discussion as switching ground/s here isn't typical, I have no clue what hes got at this point...........

I'm thinking his wiring/system is pretty messed up, enough to do odd things based on the post, hence my questions and why its working oddly......A "77" motor shows a three wire PPT motor which uses a solenoid, NOT relays.

That is IF he's running a two wire PTT motor?, Then the system is a two relay "H" bridge config and the drawing reflects the stock/standard wiring as such and then should, as per the manu, switch 12V through the up/down circuit.

Mixing a two relay H bridge config with a 3 wire PTT motor isn't going to work, not normal anyway.....So its a crap shoot unless he pipes up.....

"There were no relays on the UP or DOWN for the tilt when I purchased the boat. So, this is all new wiring." This statement alone, esp "new wiring" on a "77"? Makes me also wonder what going to happen when the horn is used....
 
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sam am I

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This method is used to reduce arcing over the contact in the relay but for this application???

Arc would be identical in the contacts regardless of switching ground or 12V at the coil.

Identical arc (less polarity) as well if the relay contacts themselves are switching ground or 12V to the motor.

Arcing is not polarity dependent(less dampening techniques, active/passive), test this by turning on your headlights, then disconnect you car's battery +/- posts each in turn, the arc on the "+" post will be the same as the "-" post when making and breaking the circuit......
 
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The Force power

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Your are absolutely right!
I was thinking of the scenario when the relay was installed on the ground-circuit from the trim-motor
 

TBarCYa

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This method is used to reduce arcing over the contact in the relay but for this application???

I was thinking safety... If it's an aluminum boat and the wire chafes against the hull it could short and potentially cause a fire. Of course, that was just a guess.
 

kbelky

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Well, I'm not the brightest bulb in the pack. I appreciate the feedback; but, the lingo is quickly getting over my head. Which makes me think I'll need to take the boat to a qualified repair shop. However, I can answer at least a few of your questions.

1) When purchased, the boat had a tilt motor which operated correctly. However, it had no relays at all. Thus, the reason I am adding relays.

2) Yes, I meant a 12v power block.

3) I have rewired the entire boat, including the tilt motor wiring. Everything works great, except for the tilt motor going up and down very slowly.

4) The tilt motor is a 3 wire: Blue, Green and Black. I have Blue going to pin 30 on the up relay; Green going to pin 30 on the down relay; and Black going to ground.

5) The switch up position is wired to pin 86 of the up relay. The switch down position is wired to pin 86 of the down relay. The center post of the switch is wired to ground.


Again, I appreciate any advice you can give. :)
 

sam am I

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4) The tilt motor is a 3 wire: Blue, Green and Black. I have Blue going to pin 30 on the up relay; Green going to pin 30 on the down relay; and Black going to ground.

Wait, don't pay anyone shet just yet!!! Okay so custom wired...sorta,

A grounding signal from the up/down switch to energize the relays coils is fine (not standard however) BUT, running the relays with a 3 wire PPT motor is the problem!!

A 3 wire (center tapped) motor is suppose to, for example, have it's blu wire float if the grn wire is powered (going down) and vice versa (grn wire float if the blu wire is powered[going up]) ................

The relay setup doesn't allow this, it keeps the UN-energized (blu in our example above) side grounded when the other side (grn in our example above) is powered

Sooooo, by pulling a relay, as you have discovered (blu's for example) works because its allowing (emulating a solenoid) the blu side to float when grn's relay is powering the motor...........

The fix? Disconnect/snip 87a from ground, let'um float...........See "X's" on 87a's below

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kbelky

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That, indeed, fixed my issue!! I am guessing this boat originally came with a 2 wire motor; but, the previous owner changed it out to 3-wire. I wasn't even aware 2 wire motors existed; so, I thought they all used relays with the same wiring setup. :) In any event, pulling and snipping the 87a connections for both relays has the motor flying up and down again!

Thank you so much for the help!!
 

sam am I

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You're very welcome, glad all is well and thanks for closing the loop, this'll help with all that might come in search of. :thumb:
 
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