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Need Help with 1975 Johnson 135hp Power tilt/trim

S

SaltyScot

Regular Contributor
135ETL75E

I just bought a boat with this motor, and it goes up but not down with the switch on the throttle arm. I tried a new relay and that didn't work. I tried applying 12V to the blue wire coming from the tilt motor and IT WORKED. I figured it had to be a bad switch or wire, so I bought a new surface mount switch and connected it to the 3 wires under the dash(where the throttle arm switch were connected) and still same. So I thought it has to be a corrupt blue wire from the switch to the relay and replaced that. It still doesn't work. I don't know what else it could be. Any ideas?

I imagine bypassing that side of the relay to run a wire directly up to the switch would probably melt something without a resistor or diode or something else I don't understand inline

Stephen.
 
The solenoid is for UP with the BLUE wire.----Down does NOT use the solenoid.----Sounds like it is not wired correctly.
 
SaltyScot said:
135ETL75E

I just bought a boat with this motor, and it goes up but not down with the switch on the throttle arm. I tried a new relay and that didn't work. I tried applying 12V to the blue wire coming from the tilt motor and IT WORKED. I figured it had to be a bad switch or wire, so I bought a new surface mount switch and connected it to the 3 wires under the dash(where the throttle arm switch were connected) and still same. So I thought it has to be a corrupt blue wire from the switch to the relay and replaced that. It still doesn't work. I don't know what else it could be. Any ideas?

I imagine bypassing that side of the relay to run a wire directly up to the switch would probably melt something without a resistor or diode or something else I don't understand inline

Stephen.
Click to expand...
I can’t figure out how to post a question I can’t seem to find how to do it? Figured it out.!! 🤙
 
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Obviously, i haven't reattached the blue wire yet since i jumped it.

Are the red and blue reversed?
 

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Clearly stated that blue is for UP.-----And the solenoid is only used for UP.------I don't understand why folks are often confused with wires and 12 volts.-----Look over your wiring diagram carefully and hook it up according to that.-----Red is power from the battery and thus the other red is power from the battery up to the trim switch in the handle !
 
racerone said:
Clearly stated that blue is for UP.-----And the solenoid is only used for UP.------I don't understand why folks are often confused with wires and 12 volts.-----Look over your wiring diagram carefully and hook it up according to that.-----Red is power from the battery and thus the other red is power from the battery up to the trim switch in the handle !
Click to expand...
Yup, you were right as usual! The chassis ground of the relay was actually going to the positive side of the battery. The way the wiring was made it difficult to tell. Now it's good up and down. The seller dropped the price $500 when I showed up because of that. Have you ever wondered how much total money you have saved people over the years? That number might be staggering. Thanks again.:)
 
I have an older omc seadrive. Tilt trim motor stopped working so I ordered a new one and I can hear the relays clicking and tested the relays but motor will non come on….. haven’t checked wires on solenoid. Could that be the issue? Thanks
 
The 2 square black relays when in the relaxed position (in other words, not pushing either trim button) connect each trim pump wire (green down & blue up) to ground continuosly.
When you operate a trim button only the associated relay operates & connects that pump wire to 12v positive & the pump operates.
Conversely, operating the other trim button connects the opposite wire to 12v positive & the pump works in the other direction.
So the relays can click but fail to pass current thru the contacts inside. If wet, probably both sets of contacts are bad. To clarify, THERE ARE 2 SETS OF CONTACTS IN EACH RELAY. 1 OR BOTH SETS CAN BE FAULTY IN EACH RELAY YET THE RELAYS WILL CLICK & FOOL YOU.

You say early on that it does run in the up direction.
Applying 12v to green should operate it down. If not, the pump is bad. A 3 wire pump CAN fail in 1 direction & operate in the other.
 
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I just realized you have an old fossil with solenoids & not relays, so disregard the above post.

Back to post #6; it doesn't matter which large post gets red or blue wire. When the solenoid is operated. Current passes straight thru from post to post. Or should I say current is SUPPOSED to pass thru. Just like the relays I talked about above, or is possible that solenoid clicks but fails to pass current. Remember you may see 12volts on a meter but fail to pass enough current to operate the pump.
Regarding the pump: You should have a 3 wire pump, Blue/Green/Black. Simply apply 12v positive to either blue OR green wire. BE SURE NOT TO APPLY 12V POSITIVE TO BOTH AT THE SAME TIME. The black should go directly to a ground stud. With 12 bolts applied, pump should run. Test the opposite color, pump should run again. NOTE: It is not necessary to remove the wire from the solenoid to do this test.
I'm not seeing your boat but you may only have 1 solenoid, the 1 in the picture with a blue wire. This 1 is for trim up. Trim down pulls less current & may not use a solenoid.
 
Droid said:
I just realized you have an old fossil with solenoids & not relays, so disregard the above post.

Back to post #6; it doesn't matter which large post gets red or blue wire. When the solenoid is operated. Current passes straight thru from post to post. Or should I say current is SUPPOSED to pass thru. Just like the relays I talked about above, or is possible that solenoid clicks but fails to pass current. Remember you may see 12volts on a meter but fail to pass enough current to operate the pump.
Regarding the pump: You should have a 3 wire pump, Blue/Green/Black. Simply apply 12v positive to either blue OR green wire. BE SURE NOT TO APPLY 12V POSITIVE TO BOTH AT THE SAME TIME. The black should go directly to a ground stud. With 12 bolts applied, pump should run. Test the opposite color, pump should run again. NOTE: It is not necessary to remove the wire from the solenoid to do this test.
I'm not seeing your boat but you may only have 1 solenoid, the 1 in the picture with a blue wire. This 1 is for trim up. Trim down pulls less current & may not use a solenoid.
Click to expand...
Mine only has 2 wires yellow and blue.. so can I just touch the yellow or blue wire to the positive terminal on battery?
 
I don't know what a Calco pump is but a yellow is an odd ball.
Perhaps the 3rd wire is going to chassis ground at the pump mount or internally at the brush holder, IDK.
There are only 2 ways to reverse the rotation, either thru separate windings using 3 wires (even if 1 goes to ground at the brush holder so you can't see it) which is the early system OR by reversing the polarity of the 2 wire connection thru 2 relays which is the later system. ****Not applicable in this discussion are even later production motors (Etec) that use 1 large relay that basically has has the 2 individual relays in 1 housing. The pump motor is still a 2 wire type.

Your pump runs up by applying 12volts to the blue wire so it is getting ground somewhere. So 12 volts to yellow should operate it down.
Again I'm not seeing your boat & can only guess what 50 years of who did what looks like in person. But I do know that can style solenoid can't reverse the current.
 
I'm wondering if it's an aftermarket unit, maybe like a CMC?

Also, back in 1975 they had a tilt unit & a trim unit. 2 totally different animals. Didn't they both use the toggle switch on the dash and NOT a switch on the throttle handle?
 
Droid said:
I don't know what a Calco pump is but a yellow is an odd ball.
Perhaps the 3rd wire is going to chassis ground at the pump mount or internally at the brush holder, IDK.
There are only 2 ways to reverse the rotation, either thru separate windings using 3 wires (even if 1 goes to ground at the brush holder so you can't see it) which is the early system OR by reversing the polarity of the 2 wire connection thru 2 relays which is the later system. ****Not applicable in this discussion are even later production motors (Etec) that use 1 large relay that basically has has the 2 individual relays in 1 housing. The pump motor is still a 2 wire type.

Your pump runs up by applying 12volts to the blue wire so it is getting ground somewhere. So 12 volts to yellow should operate it down.
Again I'm not seeing your boat & can only guess what 50 years of who did what looks like in person. But I do know that can style solenoid can't reverse the current.
Click to expand...
Sorry blue and green… touched blue wire to battery and sparked..
 
In post #1 you said:
"I tried applying 12V to the blue wire coming from the tilt motor and IT WORKED"
Now you say it sparked. Understand this is pulling lots of amps & it will spark as it is touched together. Dies it run or not?
Did you try 12volrs to green? If yes, what did it do?
 
Droid said:
In post #1 you said:
"I tried applying 12V to the blue wire coming from the tilt motor and IT WORKED"
Now you say it sparked. Understand this is pulling lots of amps & it will spark as it is touched together. Dies it run or not?
Did you try 12volrs to green? If yes, what did it do?
Click to expand...
Sorry for the confusion but it did not work. And no I didn’t try the green wire. And didn’t run with the blue wire but maybe I didn’t make good contact. When it sparked u pulled away
 
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