MC-1 hydraulic line blockage? I think...next steps?

[deerhuntre]

I've narrowed down the issue to some sort of hydraulic line blockage or problem in the TRIM DOWN. With the outdrive in the up position, I've disconnected the hydraulic line closet to the transom outside the boat and the outdrive lowered. At With those lines disconnected, the trim pump ran just fine. However, with those lines connected, the trim pump is not able to run in the down direction.

Questions: Do these lines become blocked or is the lockout mechanism likely requiring service? What can I look at or how can I diagnose this and what are the next steps?

250 ci 165 inline 6.

Thanks!!

 

[achris]

Re: MC-1 hydraulic line blockage? I think...next steps?

Couple of things it could be...

If the pump is running but not driving the leg down, then the reverse lockout valve might be out of adjustment
If the pump is not running, look for an electrical problem... (you didn't say if the pump is actually running or not, with the lines all connected.)

Chris.

 

[smoedog]

Re: MC-1 hydraulic line blockage? I think...next steps?

Raise the outdrive and disconnect both actuators from the drive. Then "lower" the outdrive with the pump... Both actuators should retract fully... Maybe not at the same time but theyshould fully retract... You might have a seal that is getting pinched.

 

[deerhuntre]

Re: MC-1 hydraulic line blockage? I think...next steps?

More info: The pump runs just fine in both directions with the hydraulic lines disconnected at the transom. However, with the hydraulic lines connected, the pump tries hard to run in the down but just can't move hardly at all, maybe a second of struggling before stopping. The pump moves the outdrive up just fine with the hydraulic lines connected.

Given the above extra info, should I still perform smoedog's suggested 'pimched seal' test?

 

[achris]

Re: MC-1 hydraulic line blockage? I think...next steps?

More info: The pump runs just fine in both directions with the hydraulic lines disconnected at the transom.

And sprays fluid everywhere, yes?

However, with the hydraulic lines connected, the pump tries hard to run in the down but just can't move hardly at all, maybe a second of struggling before stopping.

The pump stops running? That sounds electrical.

The pump moves the outdrive up just fine with the hydraulic lines connected.

Given the above extra info, should I still perform smoedog's suggested 'pimched seal' test?

I would be getting some hydraulic gauges on that system about now...

 

[deerhuntre]

Re: MC-1 hydraulic line blockage? I think...next steps?

Regarding electrical and the pump stopping, I was testing by jumping the thick blue to the red power at the solenoid. The pump tried to run and quickly slowed to a halt as if it could not move the fluid. It sounded like it was struggling to run. That's how it sounded to me.

Alright, more testing.... I'll have to get hydraulic gauges and report the results as soon as I can.

 

[achris]

Re: MC-1 hydraulic line blockage? I think...next steps?

The blue (like the sky) wire is UP .... Green (like the grass) is DOWN...

And if it's the UP circuit loading up, then I would be checking the reverse lock valve....

At this point I'll ask you for more information about your set up... MC-1 covers a lot of years... Do you have gimbal mounted senders or the older hydraulic ram sender (for the trim gauge)? And have you located the reverse lock valve? Do you have the Merc service manual?

 

[deerhuntre]

Re: MC-1 hydraulic line blockage? I think...next steps?

Uh oh? Maybe I need to go take a photo. On the solenoid, I jumped the thick red to the thin non-black on the front and the drive went up. I then jumped the thick red to the thick blue on the side of the solenoid (opposite the thick red) and the drive did not move and that is when the pump tried to run and could not move more than a second. Is this incorrect?

 

[achris]

Re: MC-1 hydraulic line blockage? I think...next steps?

Uh oh? Maybe I need to go take a photo. On the solenoid, I jumped the thick red to the thin non-black on the front and the drive went up. I then jumped the thick red to the thick blue on the side of the solenoid (opposite the thick red) and the drive did not move and that is when the pump tried to run and could not move more than a second. Is this incorrect?

Sounds like you got the drive all the way up and then it got to the top of travel and loaded up..... You activated UP both times... There is no solenoid for DOWN, the current runs from the switch panel....

Chris.........

 

[deerhuntre]

Re: MC-1 hydraulic line blockage? I think...next steps?

Oh! OK, wow! That really explains a lot! That make sense given the behavior I observed. OK, then how can I activate the DOWN at the transom by jumping stuff to make sure its working?

 

[achris]

Re: MC-1 hydraulic line blockage? I think...next steps?

Pull the connector out and jump the red and GREEN....

 

[deerhuntre]

Re: MC-1 hydraulic line blockage? I think...next steps?

Oh, ok! The red plug-in connector on the front, right?

So, just to confirm the action at the solenoid: When I applied power to the small non-black on the front of it, is it correct that the solenoid then did its job and sent power to that thick blue that is opposite the thick red? Does that test verify the solenoid is working correctly?

Thank you so much for your help, by the way.

 

[achris]

Re: MC-1 hydraulic line blockage? I think...next steps?

Oh, ok! The red plug-in connector on the front, right?

Correct

So, just to confirm the action at the solenoid: When I applied power to the small non-black on the front of it, is it correct that the solenoid then did its job and sent power to that thick blue that is opposite the thick red? Does that test verify the solenoid is working correctly?

yes...

 

[deerhuntre]

Re: MC-1 hydraulic line blockage? I think...next steps?

Results so far:

I tested at the red connector..unconnected the connector to the dash switch. Applied power to GREEN and drive moved. I then applied power to thin blue, drive moved. There seems to be a short in the wires between the dash switch and the red connector because that testing resulted in the problem. Also, the PO did not have any fuses in this circuit. Arg! So, I'm fixin' that straight away along with running new wires to the switch.

Please share if there are any pitfalls or safety items I should be aware of for this operation.

Thank you!!

 

[deerhuntre]

Re: MC-1 hydraulic line blockage? I think...next steps?

After I ran new wires from the dash switch to the harness, the trim worked! Somehow the wires shorted out and I also installed a fuse in the system.

Again, thank you for all your help! My boat is back in working order and I'm just loving this motor!!