Releasing Hydraulic Pressure

[TMW123]

Hi,

I have a 1998 50 HP Johnson with power trim/tilt. The trim motor has suddenly failed (Verified with multimeter) and the engine is stuck in the down position. The bypass valve is stripped and not turning. Will draining the fluid allow me to lift the motor manually?

Thanks

 

[Bosunsmate]

You may have to remove all the fittings so it can bleed elsewhere as you lift. Whether it will work, i suspect so but ive never tried

 

[jimmbo]

Do you have an Owners Manual?

I found this, it might have something relevent
http://boatinfo.no/lib/evinrude/manuals/1990-2001johnsonevinrude.html#/498

 

[TMW123]

Thanks for replying. I do have a Seloc manual which is not great (The relay test procedure was incorrect) but its better then nothing. I will definitely check out the link.

 

[boobie]

Remove the stripped bypass valve and see what happens.

 

[TMW123]

I don't know how to get it out. Should I just drill it?

 

[fireman57]

try unscrewing a line(s) then remove unit to drill it out. I would not use an easyout though as they tend to break and make matters worse. Try a reverse drill bit.. You will have to bleed the system anyway.

 

[TMW123]

Well, I ended up drilling it and using an extractor to get it out. I drilled it as wide as i could and put the largest extractor in there and was able to turn it out. It was quite stuck. Now, I need to access the motor. I know the pins are seized and i dont want to deal with them. Could I take the cap off, pull the piston out and split the assembly that way? Thanks

 

[TMW123]

Final update for anyone who has the same issue. I was indeed able to split the tilt pump assembly by removing the cap and pulling the piston out. This allowed me to change the trim motor easily. Few pointers:

1. Use a hand impact screwdriver to get the tilt motor bolts out. They will certainty snap or strip otherwise.
2. When the piston is out, cover the opening to avoid contaminants entering the reservoir while you continue to work.
3. When inserting the piston back into the cylinder, move the cap to the very top of the shaft and insert the piston into the cylinder only. Then, lower the outboard and adjust the angle of the cylinder accordingly until you can get the cap back on. Otherwise, you will not be able to get the cap on because it will contact the transom before it is flush with the cylinder.

Thanks for everyone's input.

 

[fireman57]

Great advice. As you can tell without everyone here seeing what you see it is difficult to diagnose.
Glad that you were not scared to try something. It's cool when someone looks at something and figures it out. With only 9 posts you have already contributed good advice. Stick around. Don't be a one and done like some are. It is a great forum. Not on here as much as I used to be due to age and some things passing me by but still enjoy reading and lurking.