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Jeff G.
Jeff G., Marine Mechanic
Category: Boat
Satisfied Customers: 4728
Experience:  42 years experience, Certified Master Technician, All Major Outboards, Sterndrives, Hi-Performance
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I have a 1988 150 hp VRO motor that the tilt was trash .I

Customer Question

Hi.I have a 1988 150 hp Johnson VRO motor that the tilt was trash .I bought a totally rebuilt tilt unit on Ebay for 420 dollars and had a mobil marine mechanic put it on.We ran it a few times and seemed to work fine.Today I tilted the motor up and and it went back dow about 9 inch.I raised it back up and it went down even more.I lowered it all the way down and it wouldnt come back up unless I had my wife it the tilt botton and I assisted by lifting.any sugestions?
Submitted: 2 years ago.
Category: Boat
Expert:  Jeff G. replied 2 years ago.

First thing is to check the fluid level. Tilt the engine all the way up and put the trailering legs down to support the engine. Remove the slotted fill plug from the back of the trim reservoir. Using something like a squirt oil can fill the unit to overflowing with Dexron ATF. Put the plug back in and operate the trim a couple times then repeat the fill process. The unit is self bleeding. It is possible that the unit got air in the system from shipping.

You may have to repeat this a few times.

If the unit is full. First check the manual relief valve. It is on the side of the trim unit accessed through a opening in the clamp bracket. Make sure it is firmly seated IN, clockwise.

If the unit is full and the manual relief valve is in then you may have an internal leak. You may want to contact the seller. I'm skeptical about the unit being totally rebuilt.

Try these and post back your results and we can go from there.

Customer: replied 2 years ago.
I did check the fluid which was full and also check the manual relief valve it was tight. still no luck.I am also skeptical about this being totally rebuilt.Amazing what a fresh coat of paint does to make something look new.I think there is some internal issue.
Expert:  Jeff G. replied 2 years ago.

If the trim is not externally leaking and is full then one or more of the valves are hung open. The hydraulics of the trim are one area I never recommend the owner mess with. Take the wrong part out and the hydraulic fluid can come out with tremendous pressure or small check valves can come out and you not even knowing it.

That being said, what you can do is to drain and refill the unit. I won't guarantee this will work but lets try this.

Tilt the engine all the way up and put on trailering legs.

Look into the cavity where the manual relief valve is, there is a single C clip. Remove the C clip. Holding a rag over the Manual relief valve and slowly remove the valve. When out put a large container under the unit to catch the spilled fluid. Examine the valve for any cuts or tears in the O rings. A kit is available from Evinrude for the trim that includes O rings.

If the O rings are not perfect, replace them.

Put the valve back in once the unit finishes draining. Check the old fluid for any signs of metal or contaminants.

Tighten the valve and refill the unit. Now try to operate the unit up and down a few times allowing the trim motor to cool between every few cycles. Keep the unit filled with fluid. If it doesn't come down when trimming down from air in the system, open the manual relief valve 2 turns to allow it to come down. Close it and try again. You may have to do this a few times to bleed all the air out of the system.

Once the air is out of the system see if the trim works and holds. If not then contact the seller. In more than half the cases this will cure the problem with new fluid and allow the bad check valve to operate properly. When used units are sold they are almost never overhauled unless there is a problem and if the guy isn't qualified then overhauling is about worthless. I certainly couldn't overhaul a unit and sell it for a profit at $420.

Try this and let me know how it does.