Tilt/Trim pump issues

[bently]

I own a '78 Glastron with a 470. It has a single selenoid trim pump with the three button set-up. I have just recently replaced both tilt/trim senders as the wires were corroaded and shot. The tilt/trim was working great until we ran back to the dock to re-supply and head back out but the motor would not trim down and was locked in the full up position. You can hear the pump running and it should not be out of fluid because it is all the way up. We pulled it out of the water and stood on the out drive while the pump was running and nothing still stuck. Drove two hours home let it sit in garage over night and now with the rams unhooked they slowly retrack with not weight on them. Could the valve assemble be full of crud, I have a used pump that I took apart to look at and the bottom of the resovoir is full of sediment, could that be my problem?

Thanks

 

[alldodge]

Re: Tilt/Trim pump issues

I own a '78 Glastron with a 470. It has a single selenoid trim pump with the three button set-up. I have just recently replaced both tilt/trim senders as the wires were corroaded and shot. The tilt/trim was working great until we ran back to the dock to re-supply and head back out but the motor would not trim down and was locked in the full up position. You can hear the pump running and it should not be out of fluid because it is all the way up. We pulled it out of the water and stood on the out drive while the pump was running and nothing still stuck. Drove two hours home let it sit in garage over night and now with the rams unhooked they slowly retrack with no weight on them. Could the valve assemble be full of crud, I have a used pump that I took apart to look at and the bottom of the resovoir is full of sediment, could that be my problem?

Thanks

You could be low, check your fluid reservoir. Once all the air is out the trim cylinders are full of fluid on both sides, fluid just gets recirculated. The rams retracting without weight could be air could be crud and sediment. Look at the color of fluid in the system and this should help in determining what may be wrong.

 

[bently]

Re: Tilt/Trim pump issues

I took my pump out of my boat cleaned the sediment out of the tank put new "O" rings in the trim rams and reinstalled the pump with new clean hydrolic fluid. The pumps runs well up and down but now it will not go up. I can lift the outdrive and the fluid will fill the trim rams from the low pressure side and hold it up. I can then hit the down button and it will trim down, but will not move up when I he the trim up. I am keeping an eye on the fluid level in the tank and it is not low. It is funny, I could not lower the outdrive before not it won't go up, what am I missing?

Thanks

 

[alldodge]

Re: Tilt/Trim pump issues

I take it the pump is running it just will not go up now. You probably have some crud in the check valve areas of the pump or reverse locking check balls.

http://cemrweb.cemr.wvu.edu/~mathews/boat/pdf/manual/Chapter Eighteen.PDF

 

[bently]

Re: Tilt/Trim pump issues

Yah, the pump is actually running well and sounds strong, there was some "stuff" in the tank that I cleanded out. I suppose there is no way to flush the valve assembly with out removing the pump and actually taking the inner pump plate apart. I took the used one apart and there are three ball bearings that were hard to get back into place, my luck they would not reassemble well on my good tilt/trim pump. The fluid flows through the revers lock as there is a plastic tube that you can see the fluid flowing through. I think my problem is in the valve assembly in the bottom of the tank.

Thanks

 

[bently]

Re: Tilt/Trim pump issues

Still struggling with this issue, anyone have info on flushing the valve assembly.

Thanks

 

[alldodge]

Re: Tilt/Trim pump issues

Still struggling with this issue, anyone have info on flushing the valve assembly.

Thanks

When a hydraulic systems starts messing up it needs parts replaced. Mosture seattles in the bottom of areas and rust starts. Just like machinery it hates to just sit. You may be able to run some transmission fluid through but I'm guessing it may not help. Best bet is to get a rebuilt valvle body of another pump. Either way I see the pump needs to come out to clean and or replace.

 

[bently]

Re: Tilt/Trim pump issues

We'll I fixed it, I didn't think it was a rust/corrosion issue. I took the trim pump out again and opened the metal tank and found a small ball bearing in the bottom where it shouldn't be. One of the allen screws did not have enough pressure on the spring holding the ball bearing on its seat. I took the valve assembly apart and placed the ball on the seat and reassembled and walla, it works. It was free of rust also nice and clean.