Re: Filling the Tilt/Trim System
I apologize for the vagueness of my previous post. I was in a hurry to get to work.
I took the system apart because it had started to take on water during my last trip to the river. Prior to that it had been working fine. I rebuilt the system using the kit that I bought from your eBay store. When doing the rebuild, I followed your instructions to the letter and checked every o-ring for proper size as I put them on. I flushed the lines out using the ram to suck up mineral spirits before disassembly as you suggested in a previous post and then blew the lines out using compressed air until no fluid came out. I also replaced the pump with one purchased from DB Electrical, since the old one was getting very corroded anyways. It came with 3 drive shafts. I checked each one to ensure it would engage the valve body. One was too long, one was too short, and so I selected the middle size. When I put the system back together, I put everything back exactly as it came off. The fluid that I am using is ISO 32 hydraulic fluid, as you had previously suggested.
Thank you for your response and I apologize again for the vagueness of my previous post.
iso32 is designed to release air bubbles quickly and absorb transient moisture as might happen with condensation on a cool night. So the milky color means there is still water somewhere.
My kits on ebay only go up through 1991. I finally found a place that carries a debris wiper to fir 1992-1995 but they are still on backorder. This matters because force trim systems did not use drive shafts prior to 1992. If you used a 1991 seal kit on a 1992 tilt ram and forced the cover to fit then it is not any good and has to be redone. I have the body seal but the debvris wiper is going into its second month of backorder.
So let's assume that you have a 1992. That yould be the tall skinny motor with a square base and four ports pointing directly down towards the ground. Great pump. But it has zero tolerance for debris. having to help the system up as you describe is common with 120-150HP 1992-1995 force. mercury used cheap atf fluid and the big engines generate enough backpressure to impregnate the rubber and the trim piston ring splits. If you fixed the trim piston ring then your lift problem is probably debris in the pump. The pump you have is not like the prestolite. It is a very easy pump to work on and fairly DIY friendly. All you need to do is take it apart and find the little flake of debris that is jamming one of your valves. Just make sure to work in a clean area and hold things inside of a large tub when disassembling. The aluminum cylinder is your pump and it is held down by the single black bolt. the three little hex bolts hold the top aluminum to the bottom. When lifting aluminum of black base springs will pop out. Do it slowly without tipping over so that you can put it back together in correct order.
The grinding could possibly have been you gears. if the lubricating film gets washed away by water then they can burn and score. Probably not the noise you hear. But tread with caution to avoid this. It is fatal to your pump.
regarding fluid - ISO32 is best but 1988-1992 engines have a tendency to buck if the fluid is too thin. For those engines, ND30 is the safe fluid since it doesn't buck. Most other years hydraulic oil is best choice because of longer rubber life, absorption of moisture, and ability to release trapped air.