One of my Alpha 1 hydraulic hoses sprung a leak at the fitting that goes into the pump. I thought it would be an easy replacement, but after unscrewing the hose from the pump, it appears the other end of the hose goes out the transom and in to the outdrive. Is there an easy trick to replace this hose, or does the outdrive need to pulled to do this?
How to replace trim hose Alpha 1
- Thread starter GJarrett
- Start date
dogturd21
New Member
I would not call it an "easy" trick but there is a trick to it. The drive does not need to come off. The trick is to either use a "fish line", or the old hose, as the "fish": i.e. the technique of pulling a line through using another line. The hose is already in place. First off, number the hoses so that you can tell which is which to the pump, and to the manifold fitting on the bottom of the outdrive. Like #1 and #2, although I think they are "in" and "out". Many times they are different colors like black and tan. Also, you need to determine if you have the Mercathode system or not. At the bottom of gimbal housing there will be a manifold where the trim pump hoses go in, and the trim ram hoses also go into. Its easy to find on the outside because that is where the hoses lead from the trim rams. There might be the Mercathode thingy to remove, or a anode (zinc) first. There might even be just a block-off plate if you have neither. But if you unbolt that manifold, you can drop it a small distance or pull it away and get a small amount of play in the hoses. Make sure you use flare wrenches when working on any of these fittings.
Once the hose is unbolted from the manifold you can tie a strong line (very strong line !!) and when pulling the hose the line will come with it. different engine compartments can lead to a bit of puzzlement as to the best way of "fishing" the line through- either pulling into the engine comparment, or pulling out through the transom - gimbal housing. I have done 2 of these, and I cannot say which is more correct, but I think pulling from engine compartment is easier. Also, be prepared to replace the manifold if there is any corrosion of the part- its aluminum and I recall its about $50 or so. for lack of a better example, go on ebay and search for listing 321340736150 (keep in mind this is March 2014 msg and that listing number if only good for a few months).
I have had a few mechanics insist the engine needs to be pulled before I refreshed their memory about the fish method.
Once the hose is unbolted from the manifold you can tie a strong line (very strong line !!) and when pulling the hose the line will come with it. different engine compartments can lead to a bit of puzzlement as to the best way of "fishing" the line through- either pulling into the engine comparment, or pulling out through the transom - gimbal housing. I have done 2 of these, and I cannot say which is more correct, but I think pulling from engine compartment is easier. Also, be prepared to replace the manifold if there is any corrosion of the part- its aluminum and I recall its about $50 or so. for lack of a better example, go on ebay and search for listing 321340736150 (keep in mind this is March 2014 msg and that listing number if only good for a few months).
I have had a few mechanics insist the engine needs to be pulled before I refreshed their memory about the fish method.
Wow. Thanks for the help! Please bear with me and clarify something clearly for me, because I'm a total newbie to outdrive maintenance and don't want to screw something up.
I had actually thought of trying something like that (but have never seen the inside of an outdrive) so I have been careful not to do something that will make my situation worse. This morning I had taken off the anode at the manifold you describe where the trim ram hoses go into. There are two nuts that hold it onto the outdrive but it was stuck really bad. I had to carefully hammer a chisel between the manifold and the outdrive to wedge it off of the outdrive. As soon as it started to break loose, it started leaking fluid out (power/trim? gear?). I thought that meant that whatever was above the manifold was a holding tank of sorts, so I quickly re-tightened it back onto the outdrive because I didn't know what I was getting in to.
Just to clarify what you wrote: if I go ahead and drop that manifold, I will find that the top of it that is inside the outdrive will have the other end of the hose bolted directly into the manifold and all I have to do is unscrew the other end, then fish the hose one way or the other to install the new one... and unbolting / dropping the manifold won't hurt anything. Right? If so, I'll try again this weekend.
Thanks again for your help!
I had actually thought of trying something like that (but have never seen the inside of an outdrive) so I have been careful not to do something that will make my situation worse. This morning I had taken off the anode at the manifold you describe where the trim ram hoses go into. There are two nuts that hold it onto the outdrive but it was stuck really bad. I had to carefully hammer a chisel between the manifold and the outdrive to wedge it off of the outdrive. As soon as it started to break loose, it started leaking fluid out (power/trim? gear?). I thought that meant that whatever was above the manifold was a holding tank of sorts, so I quickly re-tightened it back onto the outdrive because I didn't know what I was getting in to.
Just to clarify what you wrote: if I go ahead and drop that manifold, I will find that the top of it that is inside the outdrive will have the other end of the hose bolted directly into the manifold and all I have to do is unscrew the other end, then fish the hose one way or the other to install the new one... and unbolting / dropping the manifold won't hurt anything. Right? If so, I'll try again this weekend.
Thanks again for your help!
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Bt Doctur
Well-Known Member
dogturd21
New Member
What probably happened is that you have a leak of the trim manifold (part E), or the hose near the manifold. This exact same thing happened to my Bravo 3 last year (I think the manifold part numbers are identical to the Alpha Gen II but not positive). The illustration that Bt Doctor post is excellent: the hand is holding onto the wire for the Mercathode electrode. What can happen is that you can get some corrosion where the flare (pipe) nuts screw into the block, and they will slowly corrode and cause a leak. The trim pumps run at a ultra high PSI and if this connection is weak it can blow the hose off of the block. The result is your trim does not work, and you get fluid pumping back into the bilge.
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Thanks to both of you. I just ordered both hoses (if I am doing one, might as well do the other because it probably isn't far behind failure either) and expect to get them in time to work on it this weekend. I'll let you know how it goes. I sincerely hope that the manifold is okay and I don't have to get one of those too.... I'd like to get this job over with in the same day once I start.
I'll let you know how it went next week. Thanks again.
I'll let you know how it went next week. Thanks again.
dogturd21
New Member
I would advise replacing the manifold- The hard thing about replacing the trim manifold itself is the Mercathode electrode and the hoses: if you have the Mercathode you have to pull the wires just like the hoses. Find the correct part number and search around: I found the prices on that part range all over the place. Another piece of advice: once the boat is in the water, monitor both your bilge for fluid leaks, your trim pump for leaks or water intrusion, and the outside water above the drive: the fluid / oil will rise to the surface if its leaking outside. Once I replaced my manifold, one of my trim rams started leaking at the hose fitting. A marine mechanic I know warned me that this could happen and he advised me to replace the trim rams at the same time: due to the cost I elected to risk it- and lost the bet 
If your boat is trailered its not that big of a deal, but my boat is kept in a slip and I have to pay to have it hauled out.
If your boat is trailered its not that big of a deal, but my boat is kept in a slip and I have to pay to have it hauled out.I don't think I have Mercathode - I did find a Mercathode wire in the bilge, but it is not connected to anything and there's not an electrode below the manifold; just a regular anode. This boat did have an engine swap (it's a '99 boat with an '09 engine) so I wonder if it originally did have a Mercathode system but it wasn't kept when the swap was done. I replace the trim rams last year so they're practically new. I'll just roll with this and see what happens. Fingers crossed.
FYI my boat is trailered and 85% freshwater use, with just a couple of trips to the ICW saltwater per summer planned.
FYI my boat is trailered and 85% freshwater use, with just a couple of trips to the ICW saltwater per summer planned.
I tackled this job today and thank all of you for your help. I bought both hoses so that I would not have to worry about the other one.
I did get both hoses fished through - going from the outdrive into the engine bay was the easiest route and worked okay with a little bit of work. The manifold did break at the hose connection so I will have to order a new manifold. If anyone has a suggestion for an internet supplier with a good price for an item like that, I'd appreciate it
I did get both hoses fished through - going from the outdrive into the engine bay was the easiest route and worked okay with a little bit of work. The manifold did break at the hose connection so I will have to order a new manifold. If anyone has a suggestion for an internet supplier with a good price for an item like that, I'd appreciate it
