Greetings and salutations. This is my first time to this forum, so please forgive my newbie mentality if asking some rather easy questions for you experienced posters.I recently purchased a 17' Bayliner with a 87' 85hp Force engine (3 cyl 2 stroke). The boat hasn't been used yet this year, so its been in need of some maintenance. I know a little about boats from what I've learned from my father and brothers, but I'm not an expert or anything.I've already done the usual cleanup of the trailer, boat (hull, interior, exterior), electrical, charging the battery and now I'm onto the motor. I've already cleaned the plugs and since I don't know the last time it was done, I'm looking at replacing the impeller and changing out the lower unit oil. I've got a manual on backorder but I'm wondering, what are the steps for changing out the lower unit oil? (Is it simply a case of removing the bottom plug, and refilling with fresh oil)? And for the impeller, whats the easiest way to change it out (do the impeller kits from here at iboat come with instructions)? I know my manual should explain this, but I'm eager to keep working on it.Also, while doing an inspection last night, I noticed a slight crack along the fin section of the lower unit housing (the area that you would mount a plane stabilizer). I don't know if its in an area that s/b a concern or not. Will using something like liquid nails or some other adhesive be ok to seal the crack, or is welding in order?Finally, any other mechanical concerns I s/b aware of before putting her in the water?Any help on these questions would be greatly appreciated!
Welcome to iboats! Changing lower unit oil is as easy as you think. First, buy a small hand pump made for changing outboard lower unit oil. REmove the top and bottom plugs and allow the old lube to drain. Note if it has a cloudy or milky appearance which indicates water is leaking into the unit. To refill, leave top plug out and screw the hand pump nozzle into the lower drain hole. Pump in new lube until it begins to seep out the upper hole. Reinstall the upper plug, remove the pump and reinstall the lower plug. Changing the impeller will require you to drop the entire lower unit. Might want to wait on your manual for that. Finally, how bad is the crack? if it is in the horizontal fin (cavitation place) and not too bad, you might get by with cleaning the area and putting a good bead of JB Weld on it. A good photo posted on here would help us give you some advice. Keep posting any other questions you might have.
I know everyone says to fill from the bottom hole then tighten screws but why are the two screws labeled "Fill" and "Vent"?To Change the lower unit lube make sure you buy two(2) seals for those screws. Get some marine gear lube 80w90 or synthetic stuff is good. You need about 26 oz.Lower the engine till the unit is 90 to the boat and flat to the ground with the anti ventalation plate. >>>>>IMPORTANT<<<<&l t;Remove the screw on the bottom not the side! This is a Hex screw! >>>>>IMPORTANT<<<<&l t;Open both top screws as labelled above and replace the gaskets.When draining use at least a quart dish and look at the oil for cloudyness and test the bottom for grit.I let mine drain for 1 hour.Put the hex plug into the bottom and from the fill hole. I fill it from the top Fill hole till it comes out of the vent hole. I wait 10 more minutes and try to fill the Fill hole again.I then wipe off the ecess and put both top screws back in for another season.
Welcome spartan, on filling the l/u with lube, i have always done it docdoc's way, though realgun's sounds good too. the impeller is easy, if you are mechanically inclined. i just changed mine this weekend in under an hour which would have gone much quicker had i the second man recommended in other posts. i ordered impeller, and gaskets from another source as i had a great deal of trouble getting the correct parts due to i guess a split in '89 85hp design. mine came without directions-refer to manual or do search for "impeller replacement" for force forums. as for your crack the obvious answer is that welding the the crack is the most durable/reliable repair. if you have welding experience you could perform the task yourself or look into alumaloy rods which can be used with propane torch. only recommend this if you have experience with fabrication. if you choose to go the jb weld route i would recommend grinding a vee into the crack to give the jb something to properly adhere to, but cannot say on durability of repair. sorry so long-winded
Thanks for the info everybody! Last night I drained the lower unit oil into a small bucket. As it was coming out I noticed the color was dark green-black with little pieces of white/yellow gunk floating along with it. Do the pieces of gunk indicate a bad seal somewhere, or is it possible this just hasn't been drained in a while?As for the impeller, I should be getting a few manuals in the mail this weekend to help with the step by step process. My first question of course is the obvious one, how do I drop the lower unit? Is it the 6 hex bolts in the underside? Do I need to remove the prop first to remove the L/U, or does the whole L/U come out in one piece?I looked at the crack again last night and it runs horizontal along the fin crease. The guy before me had a stabilizing plastic plane-fin (Stingray?) attached to the 4 bolt holes, and it cracked right along the ridge. When I drop the L/U, I'll reexamine the crack from the inside out (looking for light), and try to either weld or use adhesive/sealant.Right now I'm looking at this order: lowering the L/U, replacing the impeller, fixing the crack, reinstalling the L/U, and refilling with L/U oil. Hopefully everything will work well when done.Thanks again..!
I'm a CPA by trade, I like to think I know my way around a wrench, but in reality I know just enough to be dangerous. This process is not too hard. Just take your time.You have the six bolts on the bottom, plus one hidden under the exhaust port. Prop can stay on. Be very very careful when taking the bolts off. If they've been in a while they may be difficult to remove. I dropped my L/U in May and I came very close to twisting a couple of heads off. Before you put the bolts back in, inspect them to make sure they are not twisted or bent. I bent a couple getting them out. If you have bent them you will need to get new ones. The bolts are 3 1/4" long by 5/16 stainless. No hardware store had them, I ended up buying them from a fastener supply company. .97 each. Mercury wanted $3.38 each for the same bolts. All I can say is not to use air tools to break the bolts loose, either on the water pump housing or L/U, they'll twist right off. Go slow and carefully. I twisted one of the bolts off on the water pump housing with a hand ratchet. You will need a second set of hands getting the L/U back up in the leg. Makes things a lot easier getting it back together.
red neck...thanks for the info. I saw the six bolts, and even the bolt under the exhaust snout. Is it possible to get that exhaust snout bolt with a socket? It looks like a tight squeeze.btw: I'm in the same industry as you...and take grief for it at times. Thats why I state I'm a soccer coach by profession, and an Accountant to pay the bills! LOL!
A question about which hole to remove the L/U oil from. Realgun stated to remove the screw on the very bottom, not the lower side. Yet others have stated to remove the screw on the lower side, not the very bottom.Last night I removed the screw on the side. It was a flat edge screw that had a long thinner rod at the end of it. Was that wrong? The screw on the very bottom of the L/U looked like an allen wrench screw and quite a bit smaller. Was that the one I should have used? I was able to get the screw on the side back in without a problem but I'd like to know if its the wrong one for future reference.*Note: I just re-read the schematic from the Mercruiser parts and they list the side screw as the pin/gear shift arm... and the other very bottom screw they list as the plug, gear housing.So should I consider myself fortunate I got the pin/gear shift arm back in...or did I just screw up something new now...yikes!And...does that mean that I should refill from the very, very bottom (using a pump like doc & monkey suggested)...or...fill from the fill screw opening up on the side as realgun suggested?
The screw on the side=bad. Consider yourself extrememly fortunate. You should have bought a lotto ticket too. Don't jack with that one at all. The one to drain is on the bottom of the L/U. towards the front. The one on the side holds some of the internal mechanism together. My L/U has two screws near the top of it that say vent and fill. The drain plug looks similar to that but is on the bottom. Make sure you get new gaskets to put in around the drain/vent/fill screws. Sometimes the old gaskets don't come out. They are in there, you may have to dig them out a bit. DO NOT put a new gasket in without getting the old out. The exhaust snout has an allen bolt that holds it on.I take lots of grief for being an accountant, until tax time when family/friends want help...Just remember there is a fine line between serial killers and auditors.
The more I hear about the screw on the side, the more its sounding I was lucky to get it back in without a problem. (It may explain why it took forever for that stuff to drain out too.) I'll look at the bottom screw tonight as theres probably old oil left at the very bottom that didn't drain out the side.I was wondering about that exhaust snout bolt. I'm going to try and drop the L/U tonight. I have parts on order and can take a look around till they come. ...Luckily, the only taxes I do are the ones for our family... but its funny how everyone still asks for help.