Bravo one leaking at input shaft...
 

Hey guru's of out drives. I have a 1988 bravo 1 and we pulled it for winter storage and noticed there was gear lube in the drive shaft bellow. Im guessing the seal around that imput shaft is bad? How hard is this to change? Is this something I could change?? I have a fair amount of mechanical experience just not on outdrives. Do you think its just the seal or more? And what do you think it should cost if I take it to a shop. Any recomendations in the Detroit metro area? Thanks Oso

My quess is the seal but u don't know untill apart.
It could be that the inputshaft (yoke) is scratchedand where it runs on the seal it needs a sleeve or new !

Click,
Depending on how many hours are on the drive and how old the seal is, I would guess it is just a seal. That is the normal source of that type of leak. Although there is an Oring just inside the snout, which is behind the retainer nut.

You can do it yourself, but there are a few tools you will need. The daisy flower wrench to get that retainer nut off. Then sometimes the input shaft doesnt like to come out. Then you need to remove the yoke and press out the seal and reinstall it, then you have to set the preload on the bearings and red locktite the nut. If when you set the preload on the bearings it doesnt roll smoothly, then they should be replace. And if the thrust washer has been spinning, most likely, the metal from it goes through the bearings and wears them out. That thrust washer is a source of the fine pencil lead goop you find on the magnets.
So yes it can be done, but you need to have the tools and what to look for. If that drive has 500 or more hours, it is time to go through it anyway.
The surface the seal rides on on the yoke can be polished, but if the groove is deep, then it would need a sleeve. I have done that before, but normally a polish with 600 wet/dry cleans it up. If the new seal fits on tight, it should be ok, and the surface is smooth..

Hope this helps.
Dick

I am into this right now I replaced the seal and the o-ring but when it comes to setting the bearing preload I am kind of confused, when I removed the nut it really wasn't very tight really not mcu more than finger tight. How do I know if I have the preload set right?

Something to watch out for on Bravo yoke seal. If you are not using the Merc tool to install seal. The seal sits down a little below carrier assembly, if you install it flush with carrier the yoke will cut into it. Check here and the other site someone posted a link to Merc service manuals. An easy way to hold bearing assby. while doing pre load is to slip the hole assby. back into case and tighten pinion nut through rear cover. Don't tighten carrier nut have the whole assby. lose in case, you are just using case as a holder while setting pinion bearing pre load. Only tighten pinion nut 1/16 turn at at a time after all the bearing start to get a little load on them. Use a big screw driver to hold u-joint while you thighed pinion nut. Keep checking rolling torque (pre load). Use oil don't do it dry. As you get per load if the in lb torque wrench meter is jumping around ( bearing has rough spots) the bearings are bad and need to be replaced. When your done the torque wrench meter should be a smooth reading no jumping. Hope I didn't confuse you.

O YEA the nut isn't that tight USE A NEW NUT & loc tite

I have mine apart I didn't remove the cone clutch or the shift brackets I see in the manual about putting it back into the case and setting the pre-load but that requires removal of the other parts, which I really don't want to do. Is there another way?

Pre load is on the bearings on pinion gear you removed to put new yoke seal in. Kinda hard to explain you need to move the outer bearing off pinion a little and than start tighting pinion nut for bearing pre load. Also on gears still in case you must line up timing marks when you put pinion back in case. + over - or vise versa. lined up with the timing lines in case. If you didn't take the other gears out of case, use the spanner wrench in a vise to hold pinion assby. while setting pre load. put a hose clamp around bearing races while setting pre load so everything will be straight to slid back into case. It is a lot easyer than it sounds. Look at service manaul 11 or 28 there are lots of pictures of what I'am trying to explain.

When I looked into the case I see a + facing me on the top part of the cone clutch. There is nothing on the bottom part that I can see.

OK I have the +/- lined up as close as possible to the back side of the drive marks. It is not perfect aligned but close

so i definitely need a torque wrench with a dial indicator,correct

Yes get one with range of 0-75. You need one to do lower units too All out drive work you will using 3in lbs to no more than 20 in lbs. So thats why you want to get the one that only goes up to 75 or 100 they measure in .001 The scale will read 0-75 in each direction. 0 will be center and it will 75 thousands each way

When the input shaft assby. is tighten back in to case the gears will mesh and the +&- will line up perfectly with lines. Turn the shaft a every 180 degrees of the For. & Rev gears the marks will come up and be opposite. OK if you put together with + on top
& - on bottom and turn input shaft the marks will appear again half way around as - on top & + on bottom, keep turning a other 180 and the marks will back were you stated+ on top & - on bottom. If there are off pull input shaft out enough to reline. Its easier than it sounds good luck

Thanks for all your information. By the way it looks I have the +/- lined up right. The book says it will be close and it is. I am going to get a a torque wrench at work tomorrow to set the pre-load. I am pretty sure we would have them in the power plant.

Make sure you check the chart that shows the torque for the carrier retainer nut. Its 200 ft lbs so a 21 inch torque wrench on the merc carrier nut tool is 127 ft lbs. Mearsure your tools than ceck chrat.

I will do that, I saw where it said that in the book, I can't get a hold of the turbine manger yet to take a wrench home, he won't answer his phone

Can you believe they don't have one and they did but threw it away several months ago. I just ordered a precision 0-100in lbs that way I have one, when I called about getting the seal replaced they wanted a bunch of money so I figured I would do it myself. I saw how the shop tighten the spanner nut up when I lost the lower bearing carrier they beat on it with a hammer

Believe it or not thats the way the retainer nut was tighten years ago. The spanner wrench didn't have a place to put a 1/2 drive torque wench. Mine is beat to hell. When they came out with torque specs, I drilled hole in my spanner and welded in an old 1/2 socket so it could be used with torque wench. Starting to show my age now. Now with your new inch lb torque wench you will be able to do TRS's, Bravos lowers and rear ends. Use the new wrench for rolling torque only, by a cheap Craftsman in lb click type for the small bolts in the drives. Remember when spinning the wrench checking bearing pre loads the needle shound have a smooth reading if its jumping around a bearing or bearings are probably bad. Kinda feels like the bearing is sticking

I have this back together and took it for a ride, It shifts perfect and seems to run ok I drove about 7 miles and it seems ok, no noise just don't trust myself since it was my first time. Do think it is ok?