GEAR RATIO

[MSmith3615]

Can anyone tell me the gear ratio of my out drive or at least how I can find out? I was thinking of replacing it. Its a 1985 merc/260. I think it is either 1.50 or 1.47. And is there any other things I should consider will shopping for a new or rebuilt one. Also what type of cost am I looking at?

 

[TilliamWe]

Re: GEAR RATIO

The ratio should be on one of the sticker on the upper gear housing, port side I believe. But it will almost certainly be a 1.5 (maybe a 1.47 if it's been replaced)<br /><br />Why are thinking about replacing it? Is it broken?

 

[MSmith3615]

Re: GEAR RATIO

I not really sure having some sort of water intrusion around gimbal housing.

 

[MSmith3615]

Re: GEAR RATIO

All the stickers are gone it is the original drive. Read my post from Aug 13-Please Help,Experts needed. That will explain the problem I'm having and after 2300$ and two months I've given in. I figured a new or rebuilt one would solve everything, even though other than water intrusion getting in the bilge after I had the drive pulled, the outdrive is preforming great.

 

[Bondo]

Re: GEAR RATIO

Changing the actual Outdrive will have Little or Nothing to do with Water Intrusion to the Bilge......

 

[MSmith3615]

Re: GEAR RATIO

Well your probally right but I can't seem to figure out why water in coming in through or around the outdrive, unless it is because my transom is rotted and when I pulled the drive and put it back on maybe it made it leak around the bolts? Everything in outdrive is ok. Filled bilge and no water comes out the back or outdrive,just when in water it comes in very very very slowly. How do I know if it is rotted?

 

[bigbrownbuku]

Re: GEAR RATIO

it could be y pipe corrosion. you can usually get your hand in to feel the area the exhaust exits at the bottom of the transom under the motor. next time you dip your boat feel around in that area. or use a mirror and a flashlight.

 

[rodbolt]

Re: GEAR RATIO

if you filled the bilge to the level of the drive shaft your gimbal bearing, ujoints and most likly input yoke is trash. pull the drive again and check for water in the drive bellows. while your there make sure the quad ring in the housing bore was sealed as well as the upper shift shaft seals. replace the gaskets and quad ring seals on reassembly after testing/replacing any water damaged bearings. water intrusion is normally a drive bellows or shift cable bellows. to test the transom trim the drive level and have someone bounce up and down on the aft ednd of the drive. if the transom flex's its over it. but do check for water in the drive bellows.<br />the damage that ujoints coming apart or a gimbal bearing that siezes can be catastrophic to both drive and transom shield. the damage a rusty input yoke can have is catastrophic to the upper and usually gives absolutly no warning. your just zipping along all tricked out and happy and whammo no drive-o.

 

[MSmith3615]

Re: GEAR RATIO

Wow Rodbolt you really know your stuff, well when I had the drive off was to replace yoke seal,for sure water is not in bellows, water is not getting in the outdrive. I do think you pointed to problem, raised trim up to level and pushed on drive. FLEXED REAL BAD. When I had yoke seal fixed did all that other stuff with merc tech. I should have noticed it when drive was off, my friend who runs a boat shop thats been around since the 40's did not mention anything either.

 

[MSmith3615]

Re: GEAR RATIO

I'm never going to get this boat really done, I've spent almost two years and everything is pretty much new except engine and outdrive, and know I have a bad transom. That is the first thing I should have checked for, boy I feel dumb. Fixing the transom is out of my league, my friend will do it if I help him but I WILL have to pay. Can I at least wait until fall or winter? I just got it back in water and its running so good. How due I tell how bad it is?

 

[MSmith3615]

Re: GEAR RATIO

I will take pic of were water is coming in, or maybe I don't need too it transom is rotted.

 

[rbezdon]

Re: GEAR RATIO

You are right, rod is one of the best. I think Rods point was that if you filled the bilge to try to check for water leaking out of the boat and you filled the level up to the drive bellows, you will have gotten water into your new yolk from the INSIDE of the boat. If any water got in from the inside, it is still in there unless you pull the drive again. The drive train is not protected from water intruding from the inside as it is not an expected condition. Other than this being a concern there is also the possibility the torque from a good run or hard start stop loosening the transom worse and giving you a much bigger leak quick. Sure hope you dont pull shiers and tubes and take off full throttle.

 

[MSmith3615]

Re: GEAR RATIO

Now I'm worried I filled the bilge up to where I thought I saw the water coming in, I don't know very much but I do know not to fill it up too the drive bellows. I just pulled skiers and tubes two day ago. The 260 merc has alot of torgue in my 21ft cuddy should I even run the boat? Are you saying it might just fall off?

 

[MSmith3615]

Re: GEAR RATIO

Any info on transom repair and cost please.

 

[rbezdon]

Re: GEAR RATIO

I dont know, I am not an outdrive expert so I hope some of the more drive experienced guys will answer but I would think if the transom flexes as much as you said above that it would be more likely the torque of take off pulling a big load could make something flex the same way and cause a shift or crack which would leak faster. I didnt mean to scare you but it seems logical if a 180 pound guy can flex a transom, a 600 lb 260 HP V8 could do it more and that cant be a good thing with a weak transom. I hope some one else has some experience with a bad transom for you. Maybe you can post for the transom repair on the restoring forum as well.

 

[Haut Medoc]

Re: GEAR RATIO

3615 = Harry?

 

[MSmith3615]

Re: GEAR RATIO

Thank you vatter41. I don't know what to do, Oh ya thanks J.kopec you seem so helpful. Maybe your outdrive will fall off, I hope mine doesn't with my wife in kids in the boat, well maybe not. Remember this forum is supposed to help people not make fun off them. And vatter41 I wish I still weighed 180. I'm going to post another topic about replacing transom. Hopefully I will get some help.