Engine coupler replacement

[TBarCYa]

Is there a how-to anywhere about how to replace the engine coupler on my Mercruiser 888? I know the engine has to be lifted and turned to gain access but does anyone have any suggestions or tips on how to make the job easier? I would rather leave this job to a mechanic but this is the 2nd day of my vacation and local mechanics wouldn't be able to have it done until next week.

I'm thinking that I will rent an engine hoist and assemble it in the boat with 2x6 planks spanning the stringers and the hoist sitting on the planks. This should allow me to get the engine out of the way but if there is a way that doesn't involve hauling a heavy piece of equipment into the boat that would be very helpful.

Thanks.

 

[Haut Medoc]

Re: Engine coupler replacement

Nope, the engine has to be moved.....
Enough that you can get behind it to work.....

I would also find out why the coupler failed.....
Poor alignment can be from transom issues or bad rear motor mounts.....
I suggest you check the alignment before you pull the engine, to see where you are at with regards to alignment, if your alignment is bad & you just throw a new coupler at it, it too, will fail prematurely........​

 

[TBarCYa]

Re: Engine coupler replacement

When I installed the replacement drive about a month ago I used the old driveshaft to verify that the alignment was good after replacing the gimbal bearing and it went right in. I then installed the drive and it went in without a hitch so I believe that the alignment is good. On Sunday I was out in the boat and got into some shallow water and the prop was in the mud. I'm sure that it wasn't the first time the drive was in the mud so it probably failed due to stress.

There is lots of room behind the engine for me to work but it looks like the bellhousing has to be removed to get to the crankshaft. Is this true?

Is the Mercruiser manual online for the 888 engine/drive?

 

[Haut Medoc]

Re: Engine coupler replacement

When I installed the replacement drive about a month ago I used the old driveshaft to verify that the alignment was good after replacing the gimbal bearing and it went right in. I then installed the drive and it went in without a hitch so I believe that the alignment is good. On Sunday I was out in the boat and got into some shallow water and the prop was in the mud. I'm sure that it wasn't the first time the drive was in the mud so it probably failed due to stress.

There is lots of room behind the engine for me to work but it looks like the bellhousing has to be removed to get to the crankshaft. Is this true?
Yes, there is no way around it....
& the bell housing sits on the inner transom plate mounts.....

Is the Mercruiser manual online for the 888 engine/drive?

No, not online....
You need Manual #1 or #2 will do as well.....

 

[TBarCYa]

Re: Engine coupler replacement

That sounds good. Thanks.

 

[xltier]

Re: Engine coupler replacement

i changed one on a sea ray 19 ft. once without pulling the motor.didnt have a trailer available so we put a bottle jack under the oil pan and took the bell housing off and changed it that way.if you got room and dont have a hoist its a thought.

 

[TBarCYa]

Re: Engine coupler replacement

I've been reading a bit about coupler failures and most people seem to strip the splines rather than my situation where it appears that the rubber has failed. Is this consistent with age/abuse failure rather than failure caused by improper alignment?

 

[TBarCYa]

Re: Engine coupler replacement

i changed one on a sea ray 19 ft. once without pulling the motor.didnt have a trailer available so we put a bottle jack under the oil pan and took the bell housing off and changed it that way.if you got room and dont have a hoist its a thought.

I had thought about doing that but how much does the engine need to tilt to get the bellhousing off? It looks like most of the bellhousing is below the rear mounts so it would basically have to stand on it's nose. Do the front mounts get removed or can it pivot around those mounts?

 

[erikgreen]

Re: Engine coupler replacement

Nope, those mounts either need to be removed from the wood they're lag bolted into, or they need to be unbolted from the engine.

To remove the motor coupler you'll need to remove the bell housing, and as others have mentioned you may need to check and replace the rear motor mounts - if they're not holding the alignment, you'll just be sacrificing another coupler.

I know this isn't something you want to hear, but there isn't a quick way to do this... it's actually harder (and more dangerous) to try and do it the "quick" way as you describe than to do it the right way... which means you need to completely remove the engine from the boat long enough to take the old coupler off and bolt the new one on. I wouldn't even try to do this using a motor hoist in the boat, you won't be able to move the motor around far enough, and you risk damaging your deck and banging the motor against fiberglass.

If you can't get a gantry hoist or large motor hoist to get the motor out of the boat, try a towtruck - a decent sized one could lift the motor out, or a forklift could. Maybe you can rent one of these, or even rent a 10 foot motor hoist to get the engine out of the hull.

If you can't get any of those and your choice is to do it inside the hull or go without your boat, I really recommend you go without your boat. Maybe rent a boat?

Sucks, I know, but there isn't an easy fix for this. My 888 took me 2 hours with the help of 2 friends to get out of my 22 footer the first time I did it.

Erik

 

[alaska_av8r]

Re: Engine coupler replacement

I just finished up putting a new motor in a searay 888. Rent an engine hoist from a tool rental place and the job will be as smooth as it can get. They have them that hook right up to your trailer hitch. One person can remove it but you will need at a minimum of two to put it back in without breaking something.

 

[wire2]

Re: Engine coupler replacement

I hit on a different way that might be worth describing. Boat was stored in a garage with exposed roof trusses. I placed a length of 4 x 4 across 4 of them to spread the weight, put a short nylon sling around the middle & hung a ? ton come-along on it. Lifted the 5.7 straight up, rolled the trailer back 3 ft to have the engine clear on all sides to work on it.

 

[freddyray21]

Re: Engine coupler replacement

I've pulled two motors using my garage rafters. (double 2x10's) but both were 4 cylinders and I question the wisdom now. I got lucky the last motor I did for a friend. He was a wrecker driver. No problem with a wrecker, but it can get expensive if you have to pay for it.

 

[TBarCYa]

Re: Engine coupler replacement

Thanks for all of the responses. We've decided not to try fixing it for the rest of the week and to wait until we get home. My engine hoist isn't tall enough to pick from the ground as the transom is about 6' high when on the trailer. I don't really have a place to work on the boat where I could use a forklift so I'll have to see what other options are out there. I don't know if any of the local rental places have a 10' hoist but I guess I'll call around and find out.

Thanks again.