Installing Merc #3 Drives - HELP
 

I'm trying to Install #3 drives and having major difficulties. Is there a trick in getting the yoke to line up and through the gimble bearing. The shaft is short and it makes it difficult to guide the yoke in because the drive gets close to the bell housing and you you have to get your hands out of there. The fit between the belhousing opening and the u-joint carrier is tight too. The engine alignment seems OK. I've spent a good 2 hours trying to get one drive on. Any suggestions would be greatly appreciated.

Re: Installing Merc #3 Drives - HELP
 

There should be a spring on the end of the female spline in the boat, but that only helps a little bit.

Try and reach in with a long skinny screw driver. Then you play with the height & angle of the drive.

Re: Installing Merc #3 Drives - HELP
 

I don't think there is a spring. The tough part is getting the shaft to the opening of the gimble bearing. I tried the screwdriver for a while. Guess I'll try again. This sounds stupid but I've also thought about sliding the engine forward, tying a small string around the shaft and trying to pull it through.

Re: Installing Merc #3 Drives - HELP
 

I helped my buddy a couple times,I know it's a *****.

Re: Installing Merc #3 Drives - HELP
 

I assume you're talking SSM III.
I've wrapped the U joint with masking tape to keep it in a strait line. It sheads to pieces very quickly and doesnt seem to hurt anything. Makes installation a breeze.

Re: Installing Merc #3 Drives - HELP
 

That's what we do Gary, it really works.

Re: Installing Merc #3 Drives - HELP
 

I'll give the masking tape a try!!!!!!!!!!!!

Re: Installing Merc #3 Drives - HELP
 

After many failed attempts, I did it in about a minute once I figured this trick out.

It helps to rotate the input assembly so that the front U-joint is lined up a certain way. This will help you guide the splined shaft in without relying on luck. This is from memory late at night so I'll try my best- First off:

from front to rear of the input assembly there is:
A splined shaft with 2 ears
A front u-joint
An intermediate coupling with 2 ears on each end
A rear U-jount
the drive input shaft with 2 ears

A U joint has 4 trunnions which fit into the ears and are held in by the cups/clips

The splined shaft has 2 ears which fit onto 2 U joint trunnions. The trick is to rotate the shaft so that these ears and trunnions are lined up vertical (up and down). This prevents the input shaft from moving up/down on this axis- it can only rotate side to side.

The other 2 ears and trunnions of the front u-joint are on the intermediate coupling and will be horizontal. These will allow up/down movement.

Push the drive in until the splined shaft stops it, then back off slightly. The splined shaft will be hanging at an angle, downward inside the transom assembly. To align the shaft, you can then move the splined shaft up/down by pushing on it with a coat hanger from the rear.

Good Luck

Re: Installing Merc #3 Drives - HELP
 

you brought back horrible memories of the first time i installed a speedy, before anyone told me about the tape trick, that sucked and the tape does work. Trs's can be a pain too.

Re: Installing Merc #3 Drives - HELP
 

Whew, I thought I was going to get flamed for suggesting masking tape.