Rear Motor Mount Bolt/gimbal bearing**UPDATE**

[jmanjeeper]

Good afternoon!

I have an issue, and being a new boat owner, I figured this was the best place to ask my questions....Before I being, I am very mechanically inclined when it come to vehicles, never worked on a boat but I'm confident I can fix just about anything vice opening up the motor.

My boat is a 1992 Starcraft 191 Eurostar F/s with a 220hp MPFI Mercruiser and an alpha one lower unit with a 21 pitch stainless Prop.

1. the starboard side bolt on the rear motor mount was out.....I can push it all the way in and out, is there supposed to be a nut on the bottom or is it stripped? How do I fix it????

2. The motor runs great! Cranks up first time right away....but if I throttle up in neutral, there is a knocking noise coming from behind the motor....I did a little searching and found that it may be the bearing around the drive shaft that mates the lower unit to the boat...if so how hard is this to change? or how much would it cost for me to get it done?

Thanks in advance!!

J

 

[Reel Poor]

Re: Rear Motor Mount Bolt/gimble bearing

Re: Rear Motor Mount Bolt/gimble bearing

There should be a nut that slides into a slot (slot runs front to rear under the boss the flywheel housing sits on) on the transom plate. The slot holds the nut in place, keeps it from turning and falling out when the bolt is removed.

If your referring to the Gimbal Bearing see section 4 sub category A in the link below.

http://www.boatfix.com/merc/Servmanl/6/6covr3.pdf

 

[jmanjeeper]

Re: Rear Motor Mount Bolt/gimble bearing

Re: Rear Motor Mount Bolt/gimble bearing

Thanks!

I think I can handle the Gimbal bearing if I can locate the proper tools...

Also, looks like the nut may have come out that is supposed to hold that bolt in, and it's probably somewhere in the bilge, or lost forever, lol. I'll take a closer look when I get home from work today and see what I need to do.

Thanks again for the information!

 

[jmanjeeper]

Re: Rear Motor Mount Bolt/gimble bearing

Re: Rear Motor Mount Bolt/gimble bearing

well I ended up not having to work today, so I went out and took a closer look. Good news the nut is in fact missing, now the next Newb question....

Can I just go to the hardware store and purchase a nut that will fit the bolt, or is it a certain nut needed to fit in the sleeve?

 

[Reel Poor]

Re: Rear Motor Mount Bolt/gimbal bearing

Re: Rear Motor Mount Bolt/gimbal bearing

It's a standard nut. Be sure to get a stainless steel nylock nut.

 

[MercMonster]

Re: Rear Motor Mount Bolt/gimbal bearing

Re: Rear Motor Mount Bolt/gimbal bearing

I think I can handle the Gimbal bearing if I can locate the proper tools...

If you have an auto zone near you, they have a loaner tool program where you pay, use the tool, then bring it back and get your money back. Most of them should carry the puller you need to remove your gimbal bearing. Three easy pulls and the gimbal bearing popped right out.

 

[jmanjeeper]

Re: Rear Motor Mount Bolt/gimbal bearing

Re: Rear Motor Mount Bolt/gimbal bearing

OK, so i bought a nylock nut....HOW DOES IT GO IN THERE???? I just spent 15 mins trying to get my huge mits down in the hole only to drop the nut into the bottomless pit under the motor! I felt around and can feel where the nut goes from the other mount, but how do I get it into the slot and into position for the bolt??? Do I need to loosen the other mount and pick up the mount to drop the new bolt in? Please help, I think I just lost 20lbs of water weight in the lovely Florida heat wave!

 

[Bondo]

Re: Rear Motor Mount Bolt/gimbal bearing

Re: Rear Motor Mount Bolt/gimbal bearing

but how do I get it into the slot and into position for the bolt???

Ayuh,........

I usually Tape them in place Before the motor is installed.......
And,.........
It just Might be Impossible,..... to Do what you Gotta Do............

 

[jmanjeeper]

Re: Rear Motor Mount Bolt/gimbal bearing

Re: Rear Motor Mount Bolt/gimbal bearing

So they drop in from the top then? Because from feeling around, I cannot see how the hell they would be able to fit into the place they should be....hopefully it will cool down a little tomorrow, or I may just haul the boat to the auto hobby shop and work in the shade/fan with a hoist on base... thanks!!

 

[Bondo]

Re: Rear Motor Mount Bolt/gimbal bearing

Re: Rear Motor Mount Bolt/gimbal bearing

So they drop in from the top then?

Nope,...... They slide in from Fore to Aft.......

 

[jmanjeeper]

Re: Rear Motor Mount Bolt/gimbal bearing

Re: Rear Motor Mount Bolt/gimbal bearing

Thanks, Ill get another couple of nuts and have a go at it tomorrow. Maybe Ill get my wife to help out, she may be able to get her little hands in there.

Thanks again! Lord knows with an 8mth old daughter I can't pay a shop to fix anything, lol.

 

[Bondo]

Re: Rear Motor Mount Bolt/gimbal bearing

Re: Rear Motor Mount Bolt/gimbal bearing

Been in the Navy 10yrs and loving it!

Our Advise is a small price to pay,.... To keep a Sailor from Swimming.........


Thank You for your years of service to Our Country.................

 

[jmanjeeper]

Re: Rear Motor Mount Bolt/gimbal bearing**UPDATE**

Well, I fixed her up yesterday. I pulled all the enclosures off the motor...took 3 minutes, I was able to clean out the bilge, which I found a wrench, 6 stainless screws and the original nut that was missing from the motor mount. I have to say it was a HELL OF a lot easier to get the nut in with the surroundings off! I slid the nut in, tightened the bolt down, and once again cooking with Crisco!

The Gimbal bearing was also fixed, So now I am going to throw her in the water and see how she does. thanks for all the help!!!

 

[rodbolt]

Re: Rear Motor Mount Bolt/gimbal bearing**UPDATE**

take it from a fellow sailor.
dont be in such a rush.
its much cheaper to test and repair first and boat later.
if you dont know the maint history then a seawater pump,gearlube change and gimbal/ujoint bearing checks are in order BEFORE it comes unwound.
I just condemed the 5.7 in a 2001 grady. guy bought it in june,ran it,seawater pump failed 2 weeks ago and he is out a motor.
he doesnt have the 11K to replace it so its out of action now.
over a 45 dollar pump kit.
so trust me, if you dont have the maint records assume its not been done and catch up on it. the base hobby shop will have most tools you need other than the shaft alignment tool.
DonS can post whatever manuals you need and the rest of us can talk ya through it.
good luck
Rodbolt FC2 RET.