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Special Tools for Replacing Alpha Gen II Gimbal Bearing

Removal and installation of your Gimbal Bearing requires a few special tools.
Attempting to remove and/or install the bearing without the special tools can
damage the gimbal or bearing.
The special tools make the job MUCH easier.

91-34569A1 Slide Hammer Puller Kit $ 164.00
Used to remove the gimbal bearing
91-32325T Bearing Driver $ 38.12
Used with two other tools to drive in the new bearing
91-30366T1 Installer Head $ 32.00
Used with two other tools to drive in the new bearing
91-37323 Driver Rod $13.00
Used with two other tools to drive in the new bearing
91-805475A1 Alignment Tool $152.00
Used to line up the newly installed bearing and engine.
This tool makes it easier to install the drive after the bearing has been replaced.
Engline alignment should be checked every season.
30-862540A3 Gimbal Bearing $105.00
Fits R, MR, MCI, Alpha One, Alpha Gen II and Standard Bravos
27-94996Q2 Gasket Set $9.00
For mounting the drive. Includes o-rings.
Fits Alpha One and Alpha Gen II
27-64818Q4 Gasket Set $9.00
For mounting the drive. Includes o-rings.
Fits older crowned-type drives such as Model 165, 888 and R drives.
92-86166Q1 Bellows Adheasive $ 10.00
Used to glue bellows and orings into place.
92-802870A1 Universal Joint and Gimbal Bearing Grease
Used to grease the gimbal bearing and ujoints $15.00


You do not have to remove the Bellhousing or Ujoint Bellows to replace the Gimbal Bearing.
However, the bearing usually fails because the bellows have leaked.
If you have evidence of water in the bellows they should be replaced while replacing the gimbal bearing.

You have to remove the drive to access the gimbal bearing.
Place the remote control shifter into forward gear before attempting to unbolt and remove the drive.
(Counter-rotation LH drives must be shifted into reverse gear before being removed).

IMPORTANT: Remove the battery negative cable as so the engine will not start or crank.
It the engine starts damage, injury or death can result from moving parts and/or propellars.

Remove the two trim cylinders from the drive and let them hang out of the way.

Remove the six drive mounting bolts and try to pull the drive off.

WARNING: The drive is heavy. Use care to prevent injury. It is best to have two people as
the weight of the drive can injure you once it breaks loose.

If the drive does not pull off easily it might be stuck.
Lift the tail end of the drive a few inches and let it drop freely.
This "jarring" will usually break the drive free from the bellhousing.
The process might have to be repeated or exagerated a few times until the unit breaks free.

Once free, the drive should pull right off but remember to use care as it is heavy and you can damage your back.

Set the drive out of the way and inspect the gimbal.
Check for any cracks, water intrusion, wear, corrosion and/or free-play.
Plan your repair by making sure you list ALL the parts required for a complete repair.

Assemble your slide hammer as so you have the three-jaw puller installed and that
the three jaws are facing outward.
Slip the tips of the jaws in through the center of the gimbal bearing and expand the jaws
as far as possible as so they firmly lock into place.
NOTE: You will thread the jaw-lock-ring down towards the jaws to make them lock outward.
It is important that you lock this ring down into place as tightly as possible.
After you slide hammer a few times you might have to re-tighten the ring-nut again.
Failure to keep the jaws fully expanded will result in the tips of the jaws snapping off.

Use the slide hammer with a firm slamming force to pull the bearing out.
This may not be too easy! Be patient and keep slamming.
If it just won't slide out you have a problem.
SOMEHOW you HAVE to get that bearing out.
We know of a few tricks so just send us an email and we will help.

When the bearing comes out you will notice that it also pulled with it it's aluminum shell and stainless tolerance ring.
The new bearing will include all these parts.

You must spend a little time and effort to prepare the hole for the new bearing.
Use a clean rag and wipe out any grease or goo.
Use your fingers and feel around the inside perimeter of the hole where the bearing seats.
You must not be able to feel any and ridges but if you do you can use some 200-250 grt sand paper and
gently sand inside the hole evenly all around to remove any corrosion build-up or hardened grease residue.

Notice that there is a seal located in front of where the bearing was located.
This is primarily designed to keep grease from the bearing from splattering around
inside the engine compartment. If it looks bad you can rip it out and install a new one.
In most cases you will not have to replace this seal.

Clean out the bellows and seating area. Smear a thin coating of Universal Joint and Gimbal Bearing Grease
onto the surface areas where the bearing will be installed to aid in it sliding into place.

The new bearing must be prepared for installation.
Slide the outer stainless tolerance ring around the bearing shell until the grease passage hole is visable.
Use a marker and mark the location of the hole on the side of the shell.
This hole must line up with the hole in the gimbal housing.
Smear a thin coating of Universal Joint and Gimbal Bearing Grease around the perimeter of the bearing.

NOTE: Some customers like to freeze the bearing before installing. This might really help!

Get your installation tools ready.
Thread the head tool onto the end of your threaded driver rod.
Slip the Collar tool over this head with the smaller inner rim towards the handle.
It looks funny but it works.

Notice that your new bearing has slots in the aluminum shell.
These slots should be facing towards the bow of the boat when the bearing is being installed.

Slip the bearing onto the end of the tool to see how it fits.
Make sure the slots in the sleeve are forward and take not of the position of the grease hole.

It is best to use a large dead-blow hammer to drive the bearing into place.
Blue Point and Snap-On make good dead-blow hammers.

Position the assembly into the hole making sure the grease-hole mark lines up with the grease passage in the gimbal.
IMPORTANT: It is extremely important that you drive the bearing in straight.
THIS is where most people have a problem.
You MUST start tapping the bearing in PERFECTLY straight or you can ruin the new bearing or
you can ruin your entire gimbal housing assembly.

After a few taps if you think you have it straight, start hammering harder.
Each hit should drive the bearing in further.
If you are hitting the bearing and it's not going in... STOP and inspect for straightness.

If you suspect the bearing has cocked off to one side and it is stuck it must be removed.
NEVER, never, never attempt to straighten the bearing.
Once it's crooked it builds up a metal burr in the bore and this will prevent a full installation.

If you have to remove the bearing, inspect the hole for any burrs.
Feel around in the hole with your fingers.
Use 120-200 sand paper to remove the burr. Finish with 250 grit.

While hammering in your bearing the "hit" will have a certain sound to it.
If the bearing jams, the hit's sound will change a little.
Once the bearing is fully and properly seated the sound of the hit will be more "solid".
The bearing must be fully seated in order to install the drive.

Pump a couple of squirts of Universal Joint and Gimbal Bearing Grease into the zirt grease fitting on the stb side of the gimbal.
Do not over-grease the bearing. Wipe out any excess grease.
Excess grease will get in and ruin the ujoint bellows.

Take your greased engine alignment tool and insert it in through the bearing and into the drive coupler.
At first you might have to tap the tool up or down or left or right before it goes into the coupler.
You might also have to tap the tool all the in the first time.
Once the tool goes in all the way, pull it back out, grease it a little and make sure it slips in place
all the way nice and easily.
If the tool won't turn easily with one hand when fully inserted you might have to adjust your motor mounts to
achieve proper engine alignment.

Clean off all the old gasket material from the bell housing and drive.
The Gasket Kit includes new orings which must be properly installed.
Coat the outer perimeter of the large fat oring with Bellows Adheasive and
install it in the bell housing bore where the drivehshaft passes through.
It must be fully installed up against the rim in the hole.
Once in place, grease the inner oring with Universal Joint and Gimbal Bearing Grease.

Coat the water passage oring with Bellows Adheasive and glue into place on the bellhousing.

Replace the orings on the drivehshaft and grease.

Position the gasket onto the six studs and up against the bellhousing.
DO NOT apply any sealant or silicone adheasive to the gasket.

Use some Universal Joint and Gimbal Bearing Grease or use Mercruisers Coupler Spline Grease on the
splines of the drive yoke.
If neccessary, pump a couple of squirts of Universal Joint and Gimbal Bearing Grease into the cross-bearing
grease zirt fittings.
Gen II Alpha's do not normally have cross-bearing grease fittings.
Do not install a drive if the ujoint cross bearings are bad.

Make sure your shift lever is in place so the roller is in the fork notch and
make sure your shifter is in forward gear.

Make sure your drive unit is in forward gear before installation.
This is done by looking down at the little shift "shoe" and turning it clockwise while turning the prop
in the left hand (counter-clockwise) direction. This will position the "shoe" straight forward and the prop will "lock" into forward gear.
CARE must be taken to make sure the drive stays in forward gear during its installation.
IF you bump the prop by accident it could bump the drive out of forward.
I have seen some techs strap the prop with a bungie chord pulling it in the counter-clockwise direction
as so it stays locked in forward gear.

It is best to have the height of the gimbal at the same height of the drive during installation.
This prevents you from having to lift the drive into place.

Position the drive into place while working the driveshaft through the gimbal bearing.
As you push the drive on you need to be aware of the position of the shift shaft.
If the shaft has come out of gear and cocked off to one side you will have to re-lock the drive back into forward gear.

You also have to take care to make sure the shift lever/roller stays in the fork slot.

The drive might have to be "nudged" up into place until it is fully seated.
Once in place quickly install one locknut to hold it there as so you can take a breather.

In some cases you will have to turn the prop in the REVERSE direction while pushing the drive into place.
This will help line up the driveshaft splines to the coupler splines.

If the drive just won't go on the last 1/2", it's usually because the shift shafts where not straight.
Forcing a drive on while the shift shafts are off will ruin $120 worth of shift shafts not to mention you will
never get the drive fully installed.

Once you have successfully installed the drive and fasted with one locknut, test the shift.
This is best done with two people, one in the boat and one to turn the prop by hand.
Shift into forward and have the prop-person turn the prop. It will rachett in the forward direction and lock in the reverse direction.
Shift into neutral and the prop should spin free in both directions.
Shift into reverse and the prop should rachett in the reverse direction and lock in the forward direction.
If you have trouble shifting you may have installed the drive wrong.

Install the rest of the locknuts and snug them up firmly.
Install the trim cyinders

Use care when water testing the boat for the first time.
Be aware that if the drive was improperly installed that the engine could start in gear thus cuasing damage, injury or death.

Check for smooth shifting and watch your engine opertaing temperature.
Inspect the transom and bilge area for any water leaks and fuel leaks.

If everything looks good go boating and have some fun.

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