View Full Version : Prop shaft mount

04-18-2008, 01:00 PM
Hello, I own a 2002 Moomba Outback, great boat. I am wondering if the inner lining of the Shaft mount, under the boat, ever needs to be replaced? If it does need to be replaced, how do I get the part and what is the tech name for it. Also, can it do any damage to the boat? Any advice will be greatly appreciated..

Thanks Todd

04-18-2008, 01:51 PM
are you referring to the strut bearing/bushing?

if so, yes they will wear out over time. usually quicker due to the shaft being OUT of alinged.

check with either your dealer or skidim.com for the part.

04-18-2008, 04:26 PM
I have wondered this myself. I have always wanted to know how you tell when one has gone bad? What are the conditions that warrant replacement?

04-18-2008, 04:40 PM
jesse, recommeded every 300 hrs. if you feel some back and forth play in the drive shaft it needs to be replaced.

as i stated if the shaft is not alinged correct it can cause them to wear out quicker.

also they can be damaged if prop/shaft make impact with a hard object.

04-18-2008, 04:58 PM
qb12, Thanks for the info I think I just passed 240 hours or so. I may make this a winter project for next year.

04-18-2008, 05:55 PM
how can you tell if its not aligned perfectly?

04-18-2008, 07:03 PM
this is a fun process! HA. I replaced mine last summer when I replaced my bent shaft and prop. You'll have to pull the shaft out completely to replace them... to pullthe shaft, you'll have to pull the rudder off.

Getting the little buggers out is a trick. There is a tool that does it... OR you can use a hack saw. Let me know when you get ready, i'll explain.

Shaft alignment procedures: LONG but good info. Someone named Doug from on here sent them to me last summer

Shaft Alignment Procedure

Completion of this work should take less than 1 hour .

Tools Required:
Phillips Screw driver
2-9/16" wrenches
Torque Wrench
Feeler Gauge Set


Align the Engine coupler to the Shaft coupler with less that .002 gap.

Removing the Interior:
1. Remove the motor box and rear seat.
2. Remove the rear center floor.
3. You should now be able to see the Shaft Coupler/Transmission Coupler Interface.

Removing the Bolts:
1. Locate the Shaft Coupler/Transmission Coupler Interface.
2. You will see four bolts holding the two couplers together.
3. Using two 9/16 wrenches loosen the nuts from the bolts.
Once the bolts are removed check the following:
1. The grade marking on the head of the bolt should read "S30400".
2. They should be a 3/8-24 X 1 -" Stainless Steel bolts.
3. Look for wear or damage.
4. If the bolts are incorrect or are damaged replace them!

4. Once the bolts are out the coupler should naturally want to match up with out any pressure. At this point do a shaft alignment.

Aligning the Engine:

1. Holding the two couplers together, take a feeler gauge set and see if a .005 gauge feeler will slide between the couplers at any point around the circumference. Be sure to run the feeler all the way around. If it will slip between the couplers go to step 2. If it does not slip between the couplers go to step 4.

2. Next, spin the shaft coupler 180 degrees. Holding the two couplers together, again, take a feeler gauge set and see if a .005 gauge feeler will slide between the couplers at any point around the circumference. Be sure to run the feeler all the way around. It should slip between the couplers at the same point as it did in step I, if it does slip in the same spot, go to step three. If it slips between the coupler at a point 180 degrees for where it did last time examine shaft for damage (it may be bent) and examine the coupler for damage. If no damage is found, repeat steps 1 and two.

3. Too close a gap between the couplers the engine will need to be moved slightly.

- If the gap is at the 12 O'clock position you will need to raise the front of the engine or lower the back of the engine. To do this (using the rear feet): loosen the jam nuts on the rear feet. Then put a wrench on the tops and turn it counterclockwise. Make sure to count the turns and turn both the right and left feet equal amounts. This will lower the back of the engine and close the gap. If you went too far you will open a gap at the bottom. When using the rear feet to make adjustments, be sure not to lower or raise the shaft & coupler out of its "natural" position. For major angular movements (were you need to move the engine 2-3 thousand) use the front feet for the majority of the movement, then fine tune with the rear mounts.

- If the Gap is at the 3 O'clock position you will need to slide the front or rear of the engine over. To do this, loosen the nuts on the trunnion pins. Then tap the trunnion pin lightly to back it off and loosen them from the trunnions. This will allow the engine to be moved side to side. Using a pry bar, push the front of the engine more starboard to close the gap. If you push it to you will create a gap at the 9 O'clock position.

- If the gap is between the 1 and 2 0' clock position, you may be able to get the gap closed by lowering the left rear foot only.

- Keep repeating these steps till a 0.005 feeler gauge will not fit between the couplers at any point. Be sure that the shaft remains in the its natural position so that you do not cause premature shaft packing wear or strut bushing wear. Once you have gotten the engine aligned to within 0.005 repeat the above steps until the engine alignment is within 0.002.

1. Make sure to lock down all the jam nuts on the engine feet and the trunnion pins on the trunnions.

2. Recheck the engine alignment after the jam nuts and trunnion pins have been tightened. If it is still within tolerance you may proceed.

Reinstalling the Bolts:

- Install the bolts (3/8-24 x 1 " S30400) through the couplers and install the 3/8-24 Nylock Stainless Nut.
- Torque the bolts to 25-30 Ft Lbs.
- Double check that the jam nuts on the engine and the cotter pins on the trunnions are tight.
- Double check that the shaft coupler bolts are torqued to 25-30 Ft Lbs.

Replacing and Adjusting the Shaft Packing.
- Replace the shaft packing. Be sure to install two or three pieces.
- Loosen the jam nut on the shaft-packing gland.
- Back the gland nut off the packing gland assembly.
- Dig out all the old packing material.
- For a one inch shaft, cut two to three pieces of 1/4"dia. packing material strips so they are 4 1/8". Place one of the packing strips into the packing nut. The end should butt together. Place another piece in the packing nut, this time orienting the seam 180 degrees from the seam of the first piece.
- Slide the packing nut up the shaft.
- Slide the shaft through the Packing gland assembly and into the strut.
- Screw the packing nut onto the packing gland assembly. Tighten it up as much as possible by hand. Then using a wrench, turn the nut a 1/2 a turn forward and a 1/4 turn back. Then turn the nut a 1/2 a turn forward and a 1/4 turn back. Then turn the nut a a turn forward and a 1/4 turn back. This will pack the packing fairly tight.
- Back the packing nut off the assembly again. Then thread it back on. Tighten it only as tight as you can get it using your hands. This should be almost the perfect tightness for the packing gland so that it does not leak, yet not too tight so that the packing burns up.
- Tighten the Lock Nut up to the Packing Gland Nut.

If you want to add the third piece of packing, do so when you back the nut off after you packed the packing. Then tighten the nut only as tight as you can get it using your hands. This should be almost the perfect tightness for the packing gland so that it does not leak, yet not too tight so

04-18-2008, 07:36 PM

that would have been me. this doug :D

got all the info direct from the great "brian raymond".

04-18-2008, 08:02 PM
I could not remember and I was trying to put Doug with a screen name.. HA.. did not fit with QB12.. Good info though! Thanks.

How is T Town? Wet? We have much flooding over here along the Miss river. I go to Vicksburg most every day and rode over by the river yesterday.. It is pretty sad. Worst flood since '73 right now. I ride with a guy some who has a place on Eagle Lake ( old dead river lake off Miss)
Lake is fine and his place is high/dry but can't easily get in and out. He just got a new XStar and had to move to safer ground.. Be a month before the water is down/out...

We plan on riding this weekend. I don't know if you saw the post on Wakeworld about Murray and the Pay it Forward boards. We got the 145 Murray to try out this weekend!!! YEAH

04-19-2008, 08:32 AM
we have had a lot of rain and some damm large hail. being in the insurance bizz, has not been fun this last week.

but heading out to the lake after son's bball tourney. suppose to be 78 with winds of only 3-5mph.

take care.

04-25-2008, 10:29 AM
Thanks you guys for the information. It has helped me out a lot. I guess I can let it go a little longer. My Outback has about 240 hours. After doing a visiual inspection the condition of looks pretty good. Heres another question about it, can the strut be taken off the boat and slid off the shaft, or does th e shaft have to be taken off?

Thanks again everyone..a lot of good info.