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tbeard

99 RLX shaft alignment redo.

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tbeard

New response owner working to dial in any issues from previous owner. Had a vibration issue so I replaced the prop and working on alignment.

After I aligned the 2 flanges within .004 parallel by adjusting the engine I did more research on alignment and realized I missed a step. I took the shaft coupling bolts back out and realized the 2 flanges were not in line (offset 3/16 inch). So I need to move the engine to align these 2 flanges - concentric of each other......then complete the parallel flange alignment process to meet the .003 requirement.

Question: With shaft resting in free state in the strut and prop still in place do I need to do anything with the shaft log coming out of the black sealed box sitting between the exhaust mufflers? That box is sealed and holds water and I hate to start taking it apart.....The shaft looks to be centered in the hull opening/hole. I did remove the packing nut to allow the shaft to sit in a free state in the rubber hose/brass log assembly. Shaft TIR run out is within .002 at both ends so I am confident it is not bent -just an alignment issue. Thanks......

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GreenMan

Sounds like you have it sorted.

Yes, I just undo the packing nut to eliminate that pre-load from the shaft. As long as the shaft isn't touching the side of the log housing. The other thing to check is if the strut bush is worn out and allowing the shaft to 'sag' lower than it would if the bush was a neat fit and holding the shaft parallel and concentric in the bush (hope that makes sense...).

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tbeard

Thanks Greenman......I assume the "Log Housing" is the brass housing bolted to the end of the black box the shaft runs through? So I will pull the rubber hose off that housing and look for clearance? I understand we do not want the shaft rubbing the side of that housing or pushing the shaft out of concentricity of the bushing in the strut?

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malibu2004

You don't need to loosen the packing gland. That's the big brass nut that holds wax rope (water drips in to lube the shaft) if you don't have a dripless packing gland. You just need to make sure you have the proper gap at 12,3,6 and 9 which is .003. Sounds like you did that.

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tbeard

To confirm that the packing Log flange bolted to the black box does not interfere with the shaft I will need to remove the clamps and pull the hose forward off the flange so I can look for interference. Or is that assumed to be a non issue?

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malibu2004

It sounds like you have a dripless. It's a none issue. Do you have any pic's by chance?

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GreenMan

Since you have indicated that you have a packing nut, you likely don't have a dripless seal but have a conventional rope packing type of seal.

I like to pull the clamped hose off as you described just to make sure that the hose hasn't been installed 'cocked over' a bit and is not pushing the log assembly hard against one side of the shaft and maybe deflecting the shaft from proper concentricity while you align the engine.

It may be that the mis-alignment you have has resulted in wearing an oval hole in the bore of the log. You should easily see it if so.

There's no need to break the seal on the 'black box' (HDS - 'Hydrophonic Damping System' I think) lid or log mount flange.

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malibu2004

Since you have indicated that you have a packing nut, you likely don't have a dripless seal but have a conventional rope packing type of seal.

I like to pull the clamped hose off as you described just to make sure that the hose hasn't been installed 'cocked over' a bit and is not pushing the log assembly hard against one side of the shaft and maybe deflecting the shaft from proper concentricity while you align the engine.

It may be that the mis-alignment you have has resulted in wearing an oval hole in the bore of the log. You should easily see it if so.

There's no need to break the seal on the 'black box' (HDS - 'Hydrophonic Damping System' I think) lid or log mount flange.

You talk of a clamped hose. What are you talking about? The only hose that I have is to cool the shaft because it's a dripless. You can also get a dripless without the hose. If it's a conventional packing nut it doesn't have a hose.

We might also being talking about the same thing but using different terminology since you are from Australia.

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tbeard

I do not have a pic here at work but I will try to describe the set up. Shaft comes out of the HDS through a brass flange. Brass flange has a ~ 2 1/2 dia. rubber hose ~ 4 inches long clamped to it. The other end has a packing nut assembly clamped to it. As shaft passes through HDS box and through the brass flange there is a chance the shaft could rub that brass flange (a hard mount) that has 2 bolts securing it to HDS box. If strut is off the shaft could rub that brass flange and put a bind in the system.....although it could be minor. While I have it apart I am going to remove the rubber hose and check for clearance and wear. I appreciate the feedback. Thx Oh I may sound like I am from Australia but actually I live in Texas:) LOL

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GreenMan

malibu2004, we're talking about the section of hose that connects the log assembly to the log mounting flange on the HDS box.

In this pic it's a black hose with two clamps at each end.

malibu2004 is referring to me - I'm Australian. Not sure what I sound like in print... :)

My 2005 RLXI in the pic is an Australian built model.

DSCN1675_zps7782e792.jpg

Edited by GreenMan

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tbeard

Yes......That's it! Thx GreenMan

Should I pull the log off that log mounting flange and look for clearance? Or just adjust the engine for proper alignment and move on?

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tbeard

Also any tips on how to access the rear engine mount adjustment nuts? The flexible exhaust tubes coming from manifolds to muffler are right in the way and they are not flexible:)

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GreenMan

Yes......That's it! Thx GreenMan

Should I pull the log off that log mounting flange and look for clearance? Or just adjust the engine for proper alignment and move on?

I prefer to slip the hose off the mounting flange just to make sure it isn't deflecting the shaft at all.

I've seen log housings that are heavily 'ovalised' due to the hose being installed crooked and pre-loading the housing. It's hard to tell just by feel or sight if this is occurring because the hose is so rigid and there is virtually no clearance in the log housing. You can install the log hose while the coupling flange is unbolted and free from the other hub and see if installing the hose results in noticeable deflection of the coupling.

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GreenMan

Also any tips on how to access the rear engine mount adjustment nuts? The flexible exhaust tubes coming from manifolds to muffler are right in the way and they are not flexible:)

I think I've just worked away in there with an open ended spanner (sorry, wrench...!) swapping sides to increment the nut bit by bit. Those 'flexible' hoses are a pain.

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tbeard

Ok Thanks...I got the left side off but right not so easy. Thanks will report back on progress.

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tbeard

Follow up to the low speed/vibration issue with my 99 RLX. First I want to thank everyone that provided input and helped guide to the fix. Long story short after 20 plus hours of working on this boat I am thrilled with the results. I have a video of the MPH and RPM if I can figure out how to post it:)

Results are with 1 passenger and full tank of gas.......48 MPH and 4900 RPM running the new Acme 449 13 X 12.625 with .080 cup. Hole shot is amazing, excellent throttle control and pulls a footer with excellent power. The boat is amazing smooth with zero vibration throughout entire range. FYI I am also running the Scarpa barefoot plate.

Things I did.....

1.Removed strut and installed new Vesconite bearings (I had to pay next day air to get them installed Friday but I am glad I did) The strut was slightly bent so I opened up the hull bolt holes by .060 which allowed me to tweak the strut alignment to engine. I made sure the 2 coupling concentricity was as close as possible in free state... even to where the 4 bolts would slide through freely without moving either coupling. All this allowed me to center the engine on the 4 mounts and start adjustment from there. Results of the alignment process was .002. I also found the sweet spot on the shaft log to prop shaft by turning the log until minimum drag was felt. Drove boat for 1 hour at slower to mid range speeds to seat the bearings.

2. Installed NGK plugs ....Gapped at .045

3. Checked timing.

4. Checked rotor

5. Cleaned Flame Arrestor

5. Changed oil

7. Added 10 Gal Mobile premium and Lucas fuel treatment.

Thanks.......Tom

Edited by tbeard

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GreenMan

Tom, great report!

Delighted all the learning and effort yielded worthwhile results. Sounds like you've done an excellent job.

Good work!

Enjoy. :)

Regards, Stephen.

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