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93 Model 572 VibrationNoise

E

epj

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Pulled boot back U-Joints look

Pulled boot back U-Joints look ok no play no Water drive in good shape new in 1999 about 250 hrs. Props were bent got them reworked and it made a big difference. Could bad engine mounts be causing Vibration/Noise ?
 
"Is this your type of bellhous

"Is this your type of bellhousing?

http://www.volvopentastore.com/FLYWHEEL_COVER_PRIMARY_SHAFT_AND_CLAMPING_RING_KI T_LATE_TYPE/dm/store_id.366--session_id.673718239--cart_id.576176356--category_i d.332087--list_time.1186499823--view_id.314400

If so, chances are that the noise and vibration are being caused by the ball bearing (part 4), which is probably in rough shape. That bearing is difficult to grease in that particular type of bellhousing, because there is no grease fitting installed. I found a way of pumping grease to the bearing, but the advice I got time ago was to replace the original bearing with a sealed bearing."
 
"It may be the bearing, It has

"It may be the bearing, It has over 500 hrs. That looks like my Bellhousing, 572PS DPC1 There may be more bolts around the clamp. when I pulled back the boot I saw clean grease around that bearing/Seal I am trying to make the end of the seaon about 5-10 more hours. I am wondering how to do an engine alignment. I do have to pull the engine to replace that bearing don't I. I posted last year on a high speed miss a tune up fixed it temporarily, I had to replace Manifolds. See this http://www.marineengine.com/discus/messages/12487/26158.shtml"
 
"The way I have done the engin

"The way I have done the engine alignment is by attaching the bellhousing to the transom shield without the engine, then measuring the distance between the end of the primary shaft and the inner part of the keel in the bilges. Once I install engine and bellhousing together, I keep that same distance between the center of the vibration damper bolt and the inner side of the keel in the bilge. Also, the notches in the bellhousing and transom shield must be aligned. For this, you adjust the height of the side mounts.



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"I recently replaced the strin

"I recently replaced the stringers in my boat and had to remount the engine. I used a slightly different technique.

First I installed the motor mounts and stantions on the engine. Next I picked the engine with a hoist and attached the bellhousing. I then lowered the entire assembly into the boat and through the transom shield. I installed the rubber o-rings and threaded the bolts onto the clamp ring hand tight. With the motor mounts hanging slightly above the stringers I rotated the assembly until the three tick marks (noted by El above) where within reasonable alignment - rotationally. My dad then snugged up the bolts on the clamp ring pulling the tail of the bellhousing fully into the transom shield. I then lowered the assembly bearing weight onto the motor mounts. Using a piece of keystock and feeler gauges I then measured the the distance between the transom shield assembly and the bellhousing at each tick mark. By adjusting the front motor mounts up, or down, and using a bar to move the engine port, or starboard I was able to align each tick mark within 0.01". Once aligned I drilled holes into the stringers and lagged in the motor mounts. I then torqued the clamp ring to 27 ft-lbs and bent over the stainless lock bar.

Aligning each tick mark ensures that the primary shaft in the bellhousing will rotate in the same plane as the crankshaft thereby prolonging the life of the gimball bearings and outdrive u-joints."
 
"Mike, your alignment method i

"Mike, your alignment method is obviously valid; but I always thought that, on a VP AQ, the bellhousing is what makes the primary shaft run straight regardless of how well the bellhousing is aligned with the marks on the transom shield. To me, aligning the engine height has more to do with minimizing stresses in the area where the bellhousing meets the transom shield. The bellhousing is quite stiff and I don't see the primary shaft bending no matter how misaligned it may be. Remember that some old VP AQs didn't even have engine mounts !!!( a bad thing, IMO). One of the advantages of Volvo Penta AQs versus Mercruisers is that the shaft alignment is not as critical in the former when compared with the latter. In VP, it is virtually impossible to do it wrong, while with Mercruisers, I recall that a special tool is needed to align the gimbal bearing with the engine coupler.

Also, keep in mind that the u-joints are there for the outdrive to run at an angle different than the primary shaft's. As yo know, the transom shield has either a 3-position trim pin, or power trim; and it also has power tilt."
 
"Sounds like a good method! So

"Sounds like a good method! So the transom shield does not bolt up solidy to the bellhousing? The Bearings that support the primary shaft are in the bellhousing! I will learn alot this fall. I have limited access to a Certified VP Tech. who installed the new drive on this boat a few years back before I purchased it. He may make house calls for a fee. I made an makeshift Stethascope and cannot hear any difference from the bearing housing at the rear and the main bearing seal at the front of the engine, it sounds fairley quiet except for the valve train common sounds."
 
"El you took some of the words

"El you took some of the words out of my mouth, Your post got ahead of mine! Thanks everyone for all the feedback! I was an outboard Man and always favored Merc-Cruiser but through this forum I am learning alot I do not know of many Merc's 16+ years running on the orgional Primary Bearings (Gimbal)"
 
One More Question! If I have t

One More Question! If I have the single bearing do I have to pull the Engine/Bellhousing to replace it!
 
"Yes, you must remove it if yo

"Yes, you must remove it if you want to do the job properly. It is possible in some instances to do the job without removing the bellhousing, but I would not recommend it. Amongst other things, you would not be able to replace the inner lip seal, and you won't be able to see if the pilot ball bearing (part 12 in above link) remains in place inside the crankshaft or it has fallen while removing the primary shaft; nor you can evaluate the condition of the spline and absorber bolts. I know it is a bit of a PITA to pull the engine, but that is the only safe way I believe the job can be done.

Again, consider using a sealed bearing if you are going to replace it."
 
I could not hear any differenc

I could not hear any difference with my makeshift Stethascope between the front of the engine close to the crank and the rear where the bearing is. Hopefully it is not that bad and I will be able to finish the season about 6 or 8 hours (Labor Day Weekend)and a little more. I will make the necessary repairs in the off season. Thanks for the response
 
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