Rear Engine Mounts Question - 1994 Four Winns Sundowner 215

platinumedge

Petty Officer 3rd Class
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Aug 12, 2018
Messages
93
This boat has a Volvo-Penta combination with a 5.8L EFI Ford engine. I removed the engine last week (no real problems), but really just raised it up enough so I could re-insert a couple of freeze plus. I lowered it back down most of the way and got the bolts started in the front engine mounts. Then I lowered it the rest of the way so the rear mounts lowered over the studs, and got the lock nuts started back there. I then torqued all mounting nuts/bolts to their specs. Everything seemed fine.

I have been taking pictures of all the "little things," like smaller bolts, screws, and fasteners, as I go. However, I neglected to take pics of the rear engine mounts prior to removing the engine. Yesterday I noticed that the number of threads protruding above the locknut on the starboard rear mount was significantly less that the number threads showing on the port mount. I removed the locknuts again, just now, and I can't see, nor feel, any gaps underneath. Is it "normal" for the engine to be "shimmed" up higher on one mount? I'm assuming the factory makes these types of adjustments due to boat manufacturing differences, but wanted to ask you folks.

Thank you kindly.

P.S. The alignment tool slides in just fine!
 

Bondo

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Apr 17, 2002
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70,524
P.S. The alignment tool slides in just fine!

Ayuh,..... That, ^^^, determines where the nuts end up,.......
 

platinumedge

Petty Officer 3rd Class
Joined
Aug 12, 2018
Messages
93
Thanks, Bondo. That's what I was hoping to hear

But, just to be clear, I made NO changes to any of the mounting bolts/screws. I merely raised the engine, worked on it for an hour, and dropped it back in place. So it's normal for those lock nuts on the rear mounts to be at different heights, right?
 

PITBoat

Petty Officer 1st Class
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Jul 26, 2018
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286
Intuitively, it doesn't seem like it would be necessary to have one side of the motor higher than the other, if the axis of rotation is simply the hole where the shaft goes in. But I'm just guessing.
 

platinumedge

Petty Officer 3rd Class
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Aug 12, 2018
Messages
93
PITBoat, that's kind of what I was thinking, but I can't conclude that "one side of the motor is higher than the other." I believe, based on logic and Bondo's response, that no fiberglass hull is perfect, and no engine mounts are perfectly placed during production. Which leaves the engine/transom/outdrive installers the task of creating a vibration-, and binding-free propulsion system. Plus, I can't really tell if one side of the engine is higher than the other, since I can't tell if the boat/trailer is level.

Since I removed the rear engine mount lock nuts today, to inspect things, I wasn't able to easily insert the alignment tool. After reinstalling those locknuts, and tightening them to spec,, the alignment tool, again, can be easily inserted.

Bottom Line: I don't currently believe that one side of the engine is higher than the other. I believe that the starboard side was lower during the initial installation. But the installers increased the height of that rear starboard engine mount to compensate.

I plan to investigate this further, so if anyone has additional experience or input, I would greatly appreciate it.

Cheers to all!
 

platinumedge

Petty Officer 3rd Class
Joined
Aug 12, 2018
Messages
93
While looking at some other items near the rear of the engine today, I noticed that the lower washer on the rear, starboard engine mount was loose! After doing a bit of investigating I uncovered the reason for the locknut not going down as far as on the port mount. I didn't realize it at the time, but the bolt coming up from the bottom of the mount actually threads through the mount. For some reason, when I re-installed the port mount locknut, the bold "held." However, when I reinstalled the starboard locknut, the bolt loosened and "backed itself down." Eventually the locknut found a point where it tightened but left the head of the bolt well below where it should be.

I see that the solution is to screw the bolt all the way up, clamp the bolt from below, and then tighten the locknut from above. This procedure is similar to securing the front engine mounts, but the head of this bolt is much more difficult to access/clamp.

I've tried to imagine scenarios where I never discovered this: While running the engine (probably at any speeds), the bolt could start loosening, due to normal vibrations. Eventually that rear, starboard mount would become loose and allow the engine to shake, rattle and roll beyond normal expectations. With some things having "flexible" connectors, such as the exhaust risers, you might think the vessel could continue on. But I also think that the direct connection to the outdrive would suffer from the larger vibrations, and eventually produce a catastrophic reaction, resulting in a failure of the transom assembly, or other key components.

So, even though the alignment tool fit easily, this is a lesson to show that one needs to investigate anything that looks unusual after reinstalling an engine. In my case, I think I can avoid pulling the motor again, and just insure that that rear, starboard engine mount is drawn down securely.

I was hoping to put this baby into the water this year, but it's looking less likely as the days go by. :-( Someday...
 
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