Front motor mounts stripped

1979 Quartermasters

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May 30, 2009
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505
Hi again.Yesterday I took my 1979 Bayliner, 140 horse Mercruiser for a test run and after cruising for a while we stopped to check our repairs from yesterday. All seemed well, so I accelerated hard to plain and the boat was leaning hard to port (left?). It became fairly hard to control so we headed back to dock to investigate further. We couldn't see a problem yesterday. Today I discovered the front engine mounting bolts were loose. I pulled them out by hand. I think when I hammered on it that last time I pulled those lag bolts out and the motor was jumping around causing the irratic behavior. I'm going to try to include some pictures. What would the best way to repair this problem. Thanks.
 
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coastalcruiser

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Aug 2, 2007
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Re: Front motor mounts stripped

With a 79 boat you probably have some rot where the lagbolts were.
To correct the list to port (left) I use trim tabs... failing that you can distribute weight and or people around the boat. just behind the propeller there is a zink that can be turned a few degrees to offset the drives tendency to turn the boat to port. sometimes the steering gets loose.
older boats can have multiple problems.
 

1979 Quartermasters

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Re: Front motor mounts stripped

The bolts are completely loose and nothing is holding the motor to the bottom of the boat. Do I need to block the motor up, remove the mount and replace the material that the lag bolts were screwed into?
 

coastalcruiser

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Re: Front motor mounts stripped

1979 Quartermasters The bolts are completely loose and nothing is holding the motor to the bottom of the boat. Do I need to block the motor up, remove the mount and replace the material that the lag bolts were screwed into?

If you move the motor enough to fix the holes your drive alignment will likely go out of adjustment, that will cause your engine coupler to wear out prematurely.
Most people suggest you check the alignment and drive u joints, gimbal bearing etc every year anyway.
I guess you could always try a fatter lag bolt but it will just prolong the inevitable...In my boat I replaced the wood with new 4x4 fir ones, they are glassed in and gel coated.
 

Fishermark

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Oct 19, 2003
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Re: Front motor mounts stripped

The bolts are completely loose and nothing is holding the motor to the bottom of the boat. Do I need to block the motor up, remove the mount and replace the material that the lag bolts were screwed into?

That's the least of what you need to do. While you are at it, you might want to check the condition of your transom as well. My experience has been when there is rot in one, there is rot in the other as well. Both will continue to cause problems until they are repaired.
 

1979 Quartermasters

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Re: Front motor mounts stripped

Would I remove the existing fiberglass, remove the existing wood, clean he area. Fit a new piece of fir and fiberglass over all of that. Would I use the sheets of cloth with resin or could I use long strand in a can?
 

coastalcruiser

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Re: Front motor mounts stripped

I would go with the fiberglass cloth and resin. epoxy resin will stick better.

another way could be to drill out the lag holes with a 2'' hole saw. cut new wood plugs and epoxy those in. Carefull not to go too deep!
 

cr2k

Captain
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Mar 19, 2009
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3,730
Re: Front motor mounts stripped

You could also find a piece of like 3 or 4 in angle aluminum (or iron I guess) span it across the stringers (trimming the down end to fit inside the stringers) over the front rotted piece and lag in to the stringers and then drill and tap the angle for your front mounts. Be sure to adjust for the height difference. Best to do with the drive off and then re-align before you put it back on. This is a fairly simple fix and (barring any other structural rot) should last for quite awhile.

Just remember, where you are now, regardless of what you do from here, you need to pull the drive and realign the engine or risk (high probability) damaging your engine coupler.
 

Howard Sterndrive

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Nov 5, 2008
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Re: Front motor mounts stripped

how could loose engine mounts be affecting the steering of the boat when it`s Mercruiser powered? OMC stringer, sure...but wow- this boat has serious issues
.. like maybe the stringers, transom and hull are completely rotten and the fiberglass shell is bending all over.
Wear your life jacket.
 

Robj

Lieutenant
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Mar 22, 2007
Messages
1,441
Re: Front motor mounts stripped

I'd put huge $$ on it that here is more rott than just the motor mount. I would start looking at the stringers and transom as well. That boat is unsafe as is and should be fixed before it goes back on the water. If you jerry rig the mounts with a piece of angle, and the angle is fastened to rotten stringers, that probably creates a more dangerous situation than what you currently have.

Have a great day

Rob.
 

1979 Quartermasters

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Re: Front motor mounts stripped

It really didn't affect the steering. Under hard acceleration and wot it seemed to list to port. It steered fine. I guess what i am wondering; is it worth it to try and fix this boat. I recently bought this boat thinking I new what to look for when buying a boat. Turns out I was wrong. I have quite a bit of money in the end drive, new gimbal bearing, trim seals, major tune-up and numerous other fixes. I am a renovation carpenter and auto D I Y'er mechanic and not afraid of a challenge. I don't really know the structure of the boat or where to begin. A point in the right direction would be a great help. I was out there looking a little deeper and I think you are right about the rot.
 

coastalcruiser

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Re: Front motor mounts stripped

I do renos too. also worked for awhile in a boat building shop.
Pm me with any questions.
Check out boat building and restoration and completed projects here at iboats
ebay for an alignment tool, rig up some way to pull your engine, check out youtube for fiberglassing skills. test areas that your suspicious of with core samples, use a drill and a 1/4 '' bit.
Just like a house rot has to go.
This forum is really useful and as you noticed people really tell it like it is!
 

bigskiohio

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May 3, 2008
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Re: Front motor mounts stripped

for now bigger lags would do till season is over.
 

Howard Sterndrive

Rear Admiral
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4,603
Re: Front motor mounts stripped

Take a big ice pick or awl and start poking at all the wood inside the boat. It might be fine or it might be junk ...but rotten wood is easy to find with some poking.
 

WizeOne

Commander
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Mar 23, 2008
Messages
2,097
Re: Front motor mounts stripped

I feel for you 1979 Quartermasters. It's bad enough when you've owned the boat for a long while and it unsuspectingly rots out from under you, but to have recently purchased the boat and to be slapped upside the head with these issues is a hard hurdle to get over. But if you like the boat, and as you say you have many capabilities, a lot of satisfaction can be had learning and making things right.
 

1979 Quartermasters

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Re: Front motor mounts stripped

Today I took my boat out to test after putting oversized lag bolts in. When on plain the boat lists to port but continues to travel in a straight line. If I turn the wheel to the right to level it the boat turns slightly to the right. The motor seems to be secure as it is not moving around while I am cruising. The trim tab, over the prop, has not moved and was adjusted correctly I can't see what is causing this problem. It has been working fine all summer and suddenly I'm having this problem. I don't know what to do or where to look next. Any help would be welcome.
 

coastalcruiser

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Re: Front motor mounts stripped

my boat is a deep V hull and always lists depending how fast i'm going. for example if i'm loaded with water and or people etc.
Simple problem to fix with trim tabs.
They let you fine tune the list and also can lower the bow, that helps to get on a plane and in choppy water! also works for "porposing" if you get that going fast
Here are my bennet tabs they are un-screwed for painting


Image001.jpg
 

fishrdan

Admiral
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Jan 25, 2008
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6,989
Re: Front motor mounts stripped

I had the same problem on my ol 72 SeaSwril and oversized lags stripped out after a while because of rotten wood. I JB Welded in metal lag bolt anchors and never had a problem again,,, but was riding around in a boat with serious rot damage.

Like other's have said, investigate the rot damage and repair correctly, I took my rotted hulk to the landfill as it wasn't worth repairing...
 

1979 Quartermasters

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505
Re: Front motor mounts stripped

These are good ideas and I am greateful for the help, but I guess what concerns me is that it didn't do all summer and now for no reason its leaning. When driving the boat seems to wander a little at an idle with little play in the steering wheel. Since this all began the boat seems to handle funny at wot. The response to the steering wheel has changed. I'm still stumped. I changed the angle of the trim tab and will try that. The ride has changed enough that I am afraid to take my kids in the boat. I guess I'm going to park it unless we come up with some thing.
 
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