Rotten Stringer at Motor Mount

[noserider]

After installing my 4.3 mercruiser in my crownline i was unable to tighten the bolts on one side due to soft wood (rot). Has anyone had any luck using Marine Tex or Git Rot sold as West Marine. I was hoping to put the product in the bolt holes and screw/hammer down the bolts and let it dry. I'm hoping it will work for a few more seasons. Anyone tried this approach?

Thanks

 

[Bob_VT]

Re: Rotten Stringer at Motor Mount

Worst Marine will rob you blind! You need to investigate the extent of the rot before you attempt a band aid repair. Engine mounts are critical and I would not want to see one fail. If you use a product in a rotted area it will not make it stronger..... the rotted area needs to be properly repaired

Once you determine the true extent of the rot we can guide you to a safe repair.

 

[noserider]

Re: Rotten Stringer at Motor Mount

Thanks

 

[noserider]

Re: Rotten Stringer at Motor Mount

Guys

We took the boat to a fiberglass boat guy today. Even though one motor box seemed solid we decided that it was best to rebuild both boxes while we are in there and the engine is out. The motor boxes have a short stringer on each end. One goes to the transom and the other one goes toward the bow and intersects another at a 90 degree angle. The price to open it all up and replace the wood and glass it in was $450.00. Very fair i thought. I generally tackle all my own jobs but it was to tempting to have a pro do this one for that price. I pulled the engine and tranny and will reinstall it when the stringer repair is done next week.

 

[noserider]

Re: Rotten Stringer at Motor Mount

Guys

How do you go about making sure the new front motor mount bolt holes are in the same spot as before after the wood has been replaced and glassed over?

 

[jonesg]

Re: Rotten Stringer at Motor Mount

I'm an outboard guy but common sense tells me measure before removing the old.

$450 sounds terribly cheap for this, but you're doing the heavy work of remove and replace so...

Give it a good cleaning and bilgecoat paint before dropping the engine back.

 

[noserider]

Re: Rotten Stringer at Motor Mount

The rear mount holes will not be changed so I guess I need to be concerned about the side to side position of the new front mounting holes?? Any thoughts ??

 

[noserider]

Re: Rotten Stringer at Motor Mount

bump

 

[lrcustom]

Re: Rotten Stringer at Motor Mount

noserider,
First do a very good amount of measuring top view mounts off of the transom and the sides. realize that the mount is a pad much larger than the motor mount. measure it 's size it's height and it's taper if it has one. you will need to rebuild the mount back as it is. now the Bolt that goes in the mount. needs to be set when you replace the motor and only after you have aligned the engine and out shaft. there is plenty of info in the motor section. I found lots when I did my Merc. in the Sea Ray realize that the forward bolt and it's leveling is the last item on the reinstall. just do a great job replacing the mount to where it suppose to be and everything else will work out right. Follow the engine install and alignment proceedure and it will work.

LR

 

[Yacht Dr.]

Re: Rotten Stringer at Motor Mount

Hello m8..

I agree with jones on 2 fronts..

1. $450 is kinda lowball for cut/grind/fit new wood/prep/glass/materials and cleanup..

2. The locations of All mounting brackets should have been templated/measured before removal..

Look at what adjustments you can work with on your motor mounts and the mount point/brackets. ( up down side to side thing )

Measure .. measure and when you Think you have it drill one hole at a time .. measure again..drill ..

Then when you have all your holes drilled .. remove the motor and properly seal your mounts holes/fasteners to stringers (5200).

Final step is put in the water and have it alligned..

Im no Mech Tech so this is what I have to offer..

YD.

 

[noserider]

Re: Rotten Stringer at Motor Mount

Hello m8..

I agree with jones on 2 fronts..

1. $450 is kinda lowball for cut/grind/fit new wood/prep/glass/materials and cleanup..

2. The locations of All mounting brackets should have been templated/measured before removal..

Look at what adjustments you can work with on your motor mounts and the mount point/brackets. ( up down side to side thing )

Measure .. measure and when you Think you have it drill one hole at a time .. measure again..drill ..

Then when you have all your holes drilled .. remove the motor and properly seal your mounts holes/fasteners to stringers (5200).

Final step is put in the water and have it alligned..

Im no Mech Tech so this is what I have to offer..

YD.

Guys

Thanks for all the advice. The motor is out and the boat is at the fab shop. I'll go by before they begin the work and take some good measurements and discuss these items with the shop guys to make sure we are all on the same page.

 

[oops!]

Re: Rotten Stringer at Motor Mount

when you drop in the motor after the job is done....

and YD is correct.....thats a low ball.

the motor is dropped in.....the two bolts that connect the bell will give you basic alignment...
those go in AS the motor is being dropped in. (make sure the phenolic washers and spring washers are in good condition and correctly in place)

stick the alignment tool in and see how much the motor has to come up or down. (remember...you are only adjusting the side to side height) the rear height is allready taken care of)

the left right mounts will have to be adjusted up and down with the new mount height.

then use the alignment tool again to make it perfect.

THEN THE HOLES ARE MARKED AND DRILLED.

motor pulled...(or lifted) and use standard sealing practices for the lag holes...

drop the motor back in......re check the alignment....do your hook ups and go fishing !

i can do a new motor drop in and drill the holes and seal in under 30 minits. its really easy.

if the guy does a decent job and hits the correct height......you may not even have to raise or lower the mounts.

make sure your alignment is bang on...or its a gymball berring next year for you.

cheers
oops

 

[series60]

Re: Rotten Stringer at Motor Mount

One this subject of aligning the new forward motor mounts, is there a diagram or picture of a jig a person could build to assist in the placement of the new stringer mount positions? I have my Mercruiser 305 out and was hoping for some solution for getting the fwd mounts at the correct height and distance from the rear mounts.