1975 Omega Restore, the project goes on.

thrillhouse700

Senior Chief Petty Officer
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Aug 5, 2009
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778
My friend and I just picked up a 1975 Omega Trihull with a mercruiser l6. The front motor mount is sinking into the floor, the glass is cracked around the mount indicating some bad rot in the wood underneath. I have no idead where to start with this. How do I asses how much rot there is? I can only imagine it will be a lot more than just that area. Step one pull the motor? Then do I cut the glass around where the suspected rot is? Or does the whole floor need to come out? If anyone can give me a direction to start with it would be appreciated. thanks.
 
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Blade_Link

Seaman
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Aug 4, 2009
Messages
60
Re: 1975 Omega Rot, Don't know where to start.

Re: 1975 Omega Rot, Don't know where to start.

your best set would be to pull the motor and everything, take the floor right out if one area is bad the whole floor wont be far behind, so you willl be better off to replace the whole thing
 

thrillhouse700

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Re: 1975 Omega Rot, Don't know where to start.

Re: 1975 Omega Rot, Don't know where to start.

Apologize for my ignorance but taking the floor out would include cutting it out? I have seen pics of your guys restos where the top and bottom shell has come apart. Do I have to do that? I have the tools and time, just have to talk it over with my friend and see if we really want to dive into this.
 

oops!

Supreme Mariner
Joined
Oct 18, 2007
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12,932
Re: 1975 Omega Rot, Don't know where to start.

Re: 1975 Omega Rot, Don't know where to start.

if you do decide to do this.....as suggested.....rip it all out.....its not that hard....

i just did a 78 campion with a chain saw right to bare hull....it only took me 16 hrs ..(didnt take the cap off)..the rebuild will be a bit longer but after every thing is out...it will be way easyer than tip-tow-ing around old peices of glass and deck...

need to see pics of your boat before i can tell you if the cap has to come off....but dont worry about that....that part is really easy and youll be glad you did it....(if you have to)

use a circ saw to cut the outer boundry of the existing deck......that will give you your deck height.....after you have your straight cuts done....get out the electric chain saw.....and start ripping.......

cost...aprox 800-1500 full
time...between 40 and 200 man hours.
diffuilcty....7.5
satisfaction....priceless

cheers
oops
 

oops!

Supreme Mariner
Joined
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Messages
12,932
Re: 1975 Omega Rot, Don't know where to start.

Re: 1975 Omega Rot, Don't know where to start.

by the way....welcome to i boats....:D
 

thrillhouse700

Senior Chief Petty Officer
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Messages
778
Re: 1975 Omega Rot, Don't know where to start.

Re: 1975 Omega Rot, Don't know where to start.

I am mechanically inclined and so is my buddy, He has worked on more boats than me and we have both been in the auto industry for some time. I have pulled my share of motors but Im assuming a cherry picker wont raise up high enough. Any ideas of how the engine removal should be done? what tools I need or if possible rent?
 

78ImperialT

Petty Officer 1st Class
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Jul 25, 2009
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Re: 1975 Omega Rot, Don't know where to start.

Re: 1975 Omega Rot, Don't know where to start.

welcome to the forum!!

rip it all out! then do some core samples
 

thrillhouse700

Senior Chief Petty Officer
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Aug 5, 2009
Messages
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Re: 1975 Omega Rot, Don't know where to start.

Re: 1975 Omega Rot, Don't know where to start.

still not quit sure how to get the engine out, any tips on how to do it at home?
 

Rickairmedic

Commander
Joined
Apr 24, 2009
Messages
2,576
Re: 1975 Omega Rot, Don't know where to start.

Re: 1975 Omega Rot, Don't know where to start.

Gantry crane is the easiest way you can make one out of 4X4's and such . Roll the boat under it lift the motor and roll the boat back out :D.

Rick
 

thrillhouse700

Senior Chief Petty Officer
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Re: 1975 Omega Rot, Don't know where to start.

Re: 1975 Omega Rot, Don't know where to start.

Here is a photo of the motor mount.

DSC00377.jpg
 

thrillhouse700

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Re: 1975 Omega Rot, Don't know where to start.

Re: 1975 Omega Rot, Don't know where to start.

A small Update with some pics, Today we got the Drive off and realized it probably hasn't been serviced in god knows when. Pulled up all the carpet and pulled off side interior panels. Motor will be coming out next week some time. Found a buddy who will be able to remove it with a forklift. Found two water entry points so far, the boot for the u joints and the lower bolts for the drive are loose.

Front area of the motor mount box where it meets the bilge. Should this be open in the corners?

We have got a long list of parts that we need so far, but any other parts that are recommended will be added to the list.

The drive selector gear looks like it has been gnawed on by a forest creature, cant seem to find it on the iboat parts list. Should this have some for of seal to make it water proof because ours does not.

Anyways thanks for all the input so far, I will continue to post pics of progress.
 
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singinout

Petty Officer 1st Class
Joined
May 20, 2009
Messages
339
Re: 1975 Omega Rot, Don't know where to start.

Re: 1975 Omega Rot, Don't know where to start.

Welcome to iboats! Also welcome to the "unofficial" trihull club! There's a few of them on here. Great to see another one! Gud luck with your project!!
 

thrillhouse700

Senior Chief Petty Officer
Joined
Aug 5, 2009
Messages
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Re: 1975 Omega Rot, Don't know where to start.

Re: 1975 Omega Rot, Don't know where to start.

Thank you singinout, I like your boat too!
 

thrillhouse700

Senior Chief Petty Officer
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Messages
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Re: 1975 Omega Rot, Don't know where to start.

Re: 1975 Omega Rot, Don't know where to start.

Anyone make any suggestions on where to go from here?
 

ben2go

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Jul 29, 2008
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411
Re: 1975 Omega Rot, Don't know where to start.

Re: 1975 Omega Rot, Don't know where to start.

You need to seriously check the transom and stringers out for rot.Don't skimp out here.Your passengers as well as your safety will be at risk.Replace them keep the boat securely on the trailer so it doesn't flex or twist when you reinstall the new ones.Go slow,take pics,take measurements,take notes,and work on one side at a time.Slow and steady always gets the job done safely.
 

thrillhouse700

Senior Chief Petty Officer
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Aug 5, 2009
Messages
778
Re: 1975 Omega Rot, Don't know where to start.

Re: 1975 Omega Rot, Don't know where to start.

Yeah we had planned on ripping up the floor like someone said above, We are waiting for the motor to come out, then up comes the floor, How do you check the transom?
 

ben2go

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Jul 29, 2008
Messages
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Re: 1975 Omega Rot, Don't know where to start.

Re: 1975 Omega Rot, Don't know where to start.

Most people tap on the inside to feel for soft spots and listen for hollow sounds.If I decide the floor is coming up,I replace the transom and stringers.Once there is water intrusion, mold soon follows.It only takes one mold spore to start the new wood to rotting all over again.
 

thrillhouse700

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Messages
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Re: 1975 Omega Rot, Don't know where to start.

Re: 1975 Omega Rot, Don't know where to start.

Ok cool, I will take pics once we get the engine out and the floor up. Thank you everyone for the help so far. One of the more helpful forums to noobs. Once again thanks.
 

thrillhouse700

Senior Chief Petty Officer
Joined
Aug 5, 2009
Messages
778
Re: 1975 Omega Rot, Don't know where to start.

Re: 1975 Omega Rot, Don't know where to start.

Today we got the motor out and cut the motor mount box out so we can take a look, all the foam was soaked and very heavy, there is only one center stringer that we can see, is this normal for a trihull? When we removed the motor mount box we can tell that someone attempted this repair previously. You can see where the fiberglass had been cut away and there was 2 2x10s stacked up and then glassed over. Anyways here are the pictures

Here is the front of the stringer, shouldnt it go all the way back to the transom? It is in no way attached to it, The other two sides of the bilge are not connected to the stringer at all.

That is all we got done today since I spent most of the day borrowing the cherry picker. I was going over a bunch of older boat restore threads and read that you should do the transom first because if you take the cap off and the floor and the transom out the boats hull will distort. So my question is where do I go from here?

I'm assuming remove the rest of the drive and gas tank and then check the transom for rot? Someone mentioned earlier to take core samples? How would I go about doing this? Secondly, if the transom is rotten and needs to be replaced can this be done without popping the cap or does that have to come off first? I am going to prepare for the worst and hope for the best here. Transom looks to be pretty thick, is everyone using 3/4 plywood? Do I have to get marine or can I just get exterior grade? Thanks guys once again. I will keep spending countless hours reading all of your other threads because I have learned more about boats and how they are made in the last week than I ever have.
 
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seven up

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Jun 4, 2006
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Re: 1975 Omega Rot, Don't know where to start.

Re: 1975 Omega Rot, Don't know where to start.

I've gotta commend you for jumping right in. You are already taking the best route and reading through the other threads on stringers and floors. Basically just replace what you take out. You can save alot of the old stuff for templates to make exact copies. Great looking boat.

A core sample would be drilling a (sometimes several) small hole into fiberglass component that has a wood core like a stringer. You just want to check the condition of the wood that comes out with the drill bit. You may not want to drill entirely through the piece being tested.

For replacing plywood panels, stringers and transoms it is urgent that all the edges of the newly constructed replacement panels be sealed. Even better: the tops and bottoms, too.
 
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