New pics added 11/30 - 86 Grumman 184 turned out to be more of a pjt than exptcd

[mikezohsix]

Re: NAKED pics added - 86 Grumman 184 turned out to be more of a project than expec

Re: NAKED pics added - 86 Grumman 184 turned out to be more of a project than expec

update....om material

I ended up calling West Systems and was told about G/Flex, which comes in a thickened or unthickened consistancy. It is a two part epoxy that has a 30% elogantion factor as opposed to 5-8% for normal marine epoxies. That means it has the give of the polyeurathane glues like 3M 5200, but the adhesion of an epoxy.

West Systems has an aluminum prep kit (PN 860 something) that is used to remove and prevent further oxidation/corrosion. It is an acid wash and alodine. It also improves the adhesion of the G/Flex 855.

 

[mikezohsix]

Re: New pics added 11/25 - 86 Grumman 184 turned out to be more of a pjt than exptc

Re: New pics added 11/25 - 86 Grumman 184 turned out to be more of a pjt than exptc

the transom is done and has been test fit in the boat, and all holes have been tranfer drilled. I glued three sheets of 3/4 AC ply together with PL poly adhesive, and screwed the sheets together while the glue was setting. I then pulled the screws and glued and screwed the next layer on. Here's how it glued together on a piece I trimmed off the transom. Note the glue is forced down the empty screw hole and how thin the glue line is...

I cut the hole for the outdrive, and test fit it...

I then covered the transom in 6 oz glass, using system 3 epoxy, which I got from a local resin and glass supply house called Merlon's in Springfield MA. The owner is super nice, it's a small shop and he spends the time to help you.

F/G'd transom...

x

Here's the semi-finished transom in the boat with the outdrive test fit when I transferred all the thru holes...

Right now the transom has just had a second coat of resin, and all the new thru holes have been coated with resin. It's ready to go in when the metal work is done

 

[mikezohsix]

Re: New pics added 11/25 - 86 Grumman 184 turned out to be more of a pjt than exptc

Re: New pics added 11/25 - 86 Grumman 184 turned out to be more of a pjt than exptc

for the tin work....

the corroded areas have been lightly sandblasted and been etched and alodined using the West Systems aluminum prep kit. The bolt thru holes have been drilled in these pix...

port side looking along the transom at the side of the hull.

stbd side looking along the transom at the side of the hull.

These are the two doublers I made up dry fit in the corners. Note that they're flanged to step up over the three different rivet lines. That's 3 1/2 hours of tin knocking...

stbd side looking along the transom at the side of the hull.

port side looking along the transom at the side of the hull.

They're glued in and thru bolted. Came out great. There are going to be no issues in these areas in the boat ever. The G/Flex epoxy is setting up now, I'll put pics up tomorrow.

I have to put this picture of my wife up. She's been a sport helping me get the transom in this morning for the test fit, and putting up with the saw dust and resin smells. She had a "good feeling about this boat", which I didn't want when I saw the corrosion. It's been a project.

 

[andgott]

Re: New pics added 11/25 - 86 Grumman 184 turned out to be more of a pjt than exptc

Re: New pics added 11/25 - 86 Grumman 184 turned out to be more of a pjt than exptc

Looks good- That should be one solid transom!

I've never done a metal boat before- Someday, Perhaps....

-Andrew

 

[BobsGlasstream]

Re: New pics added 11/25 - 86 Grumman 184 turned out to be more of a pjt than exptc

Re: New pics added 11/25 - 86 Grumman 184 turned out to be more of a pjt than exptc

mikezohsix,
That really looks great.
The last tin boat I did was two 53 Buick hoods welded together about __ years ago.
In my youth. :redface:
Looks great Mike.
Bob

 

[system-f]

Re: New pics added 11/25 - 86 Grumman 184 turned out to be more of a pjt than exptc

Re: New pics added 11/25 - 86 Grumman 184 turned out to be more of a pjt than exptc

That transom wood looks beautiful. What is the final thickness? I thought that cobra drives were limited to a 2 1/8" thickness like Merc drives? Maybe it was 2 1/4".

 

[mikezohsix]

Re: New pics added 11/25 - 86 Grumman 184 turned out to be more of a pjt than exptc

Re: New pics added 11/25 - 86 Grumman 184 turned out to be more of a pjt than exptc

That transom wood looks beautiful. What is the final thickness? I thought that cobra drives were limited to a 2 1/8" thickness like Merc drives? Maybe it was 2 1/4".

I measured the original transom at 2 1/4 - didn't measure it real carefully. It's gone into the wood furnace because the carpenter ants were still alive in parts of it, so I can't go back and measure it again.

The new plywood thickness is just over 2 1/8, not sure what the glass will add for thickness, maybe another 1/8th. The transom aluminum is probably .100, haven't measured it

Why would there be a limit, within reason, on the thickness of the transom?
As long as you get good thread engagement on the studs everything should be ok - right?

 

[superpop]

Re: New pics added 11/25 - 86 Grumman 184 turned out to be more of a pjt than exptc

Re: New pics added 11/25 - 86 Grumman 184 turned out to be more of a pjt than exptc

I don't think the stud and bolt engagement is the issue with the thickness of the transom but rather, how much of the shaft from the drive, seats into the coupler. Not enough and you will trash the coupler.

 

[mikezohsix]

Re: New pics added 11/25 - 86 Grumman 184 turned out to be more of a pjt than exptc

Re: New pics added 11/25 - 86 Grumman 184 turned out to be more of a pjt than exptc

I measured and I'm at 2 1/4 for the finished transom.

With inches of engagement in the spline, I'm sure a 1/4 to 3/8 inch won't make any difference. Especially since this is a low performance 4 cyl engine that isn't going to be turning north of 3500 rpim too many times in it's life.

I have the factory manual for the engine and OD which I'll take a look at now that my curiosity has been peaked.

mk

 

[system-f]

Re: New pics added 11/25 - 86 Grumman 184 turned out to be more of a pjt than exptc

Re: New pics added 11/25 - 86 Grumman 184 turned out to be more of a pjt than exptc

Here is a site on a guy that did an OMC Cobra transom. The transom should be no more than 2-2 1/8" thick.

found out after this picture was taken that the transom was about 1/4" thinner than it needed to be. For both Mercruiser and OMC stern drives you need 2 to 2 & 1/8" between the inner transom plate and the external gimbal housing or you risk bottoming the driveshaft out in the engine coupler. That's a bad thing. The fix is to glass on a piece of 1/4" plywood to the inside of the transom. This might seem like a "quick fix" but it's quite normal, and just like the factory did it in my boat. If you put one of these in, make sure your inner transom plate doesn't hang over the edges before cutting the wood.

http://transomfix.dcpolk.com/Home-1/installing-the-new-transom

Like you said, I don't know how much of a difference 1/4" is going to make on spline engagement, but this guy made his transom too thin and added another piece of plywood on the inside to make it thicker.

 

[mikezohsix]

Re: New pics added 11/25 - 86 Grumman 184 turned out to be more of a pjt than exptc

Re: New pics added 11/25 - 86 Grumman 184 turned out to be more of a pjt than exptc

S-F , thanks for the reply and link.

I did look thru the factory manual because I started thinking too much about it, and didn't find anything.

It's good to know that the issue was the transom was too thin, not too thick. Bottoming out the spline is an obvious no-no.

From what you've said, I should be fine.

Thanks for the help!

mk

 

[mikezohsix]

Re: New pics added 11/30 - 86 Grumman 184 turned out to be more of a pjt than exptc

aah, the floors (decks), what else could be a problem?

I had a "down" day on the boat this past weekend waiting for everything to fully cure before I put the transom in and put the motor back in.

Thought I'd take a look at the seams towards the front of the boat because I'm going to apply Gluvit on all the seams (yes, I do listen Bob). When I pulled the carpet/fabric glued to the hull back forward of the helm I saw a live carpenter ant. WTF? You gotta be kidding me, I put every poison sold in the boat and they're still alive.

I pulled the carpet back off the forward part of the deck and it was damp. That does it, it's all coming out!

So, up came the floor sections...

There was pure mud, which was actually sawdust from the ants and probably mouse turds (yes, this boat was a regular zoo for maybe years) which plugged all the drain paths...

...and I started looking around.
The forward section in the bow, which is probably 2.5 wide x 1.5 foot fore/aft x 1 foot deep was a honey comb that I could push my hand right thru. The suckers were living on it - they were eating it! Not any more!

I broke up all the foam...

 

[mikezohsix]

Re: New pics added 11/30 - 86 Grumman 184 turned out to be more of a pjt than exptc

I took the foam and put it in a barrel and chopped it up with ice chipper for the driveway (those in the north will understand, you all down south have to guess), and broke the foam up and bagged it.

I then simple greened the hull, soaked it twice, went over it with a scotch brite pad, and then power washed it to death...

With that done, the transom went in with no trouble.
All new SS fasteners with nyloc nuts.
OD went back on
everything was sealed with 3M 4200.
(no new penetrations into the transom, all holes were drilled and sealed before installtion)
...and the motor is dropped back in place.

I have all the floors for templates so will be cutting the new decks and FG'ing them.

I have to pick carpet - any favorite vendors?

Then comes Gluvit, insulation, replace the decks...

 

[ezmobee]

Re: New pics added 11/30 - 86 Grumman 184 turned out to be more of a pjt than exptc

Nice job on the clean up.

 

[BobsGlasstream]

Re: New pics added 11/30 - 86 Grumman 184 turned out to be more of a pjt than exptc

Looks like you made quick work of that mess.
looking good now.
Bob

 

[mikezohsix]

Re: New pics added 11/30 - 86 Grumman 184 turned out to be more of a pjt than exptc

thanks for the comments....

I had a furlough day on Wednesday, and worked the rest of the weekend except half a day Thanksgiving, to get where I am.

It hasn't been bad work at all, I'm just glad it's a tinny!

 

[belairbrian]

Re: New pics added 11/30 - 86 Grumman 184 turned out to be more of a pjt than exptc

I took the foam and put it in a barrel and chopped it up with ice chipper for the driveway (those in the north will understand, you all down south have to guess), and broke the foam up and bagged it.

Since I speak northern and southern I'll translate.

Ice Chipper: A garden hoe someone forgot to bend.

 

[evildocrsx]

Re: New pics added 11/30 - 86 Grumman 184 turned out to be more of a pjt than exptc

Nice job! It turned out to be a complete restoration. At least you'll know the boat will be solid when you get done.

 

[Triton II]

Re: New pics added 11/30 - 86 Grumman 184 turned out to be more of a pjt than exptc

Great job Mikez... keep this one coming!

 

[system-f]

Re: New pics added 11/30 - 86 Grumman 184 turned out to be more of a pjt than exptc

I have to pick carpet - any favorite vendors?

Durabak or another similar coating. After seeing the water my old vinyl flooring held after 3 months no more carpet or vinyl unless it can be removed from the boat after each use.