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

[mikezohsix]

I was looking for a cheap tin boat to knock around with at camp and not use my 210 Sea Ray bowrider every time we went from the island to the main land.

I found a 86 Grumman that hadn't been in the water since 1990 and decided to make a project of it.

Got it running, power washed 20 years of mouse out of it, cleaned the muck out of the gas tank, replace fuel line front to back, replace shift cable and out drive bellows, and decided to tackle the corrosion in the sides of the hull near the transom. Shown here...

port side

stbd side

After pulling the top of the transom I started working on the two corners. The corners were foamed in place so I cut as deep as a long blade on my sawsall and then started breaking out the foam in each corner.

What I found is in the next post.

 

[mikezohsix]

new pix added 4/6/10 86 Grumman 184 w an I/o - more of a project than expected

new pix added 4/6/10 86 Grumman 184 w an I/o - more of a project than expected

I sliced and diced my way thru the foam

and found this on the port side, those are carpenter ants, now dead.
Note that the transom is perfect in every spot except where the foam was up against it. Never would have bought the boat if I'd known what I was getting into

stbd side

 

[mikezohsix]

Re: my 86 Grumman 184 w an I/o just turned out to be more of a project than expected

Re: my 86 Grumman 184 w an I/o just turned out to be more of a project than expected

I'm in too deep to quit at this point, so...

I checked the transom every where visabile and it was perfect.
Note three layers of 3/4 5 ply, and it's dry and clean looking.

I think the transom is too far gone, can't really tell how much is soft, so I'm going to replace it.

Tomorrow the outdrive comes off (again), and I'm pulling the motor. Then the inner and out upper OD assys, never did this before but seems straight forward.

Then some thru transom fasteners, and the wood comes out.

So then what?

Gluvit on the corroded aluminum.
What do I do for patching inside and outside on the thru corrosion?

Can I glass over the corroded aluminum or will it not stick because of the flex?
Can I glass with Gluvit?

I read about transoms and coatings so will just follow what others have done with a resin coated transom, but not until the aluminum issues are done forever.

I wasn't sure about poured in place foam, now I am, never again. I'm going with flat sheets when she goes back together.

Comments and thoughts welcome as this is the first time I've gotten myself into this kind of mess.....

 

[ezmobee]

Re: my 86 Grumman 184 w an I/o just turned out to be more of a project than expected

Re: my 86 Grumman 184 w an I/o just turned out to be more of a project than expected

Nice looking boat. That foam sure did a number on that transom. Bummer because otherwise it's the nicest transom I've seen in an older boat! It doesn't look like they sealed it though which was the problem. I'm FAR from and expert but I think I'd just Gluvit or JB Weld the heck out of your corrosion spots from the inside. Maybe fair a little JB on the outiside. Good luck with your project.

 

[mikezohsix]

Re: my 86 Grumman 184 w an I/o just turned out to be more of a project than expected

Re: my 86 Grumman 184 w an I/o just turned out to be more of a project than expected

Engine is out,
Outdrive inner and outer is off.
Not too bad at all.

Pulled all the thru fasterners for the transom and any odd screw here or there for depth finder brackets etc.

Had to strap the boat to the trailer and then put a pipe on a floor jack in the OD opening and jacked the whole thing off the ground. In about 15 minutes it started to give and once it moved, I was on the way to pulling the carpenter ant home (transom) out.

Here's what I found:

stbd side where the hole was from the outside

looking at the transom

looking aft

looking sideways

port side
transom is on the left, the bracket that clamped the transom wood is on the right

 

[mikezohsix]

Re: my 86 Grumman 184 w an I/o just turned out to be more of a project than expected

Re: my 86 Grumman 184 w an I/o just turned out to be more of a project than expected

here are pictures of the transom wood

from the inside

from the aluminum/outside

 

[mikezohsix]

Re: my 86 Grumman 184 w an I/o just turned out to be more of a project than expected

Re: my 86 Grumman 184 w an I/o just turned out to be more of a project than expected

I need some help here to see if I'm on the right track!

I'm thinking pull the two right angle brackets off the sides that clamped the transom.

Clean up the aluminum with a stainless wire brush on a die grinder.
Alodine the area.

Gluvit every thing.

Bond a piece of aluminum over the correded area, over the rivets, formed as best I can with 3m 5200

Put it back together, may be with a small patch on the outside.

Thoughts??????

 

[BobsGlasstream]

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

Hello mikezohsix,
In spite of the problems, it looks like a nice boat.
I agree with ezmobee, That transom doesn't look like it was ever sealed.
The good news is that you have enough of it to use as a good template.
I don't think you would have had that much damage if the transom would have been properly sealed.
Good luck with the project.
Bob

 

[LX Kid]

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

You've really got your hands full on this project! Great looking boat and well worth restoreing. The transom looks like it will be the less problem to deal with. The aluminum, on the other hand, may take a little more work to get the corrosion stopped and a new skin on it. I'm sure there is a lot of talent here that will be able to advise you. To me it seems all the corrosion will have to be cut out/off in order to stop it. I may be wrong but I'm sure there will be others that can enlighten both of us. Sure do like all the pictures you have been posting. They really help us to see what's going on with your project. Good luck.

 

[jonesg]

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

I would preferably see about having the alum tigged with a patch.

Thats called crevice corrosion, alum is great until water is trapped like that.

Either way you go about fixin the hull I wouldn't do that sort of foam again, maybe loose foam.

 

[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

I would preferably see about having the alum tigged with a patch.

Thats called crevice corrosion, alum is great until water is trapped like that.

Either way you go about fixin the hull I wouldn't do that sort of foam again, maybe loose foam.

I thought that it was a no no to weld near the seams because of the sealer in between the layers.

I was really hoping to patch it with some type of adhesive.

 

[Andy in NY]

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

once you have that new transom in you will not regret it. that thing will outlast you...

 

[mikastorm]

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

Do a search, I saw somewhere on here where a patch was done by a welder and it turned out great. I would not try to patch that with any bondo.
You get that fixed and that will be an awsome boat. Good luck.

 

[Bob_VT]

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

That corroded area is NOT a stress point. That appears to be salt water corrosion.

Here is the solution..... You can lay a piece of aluminum in there and attach it with just a simple pop rivet or two...... HOWEVER I would first sand the existing corrosion and coat with gluvit..... multiple coats with a wet coat prior to installing the patch..... rivet it in and hit the seams and entire are with gluvit again.

I would take the opportunity to use gluvit on all the rivets and seams.... it acts as a fantastic barrier coating for aluminum (as long as it is not in direct sunlight) but does not have any UV properties.... exposed spots should be painted after it is used.

You could have a patch installed by a welder but I would still do the gluvit.

It has been said above and the new transom will far outlast the old one.... but DO NOT use pressure treated plywood and good quality exterior plywood will serve the purpose just fine.

When you re-install flotation we basically recommend blue/pink board from a building supply house and you will probably need to build it up since it usually comes in 2" thick sheets.

 

[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

That corroded area is NOT a stress point. That appears to be salt water corrosion.

Here is the solution..... You can lay a piece of aluminum in there and attach it with just a simple pop rivet or two...... HOWEVER I would first sand the existing corrosion and coat with gluvit..... multiple coats with a wet coat prior to installing the patch..... rivet it in and hit the seams and entire are with gluvit again.

I.

I thought Gluvit was thin. Would/could I thicken it with something, because the surface isn't flat?

I think I need something with more body to bond in the patch. 3M5200 comes to mind, but reading their tech specs it doesn't seem like the recommend it for bonding Al to Al. I have an email into them but they haven't responded yet.

What I'm waiting for now is what to bond the patch with and am very willing to listen to all suggestions.

 

[Andy in NY]

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

I thought Gluvit was thin. Would/could I thicken it with something, because the surface isn't flat?

I think I need something with more body to bond in the patch. 3M5200 comes to mind, but reading their tech specs it doesn't seem like the recommend it for bonding Al to Al. I have an email into them but they haven't responded yet.

What I'm waiting for now is what to bond the patch with and am very willing to listen to all suggestions.

the gluvit will be somewhat thick, about the same consistency of any other resin.

i wouldn't rely solely on it for the bonding though. hit it with a few closed end rivets.

 

[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

I finally got to a tech consultant at 3M - use a phone, forget email.

They said 5200 would be fine.

I asked if the 5200 properties would be better if I coated the surfaces with epoxy first (Gluvit), and at first didn't get an answer, but after asking more questions, it was recommended to coat with epoxy first, then bond the doubler in place with 5200.

 

[vegasphotoman]

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

wow COOl Grumman.....dont they make miltary products such as jets and such? wonder if the 2 are related...anyways

seal the new transom wood on all sides / top and bottom / merc opening / frt and back....keep the boat covered with waterproof cover or indoors, and it should be solid for 20 years easy

That is a real nice boat....now you will know it inside and out.....

good job on the work...its worth it...as long as you use it when your done!

 

[Huron Angler]

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

Nice Grumman you found there, she'll be a great knockaround rig for ya when you're all done. Great work so far, some challenges for sure, but you seem to be up for it

wow COOl Grumman.....dont they make miltary products such as jets and such? wonder if the 2 are related

They were at one time the same company that made the aircraft Vegas. Known for tough, well-built canoes and aluminum boats I'vebeen wanting one of their 20' aluminum "war canoes" for a while now, they hold like 1200lbs fully laden.

Interestingly enough my 12' AeroCraft was a post WWII boat manufacturer that switched from planes to boats after D-day as well

This is from the new company's website, Marathon boats...

In the summer of 1944, after portaging a heavy wood and canvas canoe on a fishing trip in the Adirondack Mountains, William Hoffman, Vice President of Grumman Aircraft Engineering, had an idea: What about making a canoe from the same lightweight, stretch-formed aluminum that Grumman had used to become the single largest producer of carrier-based fighter planes during World War II?

http://www.marathonboat.com/

 

[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

The last week was just on figuring out what I was going to do.

I really appreciate all the advice I've gotten in this and another thread.

I have to take the angle brackets off either side of the boat that was used for through bolting the transom in place. I've been dragging my feet because one rivet on each side is below the water line.

I got some very fine sand and a pressurized sand blaster.
I'm going to sand blast the bad areas, then alodine to prevent further corrosion.

Small doublers or patches are going to fit and then bonded in place with
3M 5200 after preping the area with 3m scotch weld primer. Then the doublers go in with a couple of rivets.

5200 comes in fast dry and regular. Regular has almost twice the strength than fast dry but takes forever to set up. The 3M rep says 7 days at 70 degrees and 50% humidity. That means it's in the garage, with the heat on and a humidifier for a week.

The balance of the raw alum gets coated with Gluvit.

After looking at the crappy lumber at the two big box stores I went to my local lumber yard and bought three sheets of 7 ply 3/4 AC (that was beautiful) for the transom and two sheets of 1/2 5 ply for the back floors.
I also picked up some PL to laminate the transom.

Epoxy goes on order to coat the transom and floor pieces along with some CSM.

I want to put the engine back in over thanksgiving, but not sure I'm going to make it....