Tri-hull Lund 315 Guide Series restoration

[Buster.here.wants.to.fish]

Howdy folks!

Anyone else working on an old Lund 315 guide series? Mine is a 1979 Guide deluxe I believe. It was given to me after the previous owner had it in storage for a number of years. It used to belong to Marv Koep and I believe it was his first guide boat. I still need to check, but I believe the Lawrence still has his GPS locations. Needless to say, the boat has a lot of history and it would be a shame to retire it...but I wonder if that is what I should do?

I've had it out once and it rides like a dream...except for the loud breaking sound and the transom bowing like crazy. I limped it back to the launch and won't be taking it out until I know it is safe.

Here is what I know is wrong (as of now):
- The transom is rotten (big crack as well)
- The floor is rotten (at least in the back)
- My previous experience working on boats.

Here is what is not wrong:
- The motor! Started on the second pull after being in storage for years! Johnson 25 HP 1991 vintage
- The electronics are old but work
- My naive enthusiasm and desire to learn new skills

So...I'll be replacing at least the transom and the floor. Who knows about the stringers! My plan is to replace the transom from the inside so I can tie it in with the stringers. The wood under the fiberglass floor is a wet soggy mess, so I'll have to replace that.

Here are my questions:
- Am I nuts for attempting this?
- Should I totally redo the floor or should I try to re-use the fiberglass that I cut out (replacing the wood, obviously)
- How does one seal both sides of the wood for the floor and attach it to the stringers?


Thanks!

Ted

 

[Redtruck12]

Welcome to the boat restoration family
looks like a nice old boat and sounds like you really like it.
the wood under the decking is stringers I would think.
this is a fibreglass hull?
from your pictures you’re looking at a full gut and restoration and if so you have come to right place for advice.
take some time and read through the sticky’s at the top of this forum- toms of great information to get you up to speed on what you’re getting into.

 

[gm280]

While it may sound shocking, I also agree to gut the entire hull and start from scratch. Not as much involved as you may think. And YES the stringers are also toast if the transom and floor is rotted. But that is expected and the usual issues with most every rebuild boat project on these forums.

I did basically that exact same thing with an old (1976 Tom Boy boat) if you care to read through my project linked below. I will say this, once you do get it gutted and rebuilt, it will outlast what the factory did by years... JMHO

 

[sphelps]

Welcome aboard !
‘There’s nothing on the boat that you can’t fix ! That’s if you don’t mind a little effort ,money , and a good bit of itch . :lol:
Make sure to get the proper PPE . A good respirator is a must for the fiberglass grinding needed..

 

[Buster.here.wants.to.fish]

Thanks for the advice everyone! I am all set up with a good respirator, shop vac, and a good selection of cutting and grinding tools. I already got the old seats out and opened up the floor. Unfortunately, I picked the exact WRONG place to cut and ended up gutting about a 3" cut in the hull and took out a piece about the size of a quarter. Good thing I see this whole thing as a learning experience.

My plan for that spot is to do an inside and outside job. I'll grind out a bevel on the inside, fill the actual cut with some Peanut butter, then layer up cloth with epoxy. Does this seem right?

Should I do the same on the outside? Is it ok to use epoxy on the outside or do most people use poly? (I might want to gel coat it later).

 

[Redtruck12]

If you’re going to gel coat you cannot go epoxy they “don’t like each other”
sounds like you’re on the right track.
i would go polyester and 1708 - no need for PB until you’re faring it smooth.
how are you supporting your hull? Fiberglas hulls are very weak and will easily crack or distort without adequate support and bracing.

 

[sphelps]

OMG ! You cut through the hull by mistake! That never happens ! :lol:
Yeah redtruck is correct epoxy sticks to poly but poly don’t stick as well to epoxy and gell coat is poly based ..
A few layers inside and out and you’ll be good to go ...

 

[Buster.here.wants.to.fish]

Yesterday I opened up floor. As expected, there was a lot of rot. What I didn't expect was how much water was in there! The foam was a sponge that probable held over 50-100 lbs of water. I can now lift the back of my boat it is so light! The shovel came in handy to get it out of there.

Glassing is still a long ways off, but I have two questions:

1. Can I use poly for most of this? Epoxy is crazy expensive and I have access to good poly. (planning on epoxy for between transom laminates.)

2. What is your opinion on replacing the foam with closed cell foam? Do most folks foam between stringers?

Thanks!

 

[Redtruck12]

Poly is perfectly fine for all you will need to do. No need for epoxy.
most go with a good glue that is water safe between plywood layers on the transom and thickened poly resin (aka peanut butter) to bond the transom to the hull.
yes closed cell foam / flotation foam is required. Really good for stiffening everything up and reduces noise as well.
NOT the same as the stuff you get at the hardware store. Pour in 2 part flotation foam from a reputable supplier.
good progress on the gutting

 

[gm280]

From the pictures you posted, you are looking at every other boat project as they started out. Congratulation. You have the exact same rot that so many others have posted. So you are right on par with your project.

Forget the epoxy. All you will need is polyester and MEKP. Of course the CSM and 1708 fiberglass clothes as well. But that is down the road some from where you presently are. Once you gutted out the hull, time for the really fun stuff. GRINDING out the old fiberglass.

Most use angle grinders with 36, 40, 60, or even 80 grit flapper disks. The more aggressive the grit, the faster it goes, but also leaves a rougher finish. So pick your grit. Personally I used 60 grit. But others like the 36 and 40 grit. Either way, you have to protect yourself with a Tyvek full suit and absolutely a 3M face mask with disposable cartridges. Don't breath in that fiberglass dust if you really want to use the boat after it is finished.

And what you are going to try and do is grind out all the old fiberglass and leave a pretty much smooth area to install new stringers and such. But whatever you do DON"T grind through the hull. If you do that, you are seriously in for some real problems...

Okay, don't worry, seems everybody grinds through in multiple places. But it is so easy to repair so try not to do it., but understand you problem will. The repair is basically easy to glass over and fair out. That is the real beauty of fiberglass hulls.

Post your progress and ask questions. We all are here to help out!

 

[Buster.here.wants.to.fish]

Anyone ever use a pressure washer to clean it up a bit prior to grinding?

 

[Redtruck12]

Can’t hurt much if it’s gutted

 

[Buster.here.wants.to.fish]

Last summer I got the heavy grinding done. I ended up making a plastic tent in the garage after seeing how much dust there was. Several hours with a shop vac later and the garage still has a lot of fiber dust in the rafters. I hate grinding. One tip...those shop vac bags are spendy, but between that and a muffler, clean up went a lot easier (no cloud of glass dust when emptying and the exhaust doesn’t kick up more dust). Should have started with all of this...but I’m kinda dumb sometimes.

i found that everything except the original benches was not glasses in. It looked like construction adhesive and it must have worked for a while. I’ll be glassing everything. I plan on adding new longer benches and a casting deck. Under the deck I’ll have areas to slide in two gas tanks. I might add a door (port?) for under deck storage.

As I’m planning, any thoughts on layout? I’m thinking the two batteries in back opposite the driver, tanks up front, no live well (cooler), and an area for a bait cooler next to the driver. I’ll update pics later.
Ted

 

[Bait Drowner]

I've a 1980 Guide 315 that's been used sparingly during the summer and kept indoors over the winter. After a heavy thunderstorm this summer, I found a piece of waterlogged wood in the bilge that looks like part of a stringer. Floor and transom seem solid. Been watching Buster here's project with interest. I don't have the space nor experience, and at 75 years young I am wondering if I'm the one to do the necessary repair/restore on my boat. Anyone have any idea where and at what cost I could find someone else to do the work in the greater Chicago/Milwaukee area?

 

[Buster.here.wants.to.fish]

Resurrecting this old post. I realized I never posted the finished project! I've been making some great memories with this boat the past few years. I got pretty good at doing fiberglass and learned a bunch. What I have now is a solid little boat that works great for what I need!
Here is what I did:

• Took out absolutely everything except the outside hull
• Used 40 grit with an adapter on a buffing tool. Slower than a grinder so it doesn't melt stuff and super aggressive. Removed all of the old glue, gunk and god-knows what to get it down to raw fiberglass or at least really roughed up gel coat.
• Clean clean clean...then cleaned. Then wiped with acetone.
• Built the transom (all lumber was marine plywood from a boat repair shop...not the cheap **** at Menards). Clamped the **** out of it.
• Realized I had pockets of air in transom because I'm an idiot who did a major glass job in 90 degree weather. Drilled holes and injected slightly thickened two-part poly to fill all of the gaps. 97% confident I got them all and 100% confident it is 500% better than the last transom.
• Built stringer down the middle. Used a bunch of random stuff I had to weight it down.
• Said all of the swear words when I realized that I was an idiot and used a full (and very leaky) gas tank for a weight and it leaked all over the bottom of the boat. Wiped it up the best I could, said a prayer and kept rolling.
• Built a deck, then used two part marine foam to pour into below deck as well as a small area at the front of the boat. glassed the holes.
• Built a casting deck and glassed it. Then installed and glassed it in place.
• Built benches at the back that are fully glassed and provide hull integrity.
• Installed hatches in front.
• Gel coated inside.
• A buddy helped built the bench seats and custom sewed the vinyl.
• Made some mahogany thingies on the back to attach stuff to.
• Did a bunch of wiring - bilge pump, lights, navigation, fish finder, USB charger, horn.
• Got new gas tanks, hose, and some fittings.
• Realized the gel coat was tacky so repainted the entire inside with good topside paint.
• Painted the outer hull with tractor paint from fleet farm. It works. sort of.
• Fished a bunch.

 

[Buster.here.wants.to.fish]

Some photos from when I was working on it.

 

[Baylinerchuck]

That’s a nice fishing boat!! Great job!

 

[DeepCMark58A]

I am sorry I have a bias against lund fiberglass trihulls of that era. Lund bought the Shell Lake boat company to delve into the fiberglass boat business and killed a business and ended boats being made in Shell Lake WI. May not be rational but it is what it is.

 

[Wildey]

I love it when a plan comes together ..... just like Hannibal !
Good job !