1979 Larson Tri-Hull - Now a what to look for list

[1NewBoatGuy]

Re: 1979 Larson Tri-Hull - Now a what to look for list

Needless to say I am happy with what I have. If I had a new boat, I don't think I could enjoy it as much with nothing to work on.

Check it out, didn't realize it.
This is my 50th post, I am now a Seaman.... :lol:

 

[1NewBoatGuy]

Re: 1979 Larson Tri-Hull - Now a what to look for list

Today and yesterday I got some more work done. Replaced the fish finder, cleaned up the wiring under the dash, added a voltage gauge, rewired the battery isolator so it actually cuts all the power to the boat when switched off, finally today I replaced the bushings for the shifting arm. I now have reverse working, yippee...
So far a productive week.

 

[1NewBoatGuy]

Re: 1979 Larson Tri-Hull - Now a what to look for list

Here is something funny,the boat did not hit 58mph, (more like 58kph). A little conversion and that comes out to be about 37mph. That makes much more sense. Also another good example of why not to trust the dash speedo (it read about 55mph). Oh well, I was surprised to see it but it definitely didn't feel like it. I had to teach my son the difference between KPH and MPH the other day, now he knows.. HE HE HE...

 

[sphelps]

Re: 1979 Larson Tri-Hull - Now a what to look for list

Sounds like you got a good deal ! I would say keep it and use it . If the Admiral is happy everyone is happy !
When you said it ran 58 mph my jaw about hit the floor .. :jaw: Not to say it could not happen but it did seem quite fast . LOL!
Have fun and enjoy ! SP ...

 

[1NewBoatGuy]

Re: 1979 Larson Tri-Hull - Now a what to look for list

Sounds like you got a good deal ! I would say keep it and use it . If the Admiral is happy everyone is happy !
When you said it ran 58 mph my jaw about hit the floor .. :jaw: Not to say it could not happen but it did seem quite fast . LOL!
Have fun and enjoy ! SP ...

After having the boat for a couple months and being able to use it now for the past few weeks. I must say, it is a keeper.

Maybe if I strap an Acme Rocket to the back I might have a chance at hitting 58mph... Now only if I can find my Acme parts catalog.

 

[1NewBoatGuy]

Re: 1979 Larson Tri-Hull - Now a what to look for list

After getting back from the lake yesterday, I decided some more work can be done. The boat is solid but needs some TLC. After all, the reason I got it right.

So I pulled out the back cushion from the bow of the boat and the seat cushion on the driver side.
Boat cushion needs new wood and maybe a new cushion (if I feel I need to spend more money for new foam).
The wood is rotted on both.
The seat cushion fell off the hinges yesterday so I pulled off the vinyl, cushion and all to reveal how bad things were.
As you an see in the pic below, the wood is toast. Totally saturated in water (years old water at that) and definitely needs replacement. As for the back cushion the first pics in previous posts show that this was a definite known from the start and this upholstering project has been on the back burner for some time (since I had it).

So anyway, Next week or so I will cut out the new wood and start the replacement. As for now, it will wait. I have going balls in on this boat now for the past month or so and my bank account has dictated it needs a break.

The black is the wood, the tan is the cushion and the blue is the vinyl... The vinyl is definitely getting reused for now, the wood is not, the cushion might. Foam is seriously expensive so reusing stuff definitely is in my priorities. Plus I hate waist.

 

[pckeen]

Re: 1979 Larson Tri-Hull - Now a what to look for list

Nice fast work on this boat. You have great mechanical skills.

 

[1NewBoatGuy]

Re: 1979 Larson Tri-Hull - Now a what to look for list

Ski pylon added this weekend, this was a ton work.
The lady who had the boat before me used a "tow demon" that attached to the hooked on the back of the boat. This always makes me nervous when doing this because those hooks may rip out. They are not bolted through any wood in the transom and just are not as supported as I would like.
Anyway, a pylon is in order.
Assuring the floor had the strength it needed to support a pylon seemed like the first thing to do while planning so I knew what I was getting in to. A pylon will need serious support since it is responsible for holding on to a rope that is continuously being being jerked on from all angles. Plus towing family members and kids, I do not want injuries due to my lack of effort.
So this is what I did,

1) I built a mounting plate using a 6" x 6" x 3/4" peice of steel plate and a galvanized pipe plate. I welded the pipe plate to the steel plate. I used the two so I could know for sure the pipe would be straight and that it could be removed by just unscrewing it.

2) I then cut out a 2'x2' section of floor towards the back of the center of the boat and ran 2" x 4"s side to side under the remaining.

3) I then ran 2x4s under under the side to side 2x4s. Laid 2x4s inbetween and topped it with a 3x4" thick peice of plywood. Sealed it all up with fiberglass, foam and resin. Ensuring this is tied in to the frame of the boat I fiberglass everything with 4 layers of fiberglass to the existing fiberglass of the boat.

4) I then bolted my mounting plate on top of the plywood and trough the 2x4's. This is a total of a little over 4 inches of wood and steel. Definitely strong enough.

5) I then foamed around all board to ensure a water tight seal (using great stuff foam). Then laid the carpet over the foam.

6) Screwed in the pylon bar made from a 1.5" x 48" galvanized pipe and attached steel pipe conduit buttresses from the pylon to the back of the boat.

7) I used 3/4" plywood as additional support on top and below the fiberglass of the boat to better distribute stress from the pulling and pushing of the buttresses to the pylon.

8) Paint, can of primer and can of chrome paint to finish it off.

PICS ATTACHED..

 

[1NewBoatGuy]

Re: 1979 Larson Tri-Hull - Now a what to look for list

Ok today I got the seat cushion fixed and the side cushion fixed in the front. The side cushion did not turn out so well since I wanted to reuse the old vinyl and it seems to have shrunk some after drying out. Oh well, it's in for now. This boat will get a full reupholster anyway one day. Just looking for more functionality now.
Took it out fishing yesterday and today and again it performed well. The starter does seem to be giving me trouble how ever. I will be checking this out soon. Not sure if its a week battery problem or a starter failing issue. Solenoid clicks, tilt trim works, everything that requires power is working as expected.
I am suspecting either brushes or the armature will need replacing in the starter. may be a whole new starter if I feel spendy... Doubt that

 

[tallcanadian]

Re: 1979 Larson Tri-Hull - Now a what to look for list

Great looking boat. It sounds like a good deal.

 

[1NewBoatGuy]

Re: 1979 Larson Tri-Hull - Now a what to look for list

1979 Larson Tri-Hul, Running Jul 28th 2013 - YouTube

Youtube video of the boat running this weekend. It will be getting some more love this weekend with new plugs and a starter rebuild. The old girl needs a little more foreplay than normal to get her started. A starter rebuild seems to be what she wants since the motor of the starter has a hard time engaging.

 

[sphelps]

Re: 1979 Larson Tri-Hull - Now a what to look for list

Nice video ! Sounds like she was running pretty good and I think your son was really enjoying himself at the helm !

 

[1NewBoatGuy]

Re: 1979 Larson Tri-Hull - Now a what to look for list

Replaced the spark plug boots and clips yesterday. Pretty easy and made a huge difference as far as starting and low idling. When first starting it had a lot of trouble with dying, now not so much. The old SP clips were not making a good contact and were giving me trouble.

Anyway problem solved. The first two Images below to show the process of replacing them.
Image 1 - Leave insulation stripped back about 1/8 inch so the wire can come in contact with the clip.
Image 2 - make sure clip prong is making contact with wires using a voltmeter. Do this by rotating the clip away from the exposed end of the wire and check for continuity.
After clip is installed on wiring, lube up the end of the boot and push the clip and wire through the wire end of the spark plug boot.
Attach to plugs and your done (do this for all cylinders).

Also looks like the starter will need some love as well. I took it apart because of starting problems and can see the brushes are clearly worn out (3rd image). Not to mention the bottom of the starter housing packed with dust. new brush kit for the starter coming soon.

 

[1NewBoatGuy]

Re: 1979 Larson Tri-Hull - Now a what to look for list

OK, update
So I got bored and sick of the boat not starting (starter not engaging) all the time.

So I pulled the starter and connected directly to a portable jump starter. It spun right up no problem
Pull the starter solenoid and connected it to the jump starter, click click (sounds like it works) checked continuity between the two power circuits (big lugs) and got nothing a few times in a row then after a few more tries I got a completed circuit. Tried again and nothing.

Bingo I got the problem nailed down to a bad solenoid.

So I fired up the old Ebay machine and ordered a solenoid. While I was at it I ordered new brushes for the starter as well. They are worn and need replacement. I flipped them over a couple of weeks ago to try to get a little more life from them, but really I just need new ones. So Total cost from ebay Brushes and Solenoid came out to about $35.00. Not bad considering everything is new and will be here in a few days.

Not ordering from ebay would have cost about $45.00. Still not bad, but again I am cheap and always look for the best deals. Arco brand solenoid and sierra brushes. Still good brands.

 

[1NewBoatGuy]

Re: 1979 Larson Tri-Hull - Now a what to look for list

Replaced the solenoid today starting problems solved. Started working with the shifter today and broke a plastic linkage in the control box.
Looks like ill be ordering more parts again... Me: I love this boat... Wife: Why do you need this now?

 

[1NewBoatGuy]

Re: 1979 Larson Tri-Hull - Now a what to look for list

Bad Linkage - Mine - Broken post and crown of post broke


Good Linkage - New One Not Purchased Yet



Linkage name
LEVER, SHIFT LOCKOUT
Not needed, locks out the shifter while in high idle or warm up so you don't jam in to gear at higher revs. Common sense will keep me from doing this. At $25.00 for a little piece of plastic I may machine my own at work. From the looks of it, I can probably repair it.

 

[1NewBoatGuy]

Re: 1979 Larson Tri-Hull - Now a what to look for list

Out with the old


In with the new




Summer is coming to close here in Wisconsin but that doesn't mean boating season is over.
So more work continued on the old Larson. I ripped out the old switch panel (previous owners bad joke of good work done) and cleaned up the wiring under behind the helm. The old switch panel was a mix of a cheap generic horn button and some radio shack toggle switches and an old cigarette lighter from an older model dodge (you know the ones with the green illuminated ring around the socket).
So this all got removed and replaced with a new switch panel and power socket.
The new switch panel I picked up off eBay for $50.00 (pricey but nice) has illuminated on indicators and back lights on the pictures that indicate the operation for each switch. Cheesy but cool at night.

The power adapter was another eBay pickup for $5.00. No pics of this just mounted on the gauge panel next above the voltage gauge.

 

[1NewBoatGuy]

Re: 1979 Larson Tri-Hull - Now a what to look for list

Last weekend I pulled the plug after being out at the lake all day and there was a few gallons of water that came out. This is a first time for this boat. So after I got back home I panicked and checked over the entire boat. I found nothing. No holes, no nothing.
So this weekend we gave it another good test (8 hours on the lake bouncing from fishing spot to fishing spot and keeping an eye on the bildge). No water at all, not a drop. I am not sure where the water came from but damn, it had me scared. I am still suspect of the live well pump (it is below the water line) since the gas tank seems to sit very close to it (nearly touching it). I am wondering if the pipe going to the pump may have cracked. This I will have to look in to further. I sure hope not.

Until next time, signing off for now.

 

[1NewBoatGuy]

Re: 1979 Larson Tri-Hull - Now a what to look for list

Over the winter I want to rebuild the power head. What more than gaskets and piston rings should I purchase. Any races or bearings I need to be aware of?

 

[1NewBoatGuy]

Re: 1979 Larson Tri-Hull - Now a what to look for list

Slapped on new LED trailer lights last night. Got sick of light bulbs popping every time the trailer hit the water. Kit came with LED tail lights and complete wiring harness from K-mart on Clearance for $30.00, damn good deal.