New Tinnie first run on the water - not all beer and skittles

[NormC]

It has taken a while, but I finally got my new tinnie on the water today for it's first run. Some issues to sort out, but perhaps not as bad as I first thought.

This is a tinnie I have set up for roof topping when we travel. It is my third and biggest 'roof topper'. I certainly can't see myself going any bigger!

It is a Sea Jay Angler 3.95, powered by a Mercury 30 HP 4 Stroke electric start, gas assisted tilt. Also fitted with 55 lb Minn Kota, home made live bait tank, and lots of other creature comforts like padded seats, removable carpeted floor, casting platform / storage area in front of front thwart, rod holders (5) rod storage (for 5 rods), glove box etc.

I bought the hull from Satisfaction Marine on the Gold Coast. I organised to pick the boat up from the Sea Jay factory in Bundaberg as I was getting a boat loader / rack built by another company in Bundaberg. I dropped into Satisfaction Marine a couple of weeks ago and paid the balance for the boat and rego. The boat was picked up in Bundaberg a few days later. The next day, Satisfaction Marine closed down and is in receivership. Lucky me. If the boat was collected from Sea Jay a day or two later, I might never have got it and would have lost my money (assuming Satisfaction had not yet paid Sea Jay). But not all good news. Although I paid Satisfaction to register the boat, they had not completed the process. After several days and a few phone calls, it became clear I would have to do this myself and pay a second time. I did this today at the local Queensland Transport office.

While waiting to sort out the rego, I did all the mods mentioned in the first para. So with boat finally set up and registered, I hit the water in the Coomera River for the first time this afternoon.

Not a happy experience. Despite the 30 HP motor on a 3.95 boat, I could not get on the plane. The motor weighs 72 KG. Plus I had a full fuel tank (25KG) and a 100AH AGM battery (36KG), the bait tank and a few other things behind the rear thwart (offset to some extent by Minn Kota up front). I moved the fuel tank forward and with a lot of effort got on the plane, but now experienced lots of porpoising. Not good.

I returned to the boat ramp to check that the trim pin was in the bottom position. It was. I then noticed a lot of water in the boat. This is not looking like the great afternoon I was planning on.

Packed up and headed home. I stripped everything out from behind the rear thwart. Firstly to reduce weight, second to check where the leak might be (I had penetrated the hull a few times during the boat set up (bolting motor on, fitting transducer bracket, fitting bracket for bilge pump for bait tank).

With the stripped down version, I headed back to the river. After launching, when I lowered the motor, I learnt on it and noticed it dropped a bit further. Mmmm, looks like the gas assist has enough pressure (when new at least) to hold the motor up a fraction against it's own weight. I left the fuel tank forward for the first run. Rope start needed as I had removed the battery. Popped up on the plane in about half a second when I hit the throttle. Moved the fuel tank to behind the rear thwart. Same thing - on the plane in an instant. Check for leaks. A small dribble from one of my penetrations that I did not seal well enough, but nothing serious.

Went for a run for 90 mins for run in and about 2 liters of water in the boat. All performing well. Being a run in, no WOT yet, but looks like it will fly.

Headed home. Resealed the leak. Refitted all the 'stuff' I had removed but by now it was almost 6.00PM. Will hit the water again tomorrow to see if the initial problem was motor not dropping fully down (ie inadvertently running with the motor trimmed up a bit first time). Hopefully that is the issue. If not, I have some rework to do. First step I suspect is to move the battery forward.

Although the 4 Stroke lacks the torque of a two stroke, the only additional weight on the back of this boat compared to my last one is the 25 KG of extra motor weight (previous was 20 HP 2 stroke). I will certainly be disappointed if after ensuring the motor is fully lowered, I don't pop up on the plane instantly.

Hopefully I'll post a happy follow up tomorrow.

Norm C

[Benno1]

holy crap Norm...i need a soothing ale after reading all that!!!...i can only imagine how you feel mate...all the ups and down...like a roller coaster!!!...im looking forward to your next write up...yes hopefully a happy one...peppered with fish piccies :D
i hope you get all the problems sorted matey :D

Mrs Benno1
Sunny

[kzrocky]

OMG, what a horrible experience. Anty chance of minimizing damage expenses by contacting manufacturers explaining your circumstances. Sea Jay and Mercury might be able to assist considering a new purchase? Good luck hope it sorts itself out.

[Angla]

Rough start but it does sound like you have what it takes to convert this to a good read with a happy ending. These things give a man something to do and improve on.

Lots O Luck

Chris

[3rd degree]

Hey Norm,

Hang in there mate everything will be fine!

Have you got a little stingray or similar atached to your motor?

If not I reckon you may find fitting one of these will help you up and planing.

They can also offer a little stability.

Cheers

Jim

[foxx510]

If it helps, our Seajay 4.15 with a 25 Honda (80kg), 25l tank at back, large battery at the back, and one person at the back planes with no problems. Still gets up no worries with 3 adults and gear. It will point to the sky a bit when solo as the balance point is shifted too far back, you need to nail it when taking off to avoid it.

[Scott Ashe]

Hi mate,

Sounds like a nice rig, hopefully you will overcome your teething problems shortly, for many years of happy boating with her.

Cheers
Scott

[Blaster Bretty]

If it helps, our Seajay 4.15 with a 25 Honda (80kg), 25l tank at back, large battery at the back, and one person at the back planes with no problems. Still gets up no worries with 3 adults and gear. It will point to the sky a bit when solo as the balance point is shifted too far back, you need to nail it when taking off to avoid it.

Im with foxy on this one, your boat should , with a 30 hp on the back, leap out of the water and rest at plane all in one motion with no speeding up to get on the plane so to speak, even with all your gear in the back or front if you want , the power to weight ratio is more than enough., one can only assume there maybe a motor height prob?? hard to say without seeing it for myself, just make sure the cav plate is level with the keel line at the tansome , this is a good starting point, they say tinnie's it should be 20mm lower and glass 20mm above that line of the keel (they say that is), personal preference will determine the exact spot.
As for the water, you can tilt the boat back on the trailer and fill her up with water and try and see where the water leaks out, some peeps use a dye for this but water should creep out the hole if there is one.

Bretty

[NormC]

Hit the water again today. Started with all the load at the back and made sure the motor went down fully against the tilt pin. It got on the plane pretty well, but there was slight porpoising. I have no doubt the boat will perform well with a second person in the boat sitting forward. But it needs to perform well with one person as well.

Since my only option to move a big weight forward is the battery, I disconnected it and put it up in front of the front thwart. The boat then popped up on the plane and ran very smooth. Slight tendency to pull to the right, but at WOT it runs true.

Headed home to work out what to do with the battery. Fortunately I use AGMs, which can be used on their side (or even upside down if you can think of a reason to do it). I built a small ply platform for under the front thwart and the battery slips under (tight fit) on it's side. I converted the cables I previously had running forward to the electric motor to being an extension of the starter cables and connected the elec direct to the battery (via 45 Amp fuse). Only problem is such a long run from the battery to the motor with no fuse. Not a big chance of problems, but I normally would not do such a long run with high current without a fuse. I guess I could try a 100 Amp fuse for safety. Fuses will generally take a current of around twice their rated blow point for a couple of seconds without blowing. Thinking about it some more, the winch on my 4WD has no fuse either.

After initial testing, I switched the run switch to off (so motor would not start) and cranked the motor for for about 20 seconds to see if the cables heat up at all. They don't.

Have not had the boat back in the water since I did the work, but I suspect I have the problem pretty much beat. Just not as convenient having the battery stuffed tight under the front thwart - but I'll live with it.

Might be a couple of days before I can do another water test. I'll let you know how it goes.

Norm C

[Chimo]

Hi Norm

Have you considered leaving the battery in its original position and using some ballast ie water in a bladder positioned in the bow to give you the balance you need?

If its potable water all to the good and you can either tip it or reposition it when theres a second body on board.

Just a thought but I'd not feel happy with my battery moved to where you have put this puppy!

Cheers
Chimo

[NormC]

I've checked the motor hight and the cav plate is about 40mm below the keel.
Spoke to the place I bought the motor (Nitro Marine, Labrador) and while they say it would be a good idea to lift the motor a bit, it will not help with getting on the plane. It will lift my top end speed and probably give better fuel economy.

I've worked out the weight I have on board. If I assume the bait tank is full, the load I've had on board so far is around 260 KG. Initially I had 244 KG (94%) on or behind the rear thwart. Given that, I don't think it all that surprising (but a bit disappointing) that a 4 stroke (with less low down torque than a 2 stroke) has to work to get up on the plane and acts like the boat is not properly balanced (slight porpoising).

Moving the battery forward still gives 80% of the load on or behind the rear thwart, and seems to have solved the problem (subject to a final water test).

I'll initially lift the motor about 40mm with a block of wood. If it performs well, I'll get a piece of 40x40 aluminum welded across the the top of the transom where the motor sits.

A combination of time and weather will determine when I can get back on the water with it.

Norm C

[Chimo]

Hi Norm

You cannot beat the affect of lifting a motor. Very effective to say the least::)

I lifted this on 5" to start with and after a few trials am down to 3" where i think I'll leave it.

A few more trial runs and i'll probably get Pedrodepacus at Burleigh to weld something up too.

Its great to be able to plane a 12ft tinny with over 100kgs load with a 2.3HP;D

Cheers
Chimo

[BrenMac]

Glad to see you have it pretty much sorted Norm.

All in all, what's your opinion of the 30Hp EFI? Happy with it?

Cheers
Brendan

[foxx510]

I would be worth lifting the motor if there is room to do so. It reduces the "leverage" if you like so any lifting of the bow is minimised which is obviously what you need here. Make sure you fuse that wire at the battery, big fuses are readily available.

[NormC]

Glad to see you have it pretty much sorted Norm.

All in all, what's your opinion of the 30Hp EFI? Happy with it?

Cheers
Brendan

Brendan, for the first half hour, I thought 'oh sh1t, what have I done (with the choice of both boat and motor). Once I had things mostly sorted, I was able to form are more considered view.

Only done about 2 hours on the water so far. Motor starts in about half a second on pushing the start button. Runs very quiet - at idle I can hardly hear it. Responds very quickly to throttle. So far it seems to be the goods.

Only thing I would like to have changed is to have power tilt. The gas assist is very good and makes it very light and easy to lift, but being a big motor, I need to get right over the back of the boat to lift it. I ruled out power tilt due to the extra weight, both on the boat and on the draw bar of the caravan when we travel.

I've converted the home made crane I lift the motor on and off with to an electric winch (small 2000 lb one designed for ATV). I was originally using the winch post from the fold up trailer, but found that without the winch post, the boat moved a bit on the trailer while I was fitting and removing the motor.

I'll be able to give a more informed report on the motor (and boat) in a couple of weeks. Once the weather clears, I'll get get out on the water a few times to give it a good run.

Norm C

[NormC]

I would be worth lifting the motor if there is room to do so. It reduces the "leverage" if you like so any lifting of the bow is minimised which is obviously what you need here. Make sure you fuse that wire at the battery, big fuses are readily available.

Yes Foxy, I do plan on putting a fuse (more likely a circuit breaker at the battery. I already have a 45 Amp fuse in line with the Minn Kota.

I've tried measuring the current draw while starting with a clamp meter. It does not measure above 50 Amps, but I suspect there is a short term surge well above that level that the meter is not registering.

The most convenient design for my use I can find is a 60 Amp manual reset circuit breaker. All circuit breakers and fuses will accept a short term surge above their rated 'blow point'. I've just got to try to work out whether the 60 Amp breaker I've found will blow during normal starting. Worst case I suppose is if I buy it and it is not big enough, I will keep it as the spare for the electric motor if that fuse ever blows.

Norm C

[bigfella23]

Norm, I have had great success with fitting the correct size Hydrofoil on the engine. I have found they have the effect of negating the weight of the 4 stroke, battery ect.
I would'nt be without it.
Bigfella23