All the (off)road going amphibious vehicles of the world. (work in progress) All the (off)road going amphibious vehicles of the world. (work in progress)

Last modified 29 March 2011

   Beneath Still Waters, there is NOISE!!!!!

My Amphib index
This part is about the Water-jet of the Dutton, Amphijeep, Commander, Mariner or what ever you call them.
What I call it ?   >>>>  A PIECE OF SHIT <<<<
jet side view
jet rear
As you can see this water jet is made from GRP
Glass Reinforced Plastic
It is connected with 4 bolts to the GRP hull. GRP is flexible!!!
There for the whole unit will move under power.

If you know the brand and type of this impeller please email me.

I mean Please, Please, Please !!!!!
jet inside
The front top half of the water jet housing IS THE HULL!

There is NO resonance (any-more) running the water-jet OUT of the water.

The water inlet hangs lose and it sides are in contact with the hull.
lose lower half
Various obstacles in the water-jet . Now removed!

I used an imitation Dremmel to grind the bumps away.
step up
top problem
hit right side
Now I can slide a piece of paper between the impeller and the wall in any position of the impeller. The opening between the impeller and the jet housing now varies between paper thickness and 5 mm.
Most interesting is the 5 mm height difference in the left photo.

The middle photo shows the rubber ridge that was hit by the impeller.

In the right photo some contact damage.
This is the belt drive between the two fuel tanks.
The water jet sits lower than the rear axle there for a step down in height
and a step up in revolutions is needed.

The resonance is moving the sides of those 2 fuel tanks and that results in a deafening noise.
2 diesel tanks
On close up I have my doubts on the balance of this belt wheel.

But that is not all.
drive belt front
top of the ......
top of the LOW

I have never seen a free floating baring, normally they have a solid base and thin metal filler plates. That has something to do with vibration e.t.c.
There is a place on Nemesis where the sun never shines. :-)

But a camera can go there.

Besides some really !$@%
workmanship they also run out of paint.
I hope to have solved the problem I removed the contact areas (impeller) from the water-jet. I also grind off the edges of the water inlet that where in contact with the hull.
Then I filed the gapes with Butyl 37 filler. That filler stays flexible "forever".

But if the water jet moves more than paper thickness the impeller will hit the wall again.

But first I have to do a test (1 Sept 2010) is the first opportunity.

I hope the noise/resonance is all most gone.
If not, well then then is more work.

Hardest thing now is that I can do a maximum of 2 hours a day then my personal batteries are down.

First I make a test in the water, if and when the vibration is not gone then
I cover the inside of the water-jet with GRAY paint then I spray it over with PURPLE paint. After a test in the water I can see the big and the small contact areas.
Filler Butyl 37

filler end result
The test drive went OK the vibrations where mostly gone The rear view mirror had a cleaner view. I can see some things in it. There was extra NOISE. I think I need to use purple paint for the last bumps.

I was making an inspection on a trailer slipway.
Started a conversation to some custom officers.
When they where gone I wanted to travel, over water, back to the place where I entered the lake.

When I tried to start the engine the BATTERY was DEAD.

I am a member of the Dutch auto-mobile club, with in 45 minutes a mechanic showed up with BIG starter cables.

Anyway when Nemesis was running again I was heading home over road.
It looks like 1 cell of the battery short circuited,
Now I have to borrow the battery from Sam Diesel.

When the battery was placed I jacked up Nemesis to look at the water-jet.

The Butyl 37 filler was completely gone but the resonance noise was not that bad considering what is was before.

So I increased the gaps on the water inlet. That way sound waves can not go direct into the hull through the sides next to the water-jet.
Sounds is what makes the fuel tanks vibrate.

I used the purple paint.

OK, I thought is was purple but it is not.
But looking at it is as bad for the eyes as purple paint. ;-)

Next test is on 11 Sept 2010.

Bigger gap

purple paint
I also made a hand throttle. That is more relaxing on the water

Bend the clutch peddle to the right so I can put my left feed at rest at the left of that peddle. Just like any "normal" car. ;-)
Down side is that I have to drive without shoes from now on.
The peddles are to close for my size 44 workman's boots.

Made a modification that keeps the windows in place.

On the water when I'm standing in the open roof I can lean on the window it feels solid now.
window old situation

window new situation
When on the road at 90 km/h I can communicate with the passengers with a slightly raised voice.

But on the water at a speed of 5 km/h I still have to shout very HARD.

The top speed (on water) is 7.5 km/h but I need hearing protection at that speed, not from the engine noise that is running at 2200 revs (3 Th gear)
It is the water-jet that rattles with a very irritating sharp noise.
after purple
It clearly shows in the photo's there is contact damage in the paint.

On those spots I have to do a bit of grinding. then test drive Nemesis again.

If and when that gives no real improvement, I have to think drastic.
That means a rebuild to propeller or to a real water-jet.
But for both solutions I have to remove the fuel tanks because there is not enough space between them.

But the tanks do not fit easy through the hole where the photo is taken.
But what was I expecting, it is a Dutton and it will stay a Dutton forever.

The test was on 20 Sept 2010 and the weather was fear.

The loud ticking sound from the water-jet was much reduced,
later inspection showed 2 small contact area that is now fixed.

The HARD TRRR sound, base snare drum like, from the fuel tanks was NOT gone.

after purple

fuel tanks
The time it was raining I used to find a 2 litre/hour leak.

On the right and the left sides there are drain plugs and the left one had a bit of water every time I went swimming.

The leak was not one of many bolts that stick trough the hull, it was simply the lack of filler as can be seen in the top photo.

In the middle photo I used Butyl 37 filler in a way the filler runs out under the step.

In the bottom photo I cleaned the excessive filler
and in the future I will paint it black except the bottom part it will look nice.

I tested on 22 Sept 2010

Did try some things out in the dark, smelly and small back.
First I tried to find out if the resonance is on the X, Y or Z axle.
Working blind to find resonance normally makes things worse.

Al experiments to find the direction of the resonance where futile.
step 1

step 2

step 3
I removed the rudder there is now a little more top speed (7.8 km/h)
and a little less noise. I can steer with the front wheels.

I experimented with the belt drive tension. That does change the sound of the resonance a little bit.

There for I'm very sure that the free floating baring is the source of the resonance. But how to make a 100% fix, I do not have a clue!

Starhyke mode on/

First I will sample the Scottish bottle and find out if brown chocolate tastes better than white chocolate

For that I take 4 weeks then there will be up dates on this site again.

At least that was the plan, I still had a bit a surgery coming
so now my right hand is recovering.

The plan is to lift the tanks and isolate them from the hull.
It is highly unlikely that the vibration travels through the air.

In the mean time I go on with the planing of the upgrade of the suspension.
See the next page "Calmer Water 01"

I did not want to make a new High Water page!
I do not want more High Water pages!!!

Lifting the tanks sounds so easy. ;-)
November 2010
One thing was clear from the start the tanks are to big to fit through the opening behind the rear seat.      So I expected a 2 day job.     What did I now. ;-)

To turn the tank on it side a M 8 stud was in the way.
With the tank out of the way you can now see it was mounted Dutton style.

To go there where no spanner has gone before.
The tank is to close to the stud for fingers or spanner.
I cut an old spanner and welded a stud to it to get an L shape.

I think I will be a fine gynaecologists, I just need a bit of practice. :-)
Fuel tank stud
This is the bottom of the left tank turned front to back and on it's side.

That was on the 4Th day!
Besides a low personal energy level, my recently reconstructed chest does not like to be in contact with any hard surface.

I remembered words now I thought I was long forgotten. ;-)
Tank max out of the opening
All that work paid off.

With a view like that only SILENCE is fit.

But I do want to mention the spare parts that came free with the car.
(Right side of the rotten wood)
Fix one fined 2 more:

1 - The hand brake cable is rubbing on the drive shaft.
2 - The rubber tubes are water hoses and there for not oil resisted.

3 - Nothing new, but when I fill the tanks, one tank is spilling diesel through the air in/out let when tank number 2 is only half full.
So I will use cool-filters to keep the diesel in.
hand brake cable
First clean that dirt.
Then remove the many glass fibres that stick out of the wall.
Then I paint to protect the glass fibber hull.

A friend asked me why Tim did not used GRP protection.
My answer was I can NOT say he does NOT.
But to say that he USES GRP protection is an overstatement. ;-)
painted room
Build two new bases for the tanks.

OK, one at the time. The trick is to get it almost level.
Almost level means that all the fuel in this tank runs back to the first tank.
The front of this tank is now lower than the rear.

Between the hull and the tank base I will put isolation foam.
New tank base
The work is a bit hard, not only because I have a few little medical problems.
But mostly because the work space is small.

On the right side of the photo you can see the fuel tank half out of the way. :-)

If I stick my head in to deep I will never get out on my own power.
narrow work space
That almost happened when I put in the weights to keep the new floor down when I filed the space under the new floor with foam filler.

It is now 1 December 2010 and I took Nemesis out of the road tax,
so I can not make a test drive in the next 3 months. This saves 300 Euro.
When I change my mind I have to pay extra tax above the normal tax over those 3 months.
I think tax is a Dutch invention we have so many of them. ;-)

Do anybody knows of a county that has change your mind tax?
Pur filler
I cut away the execs foam and gave it some paint with an extreme long brush.
Fuel tank with foam
On the base I put a sound isolation blanket.

I removed the blanked to put the tank back in with the left tank sticking half out.
that way I was able to do all that work again for the second tank.

Because that tank has the fuel filler hole and the fuel in and out to the engine.....
Well I can say I used many words not to be used in the presents of children. ;-)

After I fined this part I noticed that this type of isolation absorbs water under vibration!
At the start of January 2011 I changed the isolation for a water and diesel proof type.
And I worked in almost silence. ;-)
fuel tank isolation

Both tanks are in there place but still need to be filled.

Then I will start the engine that is standing still for 2 months and drink a beer.

OK, from behind you look a horse in the ...... :-)
fuel tank new mouning
Still need to place the cool filter.

I will use only one because they cost 70 Euro and I think that 2 filters
do not solve the problem of the second tank not being 100% full when the first one is.

But one filter will stop the fuel from running out of the air let-out in to the street.
fuel tanks over view
I have made a fix the hand brake cable that is running over the prop shaft.
This is what I call a temporary solution.

But I have learned that nothing in this world is more permanent than a temporally solution.
Hand brake temp solv
On 7 January I started to fill the tanks (a bit) and I started the engine again.

That was fun:
After the first 8 litre I got only air but no diesel at the engine.
With 12 litre in the tank there was pure diesel and the engine started and was running OK.

The fuel gauge came out of his rest with 20 litre and at the empty mark with 25 litre.
And with 60 litre in the tank the gauge reads 1/4 full  !!!!

OK MORE WORK TO BE DONE (21  February 2010)

The tanks are 35 cm high, 50 long and (25 x 35)/2 wide
that is 35 x 55 x 30 = 52,5 litre times 2 makes a 100 litre fuel

To make a long story short I bend the fuel level sensor that 60 litre shows over 50% level

On the right there is a photo of the cool filter.
At the left of the filler pipe you can see at the same height the air outlet.
Because you fill the first tank and that tank runs over in the second tank.
The first tank is full when the second tank is NOT!
It is no wonder that the diesel was running into the street when filling the tanks.
Cool filter
Besides filling in some details I think I can close this chapter. ( 5 January 2011)

update 22 March 2011:
The test was O.K. the fuel tank noise is gone.
I think the drive-shaft to the water jet is bend that still gives to much vibration and noise but the fuel tank drums are silent now and that is a very good thing.

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Only to my neck in the shit.