Question about a Avon Searider Water chamber

[avonnj]

Hi group I had a avon searider sr4 deluxe about 35 years ago. The water chamber on that model would let the water flow from the front of the boat to the back of the boat while resting, then the water would exit out of the back when it comes up on plane.
The question i have is when I looked inside the rear 4" opening inside the hull I saw foam blocks that looked like what takeout coffee cups are made of.

Did Avon ever enclose those blocks of foam with fiberglass in the later years?

Next Question is how do you clean out that compartment with marine growth? (Barnacles, Mussels, Zebra Mussels)

I was thinking of buying another avon searider that was left in the water all year long for a few years.

I was thinking of using a pressure washer thru the rear 4" hole, but if the same foam blocks are their they will get destroy by the pressure washer.

Then I was thinking of filling the compartment with a liquid after blocking the exit holes with a plug. Something like Barnacle Buster letting it sit for a day or two then flushing it out clean with water. I worry that the liquid may destroy the foam blocks. But if the blocks where cover with fiberglass then that would not be a problem.

Does anybody on here have an idea how to clean out this chamber

[Tim M]

Not sure about the older ones (35 years really is an early model) but certainly the later ones didn't have foam, they had an enclosed fibreglass moulding under the deck which acted as a buoyancy chamber in the area that floods. (I took the deck off a 4m Searider once and saw it all first hand). Perhaps before they did this they used foam.

I wouldn't imagine Barnacle Buster would affect the foam. Easiest way is to spray a little on to double check. I think your idea of getting some in there and leaving it for a while would work. Likewise a pressure washer if you can keep it away from the foam.

[avonnj]

Hi Tim: Thanks for the reply. What year was yours? I'm looking at a 5.7 avon searider and from my old one many years ago I was worry about the foam disintegrating when hit with a pressure washer.
My avon had to be around a 1975. and I saw the foam when you looked into the 4" hole and the barnacles stuck to it. Do you think a 2001 would have a fiberglass enclosure to protect the floatation? Then If the hull has marine growth in it I should be able to blast it clean with a laser nozzle pressure washer by inserting it into the 4" exit hole on the transom. I'm thinking maybe a 12' long metal tube for the pressure washer.
One last question was their a clear run from the stern to the bow if I ran a rod in their?
Or did the floatation blocks blocked the way?

Thanks for your help

[Tim M]

It'll be a 5.4 if it's a Searider - there is no 5.7

A 2001 will certainly have fibreglass buoyancy compartment under the deck. I have a 1999 and it has this. As far as I can recall, the buoyancy chamber is fitted on the underside of the deck - there is a clear space under it on top of the inside of the hull so in theory yes, you should be able to push something all the way through. If you shine a light in the hole at the back you should be able to see quite a lot.

Of course, the foam that you refer to could be something someone has added at some point.

[beamishken]

If you do go for pouring in a chemical to dissolve the growth,dont waste your money on barnacle buster.The main ingredient in barnacle buster is hydrochloric acid. Buy Brick acid from ebay it does the same thing just doesnt carry the marine premium you can also get a stronger concentration which you can dilute yourself if required
https://rover.ebay.com/rover/0/0/0?m...2F112445267234

[avonnj]

Hi Tim & Beamishken: Thanks for your help. If this deal works out with the avon I'll be posting photos here of the process.
Knowing that it's fiberglass on the inside helps me out a lot.

Tim the foam blocks in my old avon where 24" across 6" thick and about 4' long in depth. The floor was never cut open. So avon had to put them in their.
I'll never forget what I saw. Green slim and white covered blocks with many barnacles stuck to it. When I poke at it the foam dented easy.

Again thanks for your help.