"New" 498 Hobby very heavy in the back

[Fishethland]

Greetings, people of the Shetland forum! This is my first post here, hope somebody's around to answer it

I recently bought a 1979 498 Hobby with a 50hp Honda engine. Mostly the boat suits my needs very well (fishing), but there are two major problems:

1. When at sea with two people in the back of the boat it takes inn water through the hole that's cut for the engine to be able to pivot/turn. This happens only when there's a bit of waves, but not overly much. It's easy enough to drain it using a pump, but very annoying having to sit an think about it all the time while at sea.

2. When riding the boat with two people in the back, it almost does not plane. Yesterday I had to wait for my own waves to catch up with me and use their push to get it up. This makes me think the boat is heavier than it should be. Which leads to....

3. Theory: Is my boat really this heavy in the back from factory, or do I have a problem with e.g. water in the double hull? Is this a known problem with these boats? Are there any ways to find out?

Thankful for any reply that might show up!

[Barnyno5]

It may sound a bit daft but I found concrete paving slabs in the bottom of the Fuel and battery compartments which were possibly used to stabilize the boat, I feel sure you will have seen them already but I didn't until stripping everything out. Regards and Happy boating

[Fishethland]

I'm pretty sure there aren't any slabs in my boat

Did some more digging. Found holes in the very bottom of the boat. Anybody know what these are supposed to do (see pictures)? It seems there is some water contained in there, because as I dried it up, more kept coming. Not much, though. As can be seen in the pictures, there is no hole from the "below deck area" (excuse my English boat vocabulary..) to the back of the boat where I have my bilge pump placed. I reckon I'll drill a couple of holes so that water can flow freely.

It seems my boat has been altered. It has a 70 litre petrol tank. To make place for it I guess the previous owner made incisions into the deck.

Images can be found in my photostream at Flickr:

https://www.flickr.com/photos/photosven ... otostream/

[daveinglasgow]

Hi

the honda 50 is the perfect engine for that boat and I had my 535 out with the same engine doing 35 mph with 3 adults so that will show you that you have a huge weight problem i.e. 200kg of problem or the engine is ex commercial and lost compression so

1: do a compression test
2: check the revs are around 5500 give or take 100 or so

if that check out ok its the boat and as I said above its not just a few kg's so 200l of sea water? , other ballast or engine not sitting right

Dave

[Fishethland]

Thanks for the reply Dave.

Regarding the 535 - tried to find the weight of it, but didn't find much. I think my 498 is 510kg "dry". Is that about the same as the 535?

The engine is not ex commercial, it is as good as new as used very little (could be too little..) But it has been stored well.

Compression test I have no idea how to do. I do however not think the engine is the problem. The previous owner said he only got 25 knots at max too, and that's from the engine was new. The revs are at about 5500 at max. I tend to cruise at right below 5000.


So I'm left with a boat problem, but where could the water be?? Did you see the pictures I posted? I cant imagine there being any room for water below what I photographed - or?

[Fishethland]

To answer my own question, I now found that the 535 weighs in at 363kg, whereas the 498 is 510kg, so there's the weight difference Seems the 498 is a very heavy boat construction-wise.

[daveinglasgow]

ok based on those numbers and other boats I know put fins on the engine.

dave

[alandvs]

I agree with Dave about the fins. I have a 498 with 50 hp merc with fins and it planes pretty well when the bottom of the boat is clean of weed and limpets. Sometimes when there are a few on board it is hard to get on the plane and it helps when I send the biggest of us up front of the boat, that helps. It would help more if we chucked him overboard, haha.

Alan