stillcrazy26

I got rid of the Donzi and bought a 2004 Chaparral Sunesta with a 5.0MPI Alpha ll. !00 hours stored dry. BUT it leaks water ! I have been on the Chaparral forum and find that this is a common problem. The answers have been questionable workmanship with hose clamps missing, hoses near the water line left unconnected, Enlarged thru bolt holes without sealant or backup washers, unsealed/loose thruhulls, unsealed swim platform mounting hardware. I am not talking about rainwater. I am talking about just sitting in the water with the engine off. It takes on 6 gallons in a little over an hour.
Now I have checked all the above and they are OK. I have checked the drive bellows and shift bellows. I have checked the water inlet tube and hose and all clamps up to the W.Pump. The hull drain is sealed. I inspected the Hull on a lift and nothing that I could detect.That brings me to the Drive mounting parts, inner and outer. I have laid next to the motor and watched but cannot detect a slow leak. I have used a inspection camera for the places I couldn't see and The engine is not leaking. The remaining spots are the exhaust "Y" and the trim lines connector plate seal. How about out of specs transom flatness ?
Has anyone had a mystery leak on a A ll drive ?

V.I. Outlaw

I had a mystery leak meself. It took some poking around but I finally determined that the upper hinge pin or swivel pin whatever you want ta call it was a little worn and that caused the seal around it to leak. With your boat on the trailer,lower the drive then physically try to lift it up and down to check for play in your hinge pins. Good luck. Hopefully they are not worn or you have to pull the engine to fix. Mercury makes a repair kit that you can use without pulling the motor but requires drilling fairly large holes in the side of your gimbal housing. I choose to pull the engine.

US1 Fountain

iTrader: (1)

That much water shouldn't be too hard to determine if it's leaking high or low. Also check the manifold seal bolted to bottom side of transom assembly where the trim hose connect.

stillcrazy26

Thanks guys
Yes, I have three "hot" spots to check. The Trim hose connector plate seal under the Gimbal housing can be replaced relatively easy The other two are Exhaust "y" seal and the two lower transom plate bolts but they require removing the motor.
Other Chap owners have found that the thru bolt holes were drilled oversize during installation and then improperly sealed. Seems like someone at the Factory didn't like to get their hands dirty because most of the items installed on the outside of the boat were not sealed !
Anyone else have a hard to find leak ? I laid along side the motor feeling for a weep under the inner transom plate and could not detect any leak but still the water came up ?? You are right. I should be able to see it !

US1 Fountain

iTrader: (1)

The Gen II's transom assembly's bolts are all within the sealing gasket area. Even if the lower holes were drilled oversize, (unless they used a holesaw )they are still inside that sealing are and shouldn't leak. Beside, why/how would they have beeen drilled oversize? The drill jig has drill bushings for the drill bits. A larger bit won't go in, and I'd be hard pressed to think Chap drilled these free handed. Have seen the exhaust y-pipe o-ring be a leaker before because the mounting bolts were loose.

FBRONCO

iTrader: (1)

I had to pull my engine on two different boats and put the boat in the water with no motor and a few guys on the swim platform to find leaks. Also look at anything bolted on the transom like trim tabs, brackets for swim platforms. If they are not sealed good, they will leak into the transom and then show up in the bottom of the bilge.

dereknkathy

find a boat ramp with running water. back boat partway down ramp. NOT in the water. turn on hose. fill bilge. you will see the water come OUT where it goes IN...

Knot 4 Me

I've got a 2004 Chaparral 260 SSi. I've never had water in the bilge unless I get caught out in the rain. It is always bone dry. Chaps of this era, though fundamentally solid boats, had a bunch of drunk/hungover Georgians building them for sure. Are you sure all the thru hull fittings and hoses at the waterline for the self-bailing cockpit are all dry? If your boat is like mine, the two main cockpit drains are right at the water line. Are the rubber flappers in place on these thru-hull fittings?

PRIMECUT

That much water has to be a good sized leak,shouldn't be too hard to find .

stillcrazy26

Again my thanks for getting in the "Ring" with me. I have installed over 250-300 drive units in my time, both with and without the jig. Every thing from Alpha One to #5's along with Kama and Arnesons, so that's what bites me. Yes the bolts are inside the seal area and that's why they can leak. Ever notice the little rubber seal on the lower two bolts ? "Oversize " drilled hole was a quote from a chaparral forum member and what he found. yes the rubber seal should have sealed regardless of hole size.
Filling the boat with enough water to look on the outside is not a good idea unless it's an outboard and your trailer is strong enough.