new motor question

Hey Doc

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Explorer
I just inherited a 24 explorer and added a new 250 Yamaha. The boat stays in the water most of the year, with the new motor one of the scuppers is now under water. Any suggestions on how to keep the marine growth out of the scupper and the hose that drains the cockpit? Secondly, the tip of the lower unit is in the water and will need to be painted unless it can be raised to a higher position on the stem. The motor is mounted in the lowest hole and can be raised by 3 holes or about 3 inches, enough to clear the water when tilted. Any experience out there with the height on the gil bracket or is this going to be a trial and error?
 
You can paint the inside of the scupper - I do that. Slop it in there with whatever you have lying around that can reach in. Or, try balancing the boatload a little better - it might even things out just enough that it gets that scupper out of the water without putting the other one in it.

Yes, trial and error with the engine height (but it's no big deal to paint the front of the gearcase. You may need to paint some of the engine bracket, anyways. The goal, in terms of height, is to get the engine towards the upper range of it's RPM range at WOT (this is also a variable due to the prop). But another thing to look at is the anti-ventilation plate while up on plane at a good cruising speed. The AV plate should be skimming across the surface. This equates to ROUGHLY having the AV plate 1" higher than the keel for every 1' it is mounted back from the transom - you can at least start with that... although hopefully whomever installed the engine already did that.
 
I've seen the inside of the scupper painted and the entire thing painted (not that I would recommend it).
For the lower unit you can tape off and paint or just use a brush each time and hit it. I do the latter and it's worked out fine for me 13 and counting seasons
 
Another easy option to consider: stand on the bow. Does the scupper and engine come out of the water? If so, add ballast in the cabin under the front cushion. The boat might ride better as an added benefit.
 
Another easy option to consider: stand on the bow. Does the scupper and engine come out of the water? If so, add ballast in the cabin under the front cushion. The boat might ride better as an added benefit.

Good idea. I know GW used canvas bags and lead pellets in some early 330s to change the position of the bow. I recall a person complaining that the canvas let loose and there were pellets all over the place.
 
Thanks for the replies, I will give each a try. Another question, does any body have trouble with rain water. Each time it rains the boat takes on water and I cannot find where it is getting into the blge.
 
You must have installed a heavier 4-stroke motor where a lighter 2-stoke used to live. I would be very wary of moving the motor vertically on the mounting holes, as this will most likely result in cavitation if the cavitation plate of the motor is not even with the running surface of the boat. With regards to water in the bilge, check all of the cockpit drain hoses and fittings to ensure none of the hoses are cracked. You could use the process of elimination and block off one drain opening at a time, then see if anything changes after each rain event. Also make sure the garboard (drain) plug is installed, and keep in mind that some water could enter the bilge via the anchor locker on the foredeck.
 
If you have any pie plates on the deck, check the orings. They shrink and a surprising amount of water can get by.
For ballast, I bought ultra thick waste bags and 160 lbs of pea gravel. Double bagged the gravel. Not nearly as dense as lead, but I had plenty of room for it. Non toxic to boot!
 
When I replaced my 2 stroke 225 on my 24 offshore with a Yamaha f250, I had the same scupper problem. I moved my batteries out of the starboard rear compartment and relocated them up front.
 
Many thanks. Now I have a lot to try.