1978 240SRV Seadanbridge

[mdwaller]

I recently purchased a garage kept, freshwater only, 1978 Sea Ray SRV Sedanbridge. It been sitting in a garage since 2001. It has twin Mercruiser 470’s with the alternator conversion kits and freshwater cooling system on both. It has Alpha 1 drives. The port engine was rebuilt in 2000 and only has 5 hours on it. The starboard engine has roughly 300. We’re doing a total restore on the boat to bring it to modern standards. The fuel tank I believe is 70 gal and we are going to replace it. I would like to have 100 gal or better, but have been told that the boat won’t get on plane with a 100 gal tank. That doesn’t make much sense to me, since this same model was also sold with a single 470 engine, and a 70 gal tank. Would by extra horsepower not be enough to go back with a larger fuel tank? My grandfather had the exact model with twins. He somehow added an extra 40 gal auxiliary tank. Don’t remember any issues, but then again I was young. Does anyone have any experience with this? Thanks in advance.

 

[Lazy Daze]

Wow, can't complain about the condition of that!

That doesn't sound logical. 30 gallons is roughly 200lbs. It's not like the weight is being put on the platform. Besides, there are many ways around it if it does cause a slight planing issue - and that's the most that would happen... a slight difference. You can add more weight up front... more chain, store more things up front, even just dead weight... install larger trim tabs - just to name a few. Wanna find out for sure, before you do it... add 200lbs in the approximate location (cockpit floor is plenty fine for this). You can use water in containers/coolers, sand bags, weight lifting plates, even a good buddy!

 

[Thornton69]

Nice find. I Have a similar hull with a 100 gal tank. It does have a single 5.7 though and was ordered custom with hardtop and no command bridge. I would agree that more fuel is more than likely not going to effect much if placed correctly. With the twin set up, what size are your trim tabs? I take can take off with over an additional 1000 lbs but definitely need their help to do so. Also, if your drives are original then they will be pre alpha which do not like hard take offs. Even though only 470's, believe their upper gear ratios still put plenty of torque to the lowers.
Interested in seeing more pics of the interior layout if you don't mind sharing them. Ours was set up more for killing fish than cruising. Looking for ideas on how to make things more comfortable for the cruising part.

 

[mdwaller]

Hi, thanks for the reply. This is the same model my grandfather had when I was as kid and we used it for killing fish on the Texas Gulf. That's what I intend to use it for as well, but want some comfort for the family as well. We're adding A/C and updating everything. As soon as I can send some pics I will. Sounds like you have the sedan cruiser like this one

?

 

[Thornton69]

Very similar yes. There is no seating in our cabin though allowing much for visibility while cruising other than from the helm. Just a bench running fore/aft on port side. Would like to move things around to better utilize space and change that. Look forward to your pics when you have time.

 

[mdwaller]

Wow! That thing is sharp! I thought mine looked good for a 78’!

 

[LiquidWrench]

I've got a 260 dancer with twin 470s and 100 gal tank. Only time I have problems getting on plane is with a full tank of fuel and 6 or 7 people on board. 470s have a lot of torque and are fairly reliable when you get the bugs worked out of them. This hull with twins does make the boat a little a$$ heavy though so if you've got a few people on board it helps to have them go forward till you get up. Just an FYI, the 470 uses the same drive ratio as the 4.6L v6 so if you do have the original #1 drives they are a bolt on swap with the alpha gen 1 as long as you have the correct input shaft. Counter rotation on the port engine helps low speed and docking a lot too. That is next on my list to do.

 

[Lee Hanson]

WOW! I like it... especially the fly bridge. My next one will have it. Lots of referb going on here too. Best to you.

 

[mdwaller]

Very similar yes. There is no seating in our cabin though allowing much for visibility while cruising other than from the helm. Just a bench running fore/aft on port side. Would like to move things around to better utilize space and change that. Look forward to your pics when you have time.
View attachment 52210

Hi, would you mind sending me more pics of your boat? We're looking into doing away with the sedanbridge and doing something similar to yours. My email is matt@gamefaceimaging.com
Thanks in advance

 

[Thornton69]

Hi, would you mind sending me more pics of your boat? We're looking into doing away with the sedanbridge and doing something similar to yours. My email is matt@gamefaceimaging.com
Thanks in advance

Sent 4 pics of it in it's original form. I have done some custom additions I included in the next 3 in case you were interested. Have a list of more ahead of me. Going to add a windlass, redo interior and add an Alaskan style bulkhead door in the future.
Have you contacted Sea Ray? they are pretty helpful and am sure would have some ideas and possibly plans from similar models. Mine was a custom build and they had no records for it. Could only tell me where it was built.
Hope this helps you.