Repower '74 240SRV

[seacure]

I am considering repowering 1974 Sea Ray with an upgrade to a factory rebuilt 350 cu in. Chevy tied to existing stringer outdrive, which is in excellent condition. Can anyone share their experiences with this approach, which will run around $2300 compared to $15,000 for new engine and transom modification to Mercruiser. Thanks. John

 

[ghuskin]

I'm not an expert, nor have I had to repower my boat - yet - I will give my .02.

If you absolutely have to have NEW, go the $15k route.

If you have extra $$ burning a hole in your pocket, go the $15k route.

If you are confident that you will be getting a reliable rebuilt engine that will bolt right in, go the $2300 route.

just my .02.

Gregg

 

[Dirtguy]

The idea that if you spend more money, you get more product is just plain silly. Someone makes more profit on the same product.

I was looking at a 7.4L replacement and had discussed with many possible suppliers until I came to the conclusion that it was a waste of money to buy an unknown rebuild. So, having the skills and desire, I rebuilt it myself and have not looked back.

The money saved also afforded me to upgrade reliability items for a higher quality package. It's now fresh water cooled, higher capacity oil pan, high volume oil pump, higher output alternator, electronic ignition. While it was out, I also installed a higher volume bilge pump and a through hull for a bait/washdown pump, and went to a larger through hull intake for the raw water intake. It also has a higher capacity screen filter.

I'd recommend going for a quality rebuild, or a new truck crate engine from GM. Try JEG's or Google "GM crate engines." Be sure to install a marine cam. And also looking for a newer drive system. If that is the older OMC "stringer drive" that I'm thinking of, parts are getting more and more scarce. The move to a newer Merc is a sound investment.

just my .01.
dg

 

[KRB64]

Dirtguy, what did your total repower cost?

 

[Dirtguy]

Total for all the parts and additions was $3100 and change. Engine assembly was $1600 in hard parts and machine work I couldn't do. Got alot of new hard parts off Ebay. New crank, new rods, new pistons etc from one of the suppliers. They do have great kits with everything matched, cheap. The rest was from Jeg's. It's nothing really special, just a solid BBC made for a boat. Low end torque and needs to be reliable, and economical, (like that's possible Cam is a Merc HO version, intake manifold is iron. Closed cooled. Crank mounted raw water pump to eliminate one belt.

I did get some good deals on used Merc parts from many sources. Hurricane Katrina, sadly enough, put alot of good late model boats in salvage yards. Many good drive parts to be had.

You can do boat stuff inexpensively if you have the time to do some looking and research.

dg

 

[KRB64]

Not bad at all. Plus you have the satisfaction of doing it yourself!

I remember in the 80's when I first started messing with engines we'd figure about $100 per hole!

 

[garryowen]

one thing you should into consideration, is what that new extra hp is going to have on that old stringer drive.
it might be in good shape now, but that might be the straw that breaks the camals back
unless there is a something wrong with your motor now you might be better to leave it alone or over haul it, if just needs freshened up

 

[Dirtguy]

Good point about over extending the durability. The difference is only a couple of hp or cu. in. to the plus side. And if not over propped, it should be ok.

Speaking of, Did the 454 ever come standard on an Alpha!!??

Bravos and TR's I do remember.

DG

 

[garryowen]

yes. it was a sea ray package and was painted oyster white with sea ray decals
they only did it for 2 maybe 3 years and couldnt hold them together. they came with 132 to 1 gears and made a 150 to 1 heavy duty gears and these are the only gear sets you can get much life out of. it was just about this time mercuriser came with the bravo I and limited the alpha to 300 hp.
we run at higher elevations so we dont get full hp any way

 

[jitts3]

I am considering repowering 1974 Sea Ray with an upgrade to a factory rebuilt 350 cu in. Chevy tied to existing stringer outdrive, which is in excellent condition. Can anyone share their experiences with this approach, which will run around $2300 compared to $15,000 for new engine and transom modification to Mercruiser. Thanks. John

Just dragging a old post back up front. What ever happened here? Love to know.