1978 305 OMC in 21' Bell Boy Cuddy

[GordonHemi]

Hi folks, first post on here and in fact ever Trying to determine what the exact model # of my sterndrive engine is. Just got the boat given to me and anxious to get it fired up but need a coil and a few little parts. Cannot find anywhere on line where to find the engine ID tag tho. Valve covers and entire engine are just all blue. Casting number on block 460777 tells me its a 78-79 305. Hull number AMM21309M78G tells me the boat is a 1978 (Bell Boy Cuddy). The Drive ID tag says: model #981112 (found nothing on that) and serial #W165237 although I believe the bottom end has been replaced with a slightly newer one?? Stringer I guess..

Air cleaner has B175-37 & 162.041 72 stamped on it although that may just be for the air cleaner. Somebody said look down by the flywheel but i tried and it's pretty grimy down there. The boat has fresh water cooling on it which is nice. Not sure if that's after market or original though it seems old. Wondered if the missing info is hiding under there? Also found a number cast into Starboard riser which I think says 909215S which means nothing although its very close to some of the 1973&4 model numbers. No I don't have dyslexia ... All the model #'s seem to start w 99. Any help in the next few days would be much appreciated. Dying to find out the hp rating. The boat is called Sea Dog though so not expecting it to be as fast as my last boat Robalo 227. Best boat ever.

 

[southkogs]

Welcome aboard:

Typically the engine and drive are ID'd by a tag on the engine itself. You're right about the model numbers, but that you're looking for is typically on the rear mounts somewhere. Mine was on the starboard (driver's) side.

Assuming all of the years are correct, you've got an OMC 800 hydro-mechanical shift Stringer sterndrive. Posting up some photos we can probably confirm it a little more certainly ('77 was the last year of the electric shift, so it's possible you may have a 'last year's' drive on there.

HP is somewhere around 220 - 240 if all the years are right.

 

[Bondo]

HP is somewhere around 220 - 240 if all the years are right.

Ayuh,..... Welcome Aboard, Gordon,.... southkogs knows way more 'bout Stringer drives than I,..... But,.....

A 305 of that vintage, I'd guess the horsepower at from 'bout 195 hp, with a 2bbl. carb to 'bout 225 hp with a 4bbl. carb,...

 

[southkogs]

... southkogs knows way more 'bout Stringer drives than I ...

... Not in this case.

Made my first post at the airport waiting for a plane: and if we were a few years earlier, I woulda' been closer to correct. I think that Bondo is closer to right (now that I'm sittin' still and looking at some more stuff). Quick search of some older topics shows a 305 in rigs like the 185HP. Some of the older electric shift models had the 305 under bigger HP ratings.

Good catch.

 

[GordonHemi]

Hey Fellas! Thanks for the welcome & the info! I went out just now and found no tag or numbers above the starter however under much grime & blue paint I have the following stamped into the little square on the block just above the timing chain cover; T3030CRX under that 28B121981. I thought I'd be smart and figure it out for myself but thus far google isn't helping. I'm wondering if it's some sort of remanufactured engine? Although the block # still says it's a (460777) 78-79 305.
btw its a 2 barrel. Another site said that that block number was either 220 or 240 hp... pics to follow when I figure out how to get them posted

 

[Scott Danforth]

220 or 230hp with a 4 barrel. However that's flywheel hp, not prop hp. About 180 at the prop.

The 350 had more power, however the stringer never had more than 260hp in front of it. It can't handle too much power.

What does it matter on hp rating? I would be more worried about the health of the OMC stringer, specifically the vertical driveshaft splines and the ball gears

 

[GordonHemi]

OK thanks. I managed to decipher what the engine stamp T3030CRX means: Built in Tonawanga, March, maybe 30th (exact date not too critical) and CRX suffix is for a 78 LG3 305, dual jet 2 barrell carb w 140 horse & 8.5:1 compression. It has an application code of "G" which isn't for a vehicle but it's not specific on what it was for. I'm hoping this 140 hp rating was closer to the 175 or 185 when it was outfitted with free flowing marine exhaust etc.

You make a good point about the leg though, my hot rodding past wants 400 hp but in reality I'll need to drive this thing like a granny out to fishing grounds to keep the bottom end alive. West Coast of Victoria, Vancouver Island BC, Canada (I didn't look to see where you guys are from yet...)
Going to work on the second number next 28B121981

 

[Scott Danforth]

nearly all the GM motors for marine use are built in the Tonawanda engine plant (GM's industrial engine plant). the exception are the 502's (most of them come from the GM performance parts division) and the 3.0's which come out of mexico

marine exhaust is far from free flowing

if you want 400hp, you are going to have to pull the 305 and stringer drive assembly and rebuild the transom for a different outdrive and motor

 

[southkogs]

It's not unusual to have a Franken-Stringer. As people were trying to keep 'em alive, they mixed pieces and parts sometimes. That may explain some of the lack of details.

 

[GordonHemi]

Hey! It actually ran! We tuned up the points and dropped in a MSD Blaster2 45k volt coil but continued to get weird voltage readings. After we disconnected all the extra mystery wires running to the coil/ballast resistor and distributor/old shift module?? and ran a simple hot line to the coil and a ground line to the distributor she fired up and ran smoothly

We had syphoned off the old gas and put in new stuff. Only issue so far is a leak from a crack in the port side exhaust riser. Not sure how JB Weldable that is? The water in our big plywood box got hot so it seems the pumps are working.

The next thing I'm wanting to learn about is how to see if the foam filled "K - 33" using "web-cor" state of the art (in 1978) technology hull is water -logged?! Will drag it over the scales. I think we either have a 2220 "overnighter" model or maybe a 2105? the actual hull is about 21' ish & its a cuddy

This is cleaned up
These numbers don't start with 99?!?! Bottom end of drive definitely been replaced? Boat came with another one...

Hopefully the name "Sea Dog" isn't indicative of it's performance Although I was kidding earlier about wanting 400 hp. 185 will be fine if it floats.
So let me know if I'm to start new threads about what this boat is exactly as well as the hull questions. Any info would be greatly appreciated!

Many Thanks, Gordo

 

[Scott Danforth]

the extra wires coming from the shift module are going to be needed or you wont get the motor out of gear when on the water. that is the shift interupt switch.

 

[southkogs]

Weird - I can't the 98 number any the stuff I have ... BUT, when I did some searching it looks like that's a legit number from some '78 hydro-mechanical shift units.