omc motor swap
- Thread starter circuit19
- Start date
Chris E
Member
anything is possible, the question is why would you do such a thing? usually you power up a boat not go backwards. the 2.3 ford is a horrid marine engine.
what is a 175 omc outdrive - they never made one, it's either a 400 or 800 series or a cobra. cobras were made after 85, so it's probably a 4 or 800 series.
what is a 175 omc outdrive - they never made one, it's either a 400 or 800 series or a cobra. cobras were made after 85, so it's probably a 4 or 800 series.
okay guys this is my think'n. I'm looking for way more economy since this 302 is a fuel guzzler. I also think that there is dependable 4 bangers out there that get close to the 175 horses that the 302 has. My sterndrive has a big label on it that says 175 on it so that's how I came up with calling it a 175 omc sterndrive. the model # is 981059 so if that's a 400 or 800 i guess I'll have to find out. This is my first boat in 30 years and I have to rebuild or replace the motor before I can take it out next summer. I already know that I can buy another boat for less than I'll have into this one once I'm done but this thing only has 250 hours on it and everything else works fine and is really clean. The guy who had it forgot to winterize it last year and the block is cracked so since i have to replace the motor i want to make it more economical so it will be able to be used more since I'm on a fixed income. So I'm looking to see what kind of possibilies there are before I start. I hope i can find out that info on this forum and put it to good use for many years. thank you for your replies and I hope you may have more info/suggestions etc. for me
Fun Times
Active Member
Hi, You might want to keep this in mind that you more then likely will be putting up a lot of money up front in different part's to make you'r 2.3 work over the V8 engine.
You may need a new flywheel housing for the 2.3 engine so you can set it in the boat, You may also need to rig up A front motor mount base to the boat it's self. You will need to change the gears inside the drive to work with A 2.3 over the gearing you have now for the V8 engine, ect.
IMO, With just some of this in mind you will more then likely spend more money up front in making all this work, Then you would spend using the boat all summer long in fuel even with a V8, Because more then likely the chances are you will only use the boat a few times a year here and there And you may not burn as much fuel as you might think vers how much money you may need to put up front.
Have you looked a round for a good V8 engine just to see what the price might be veres trying to install the 2.3l engine, I believe over all it might be cheaper to stay with what you already have, Then going the other way.
Either way you go I wish you good luck, And sorry to here about your cracked engine.
Also I thought you might like to read this link, It kind of touches base with what I was trying to say here. http://forums.endlessboating.com/forums/showthread.php?t=638&highlight=gear
You may need a new flywheel housing for the 2.3 engine so you can set it in the boat, You may also need to rig up A front motor mount base to the boat it's self. You will need to change the gears inside the drive to work with A 2.3 over the gearing you have now for the V8 engine, ect.
IMO, With just some of this in mind you will more then likely spend more money up front in making all this work, Then you would spend using the boat all summer long in fuel even with a V8, Because more then likely the chances are you will only use the boat a few times a year here and there And you may not burn as much fuel as you might think vers how much money you may need to put up front.
Have you looked a round for a good V8 engine just to see what the price might be veres trying to install the 2.3l engine, I believe over all it might be cheaper to stay with what you already have, Then going the other way.
Either way you go I wish you good luck, And sorry to here about your cracked engine.
Also I thought you might like to read this link, It kind of touches base with what I was trying to say here.
http://forums.endlessboating.com/forums/showthread.php?t=638&highlight=gearYes I have looked a little but all I have found is really expensive stuff or am just finding out that rebuilding this motor isn't going to be like doing a car or truck. I did find a 351 for 1500 but that's just another used motor and I would rather go and rebuild it so I'll know how dependable it will be. I've done many motors and am comfortable with that end of it. From the looks of it I may have to find a 302 block(omc) and go from there. But I do keep hearing that the omc isn't the way to go. Is that from lack of parts or is it a durability issue? I'm also curious to know if I can use an automobile block and just put the internals from what I have in it or if there's too many differences to overcome using a car block
Chris E
Member
boat engines are completley different from car engines, different cams, carb, starters, alternator, distributors. most marine engines come from the automotive origins, although a few are stirctly industrial usage.
by attempting to convert to a 2.3 you will cause more frustration then you will ever see in benefits. my suggestion to you would be to rebuild what you have install a 4 barrel carb and run it lightly. by keeping the secondaries closed, you will enjoy better fuel milage than a 2 barrel will offer (just look at the barrel size and you'll see what i mean). run hard, the 4 barrel will use more fuel - keep it under 2800 rpm and you should find it reasonable.
OMC doesn't make sterndrives anymore, and although they weren't a bad product, they weren't overly good either. parts are becoming more and more scarce. so eventually the whole issue will be scrap.
in order to convert to a merc set up, you would need to fill a huge hole in the transom and do major fiberglass work, i don't think it's worth it considering the age of the boat.
marine parts are considerably more expensive than automotive because of the enviroment we expose them to as well as the lower volume of parts produced. however, you need to use marine parts for the durability.
by attempting to convert to a 2.3 you will cause more frustration then you will ever see in benefits. my suggestion to you would be to rebuild what you have install a 4 barrel carb and run it lightly. by keeping the secondaries closed, you will enjoy better fuel milage than a 2 barrel will offer (just look at the barrel size and you'll see what i mean). run hard, the 4 barrel will use more fuel - keep it under 2800 rpm and you should find it reasonable.
OMC doesn't make sterndrives anymore, and although they weren't a bad product, they weren't overly good either. parts are becoming more and more scarce. so eventually the whole issue will be scrap.
in order to convert to a merc set up, you would need to fill a huge hole in the transom and do major fiberglass work, i don't think it's worth it considering the age of the boat.
marine parts are considerably more expensive than automotive because of the enviroment we expose them to as well as the lower volume of parts produced. however, you need to use marine parts for the durability.
Okay. Thank you all for the info. I appreciate all of your input and it looks as though I will have to try and find a 302 omc block and rebuild it since my block is cracked. So at least I'm 1 step closer to getting this project underway. If you all have any idea who I might possibly contact to get a block or where I might look next it would help. thank you!
Fun Times
Active Member
I would think about using the phone book and looking up all your local engine rebuild shops and talk to them and see if they have a good engine block in the back room some place they might let go for cheap, [Good in as they went thru the block already Good]
Then put your good marine parts in the new to you block, Then Buy the other stuff you might need to make the engine as new as you can for cheap, Rings,Gaskets,ect. If your carefull some times parts can be cheap But labor will kill you, But if you can do most of it your self then you should be good to go.
Do you have a engine stand, And a way to pull the engine out of the boat??? http://www.harborfreight.com/cpi/ctaf/Category.taf?CategoryID=516
dave
Active Member
you can get a 302 from a mustang or a truck and it will be fine, just make sure you replace the frost plugs with brass ones and make sure you install a marine camshaft. as for the pistons, bearnings, ect quality automotive parts will work fine, just make sure you use a marine gasket kit.
