My question is, has anyone used a Marine engine in their rod b4? and what ways are there for checking for Reverse rotation engine?? Recently received a 26ft boat and trailer in trade. Boat is trashed. Just wanted the tandem axle trailer to use here around the property. I traded a used Air scoop for it, so maybe about $150 in it. But i happened to notice it had a 250Merc in it, I could tell it was a SBC, so I ran the Casting # 3970014 which comes out to a 68-79 350 2 or 4 bolt, I yanked it out today and threw it on a stand, letting oil drain over night, I know it turns over by hand. Plan on pulling pan tomorrow, mainly to see if it is a 2 or 4 bolt and to take a quick peek at bearings. I figure it probably is designed to run at higher rpms, but might lack tq?? idk, but might be the perfect donor for my lil 40 pickup build. Plus I stole the steering wheel, air horn, chrome trim, wiper motor and other odds and ends I thought I might use. Stripping all the aluminum for scrap and Burning the rest .. Anyway, Thanx in Advance for any info, JT from IllinoiZ
Starter on engine side of the flywheel normal rotation, starter on trans. side counter rotation. General rule of thumb.
Anything marine is expensive. I should think if it is any good it would be worth more as a marine engine if you can find a buyer.
I just assumed higher RPM because the faded tach looks to have a redline of 6300RPM.. But IDK, Marine might as well be written in greek to me.. lol
Marine engines are tire burners.I really like them. I have been blessed to find the ones out of large boats that are built for low end power. I used my first one back in 1982. Put a crusader (427 chevy) in my 67 camaro.It was a counter rotater out of a sportfisherman.Just switched it back and put her in.Torque was great. Just got a Mercruiser(454)for my next project. It came out of a 30 foot yacht.Has 330 hp at a low 4200 rpm. This one will be a torque monster as well.It is standard rotation. Starter can be on back of either rotation engine.They are put up there to get them out of bildge water.I have a pair rear mount starters here at shop.They turn opposite. Wheather it is built for high or low rpm depends on type of boat it was built for.I always go for the engines out of large boats because of low end grunt.But smaller boats that are fast will have engines built to cruise at high rpms. Anyway,the basic block is chevy.You can take a car engine and put it right in a boat. We used to do that back when we built our boats.
I retired from the marine business and just returned to it, so I know a little about them. I used a boat 350 Vortec in my 23 and after freshening it up with a rebuild it was a great motor. Essentially, the block and internals of your motor are pretty much Chevy, and some parts might even be truck parts for a little more strength. The cam profile is very much like a truck grind and tops out at about 4600 rpms........that is redline on most boats. Some high performance engines go higher, but that is where yours will redline. It will have a lot of torque as opposed to lots of revs, but a cam swap can cure that. I suggest changing the cam or it will sound like a boat (I'm serious). You can use standard Chevy parts for the complete rebuild, including bearings, rings, gaskets, etc. Any aluminum or cast iron intake that fits on a Chevy car will fit your motor. Being that you live in Illinois, the engine probably was not exposed to salt water, so the block and heads should be no more corroded than one used in a car. If it was a salt water motor I would probably tell you to look for another one. Don
i got a deal on bbc mercruiser counter rotater 454 4 bolt forged crank big 7/16 rods changed cam time chain was gear drive new starter stuffed a hei holley carb ran great for years be carefull on boat motors run in salt water
Sometimes there are serations on the crank in the rear main seal area. If the crank is used in the opposite rotation of its intended use it will pump oil out of the engine (slinger).
I have two 351W motors that came out of a twin screw boat. One is a counter rotater and the other is normal rotation. One of the motors has about 100 hrs on it after being replaced, then the other died. They ended up replacing both at the same time and I got the cores (so to speak). Are the salt water motors undesirable (these were fresh water cooled) due to internal corrosion or is there something else I need to look for? Hate to scrap them, but I will if there no good...
^^^^^^^ If those motors were fresh water cooled you are ok. The freshwater cooling system (for those who don't know) is a lot like the radiator system on your car, except that the "radiator" ( called a heat exchanger in a boat) isn't cooled by air, but by seawater. The seawater is pumped in and circulates inside the heat exchanger and is then pumped back overboard, never touching the sealed coolant that circulates inside the motor. The engine cooling system is sealed so that salt never gets inside. But the engines themselves are not any different from one that is raw water cooled (where the water the boat is operated in becomes what circulates within the engine block) Most marine engines, whether fresh or salt water cooled, simply have some items that need stripped off to make them suitable for car use. (Like seawater pumps, exhaust manifolds, circulating pumps, thermostat housings, etc.) BTW, hang onto those 351 W engines, they are starting to dry up. A guy I work with has a SkiNautique with a tired 351 and we have been starting to look for a fresh crate motor for him. All that we can find are remans, no new engines. Don
I am in the marine business. If you took this engine out of a single application it will be L.H. rotation. industry standard. A R.H rotation is counter rotating. The starters are in the same location on Mercury. Strip all of the plumbing and exhuast off of it and all you have is a small block chey with a 4 bolt main. If it is rh rotation change the cam and the starter to L.H and there you go all done.
So what you are saying is that if you stuffed one in a '59 Buick you would have a big ol boat that sounded like a big ol boat. If you don't have someone likie Don around to tell you what you have another way to tell is to look at te timming marks on the balancer, you may have to think about it a little bit. The BTC will be opposite on a reverse motor.
Do you mean running one on the street or MPG on the water ? On the street much like any engine . On the water a different story, I have two 454's on a 44 ft. boat and I burn 33 Gal. per hour at 3100 RPM @ about 24/26 MPH
I don't know about SB Chevy boats, but a FE BB Ford has a starter always in the same location. Its just turning in the opposite direction to cars in its RH rotation versions. Steve
Even low hour Raw Water (lake water or ocean water) cooled engines will rust up the water jackets in short order. Beware! They will pin hole into the cylinders and you can't tell until its too late. Applications with heat exchanges have closed cooling systems running antifreeze and should be similar to car applications for rust. Steve
Hey everyone, I appreciate all the info and responses, I just turned on heat in shop and I plan to rip that pan off.. suspense is killing me..lol.
So, on the 351W motors how would one tell the difference between rh rotation and the lh rotation? These are longblocks, no goodies bolted to them...
I ran a marine 350 in my car with a 268H cam and 64cc 327 heads. Then I pulled that motor out of my '57 Chevy and put it in a '60 Stude that had a 350 industrial Pontiac in it before that. Confusing huh? It made great torque in both cars.
you can turn motor over manually in correct rotaion and look at rotor to see if its right or left rotation motor
That is a distinct possibility. I haven't seen the motor yet, only what the guy is telling me. I will have to check that out for sure. Thanks for the heads up. Every other single engine boat I have ever seen is left hand rotation, maybe Ski Nautique did that to counteract torque or for some other performance reason. Don
I owned a Nautique for 6 years and drove several others and never learned why they chose to use right hand rotation. With the driver on the right side (starboard) it makes the boat harder to dock than a left hand engine. When operating with the driver only in the boat the torque does help level the boat. But it is a tournament boat and when driving a tournament with a timer and judge sitting on the left side of the boat the torque works against leveling the boat. Maybe it's an economic decision. Maybe they're able to make deals on big lots of right hand engines left over from the previous year.
Get the timing cover off. Chain or Gears?If it has gears you can't just spin it other direction because pistons are flipped for right hand rotation(offset wristpin) also will have different seals made for RH rotation