I just bought a marine spec. 4.3 to put in my 96 Blazer. From what I understand, the mechanics are all the same except the water jacket, freeze plugs, and all coolant contacted parts are brass or corrosion resistant. The motor has four bolt mains and is designed for continuous WOT operation. Anyone know of any reason this won't do a great job?

 

does it have a carburetor? all the marine ones i ever seen were. dont really have a answer, i been told the same. i knew a guy that had a marine 283 and was looking into buying it for a s10 years ago and everything i found was it will work

 

It's a new crate motor. My nephew runs the shop and says everything will bolt up the same. I'll just have to change the oil pan and pump, slap the intake off my old motor on it and the rest of the stuff will bolt on too. It's the same block. When they say it will have higher low RPM torque does that mean it will get less MPG? I don't know.

 

Alrighty,i may be wrong but usually a boat motor has a different cam,since the run range is different then a automotive engine. Its made for best performance at 3k-5k. You MIGHT have to change the camshaft to a factory cam for a car. If you do have a higher cam,it means your motor will have no power at all until it reaches its peak at 3k. Say goodbye to gas.

 

Like a good nephew, he did send a new automotive cam along with it. I just wondered if the marine cam had more low RPM torque if that might not affect the mileage. I think before I go to all the trouble of mounting this engine that I will change out the cam. Good idea. Other than that do you see any problems with using this engine?

 

Does it come with the 4.3 marine intake? If so you'll have REAL fuel injectors, not a spider assembly & that means tapping into the wiring harness to fire the individual injectors.

 

It did not come with an intake manifold. I can take one off my old one and bolt it on. The block has all the same mounting holes and bolt patterns as my old one. The only actual differences are the internal ones listed above including probably the cam. Other wise the motors are the same. I am thinking the only modification I will need to do is change the cam. They say the marine cam closes the valves sooner than the stock one to minimize the possibility of sucking any water back up through the exhaust, which also increases the low RPM torque which may result in some bad fuel mileage. I just don't know how bad.

 

Well,thing is usually they are not built for low end torque,they are built for highend,they are designed to run around 3500-5500 rpm all the time. a 4.3 for a car is best around 1800-2500. Id change the cam out before id put it in. Thing is if you go carb,you can buy a performance cam for 130ish bucks and swap it out since you have too anyways and gain from it. Win for win!

 

Well guys, the weekend of the 20th will tell the story. I'll swap out the cam and see how things go. I really hope this thing works like it's supposed to. Should be a really good engine. I don't suppose anyone here knows if the water pump on a marine engine is reverse rotation like the automotive one?

 

I know Mercury puts the same size cam in there marine engines as the auto. You might wanta check with the manufacture before going to all the trouble. I know the valves are larger in the marine, don't know what issue that'll bring up w/automotive use. Are there machined threaded holes in the block for the water temp gage sensor, knock and oil pump switch on the marine engine?? I know the egr & vacuum system are totally diff on a marine...good luck with it..let us know what you run into...