Mercruiser 470 engine swap

"what options do i have for re

"what options do i have for replacement of a 470. I like its power, but its not dependable. I am scared to go to far off shore. The problem is usually temps climb at near full throttle, but not all the time ,strange."

"I don't think there is a

"I don't think there is a "drop in" replacement for this engine. It will require new mounts, plumbing & wireing. That translates to time and money. Its easier to get your 470 going right. You might as well join half the people posting lately trying to get their 470 running cool!!!It can be done, mine runs great, nice and cool even on a 3 inch heat exchanger.
Chris"

"Wow, how many 170/470's d

"Wow, how many 170/470's did Merc sell I wonder?
Seems like they are the most common engine on this site needing some kind of help.

You may want to consider dropping in a 220 hp 4.3 V-6. It should fit, and should work with your existing drive. Your leg ratio should be 1.84, right?
You will need to get a Y pipe exhaust collector, and relocate your front engine mounts. Most of the plumbing should work, and the standard 10 pin engine plug will plug and play as far as wiring goes. Does your 470 use the 10 pin plug?
What year is it?
You may be able to find a complete 4.3 engine package on ebay, or a marine salvage outfit.
The 4.3 package will weigh a little more, but you get 50 more hp for your trouble.
Rod"

There is no doubt about it Rod

There is no doubt about it Rod you are are a horsepower fan.
The 470's Generally are a good motor but they can easily be let down by the accesories that are bolted onto them as can any engine.
Cooling systems and Charging systems seem to be the main dramas but get those sorted out and you will have a reliable and fairly fuel efficent engine.
From what you are describing I would be closely looking at the heat exchanger for a build up of crap in the cooling tubes.
Cheers
Peter C

"Peter, you had me at "hor

"Peter, you had me at "horsepower".
No doubt about it, there is never too much power. It's kind of like having too much fun, too much money, too many toys. There is no such thing!!
On a more serious note, I just figure most of us can always envision some kind of upgrade that improves performance, by a little or a lot, so why not go for it? It must be a guy thing.
Just my thoughts.
Rod"

"I spun a rod bearing in my 47

"I spun a rod bearing in my 470 a year ago and thought about dropping in a 4.3. I even picked up a y-pipe with the correct flange bolt pattern (there are 2 types). The flange was about 5" short of bolting up to the transom mount and the top side hit my power steering. I have a 1987 alpha 1 generation 1 with 1:84 gear ratio and without some major work, a 4.3 wouldn't just drop in due to exhaust pipe problems. Otherwise, the size of the engine is very close and most other aspects would work well. The front engine mounts would have been no big deal at all. I found the best route for me was to just turn the crank and put in new bearings. Had it all apart and made sure the cooling system was clean and clear. Been running fine this year (so far)."

"decided to stay with the 470.

"decided to stay with the 470. My main question is why would it overheat one time and not another. On one trip to the outerbanks i put at least 70 miles on it with no problems, but 2 months later it overheated 200 yards from the dock. When i noticed the gauge climbing i backed off the throttle and it cooled down quick ,i then accelerated to half throttle and then 3/4 and the temp stayed normal ."

"Sticky thermostat or a bit of

"Sticky thermostat or a bit of a blockage at your water intake screen on the outdrive.
Just in case fit a new thermostat, if it has stuck once it will stick again at some time.
Regards
Peter C"

"rod ,about how many 470s out

"rod ,about how many 470s outthere? as much as 460 ford engines the head of the 470 is a ford 460 head ,had one ,swapped it faster than a tuna chased by makos"