merc 470 questions

Lamont270

New member
Hello,

Newbie here with some questions about the merc 470. I have read alot of comments about it and it is 50/50, some love it, some hate it. Here is what I have done to my 470. New battery, starter, points and condenser, plugs, wires, cap, rotor, gimble bearing, all new bellows, shift cable boot, in line fuel filter, coil, and a carb rebuild. We have used the boat all summer with a few problems but never left stranded. Problems include, oil pan has pin holes in it which I have patched with JB weld for now, cam shaft seals in water pump are leaking out of weep hole, and of course the charging system. Right now the biggest problem is the charging system. My amp gauge was pegging out when i would go full throttle and the 50 amp circuit breaker would pop. So I started running with my lights on and my motor compartment blower on which helped that for awhile. Now the amp gauge goes crazy and the boat will break up and stall then it will restart and be fine for awile. I'm not sure if I should put the money into fixing it or if I should consider a repower. The boat runs great for the most part, it cruises around 26mph and full throttle @ 4300 rpm's I get 35mph out of it, and it is good on gas.

any thoughts?
 
If it were me I'd pull that harmonic balancer off and trash that whole charging system, water cooled regulator and all. Replace it with a one wire ,side mount, belt drive, external alternator. Just feed it with a fused, switched hot wire and it will solve that problem. As for the leaking cam seals , you can buy a cam seal replacement kit from Mercruiser, comes wih gaskets, seals and all. Just check the surface where the seals ride on the end of the cam and see how bad it is grooved. If it is, you can get a sleeve to repair it. Its really an easy fix. Ive done 3-4, only cost about 40.00. As for the oil pan look on ebay under 470 Mercruiser parts.They usually have some there cheap, the gasket will probley cost more than the pan! Check the web,there alot of good sites to order parts from. They're good motors , you'll get the bugs out. My boat had sat up for about 5 years and it took awhile to get it all straightened out but it was well worth the investment!! Good Luck! :party:
 
Oh, forgot to tell you, if you don't have one, check ebay for a Clymer Mercruiser manual. It helped me alot! Some good sites to get parts from are;Mercury Parts express,Sierra,Marine Parts express, Overtons,Aftermarket Marine, iboats.com, and even NAPA can get you alot of parts. I would suggest not to buy anything electrical from Advance Auto(I learned a good lesson on a starter). Good Luck!
 
Thank's C, I have done some research on what it would take to repair everything but one thing I have been warned about is if I pull the motor getting it lined back up requires some alighnment tools. I can pull the motor but I am a little leary about the alignment.
 
Its not that hard. Just put the shifter in forward and pull the whole outdrive off. When you unbolt the motor to pull it take notice of how the rear motor mount bolts, springs and felt washers go! When you reinstall it ,borrow or buy a Mercruiser Alpha alignment tool and insert it through the gimbal bearing into the coupler on the back of the flywheel. You can adjust the height of the front of the motor using the front motor mount. Coat the alignment tool with coupling grease and insert all the way in. Adjust the height until it slides in smoothly and has a uniform coating of grease on the small end of the tool. You'll see the splined teeth marks evenly all the way around the tool when it adjusted right. Its really easy. Do you have a manual? Look up marinemechanic.com or sterndrive.com, they have alot of good info!
 
sorry to have taken so long to respond to this thread, but I personally like the 3.7's. I've had a lot of good use out of them, but to be honest, parts atre getting scarce and they are getting expensive. The best ones to find are the late 80's 3.7 and 3.7lx, they allready had the better manifolds, bigger heat exchangers, gm style starter, and second generation mercarb on the 2bbl's. Before you ditch the charging system, if the balancer is good, and the stator checks out, why not try the rapair regulator, instead of grounding out the over voltage(hence the need for the cooler), the rapair unit cuts the feed voltage off till the voltage drops enough to need additional charging, just like any normal altenator. BTW, if any one needs one, I have a NOS balancer for a 3.7 thats never been installed for sale
 
Either the weights in the balancer have come loose or the regulator is about to blow up. I've had both happen at the same time,not good! Ended up going with the Alt.conversion kit then repowering with a V-6(still in progress). Which brings me to my next point. Got a newer oil pan and a bunch of other stuff if ya need them. :hi:
 
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