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Mercruiser 470 stator question

jadilla

Regular Contributor
So I just changed oil and new coolant, and found two free wires coming from the stator. They are wrapped in electrical tape at the ends and there are two more wires coming along with the power wire from the battery. All four wires are electrical taped at the ends, what should be right here? The engine runs awesome, but I guess this is the on board charging system. I have been starting the boat all week and letting it run for a while and the battery has still not died. I will have an onboard charger three bank system so if it takes a long time for the engine to drain the battery I will be fine. What do you guys think?
 
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I really don't have the money to buy an alertenator kit. They might have had one on it then probably took off when sold.
 
I really don't have the money to buy an alertenator kit. They might have had one on it then probably took off when sold.

It may cost more to get the original charging system to work then to buy and install a one wire altenator system. The regulators are very expensive and so are the stators.........
 
You should be able to find a used one. (alt Kit that is) There are enough boats around with these engines that have been converted.

Or have three fully charged group 27 dual purpose batteries on board when you leave the dock. One for the ride out, one for the ride back and one just in case. The alt kit would be cheaper.
 
That's a shame, the previous owner should have told you that he removed the charging system. kghost is right about it costing more to go back to the original charging system. I know it is expenive for the alternator kit but it would be your best bet at this point. ($300-$400 new) I personally wouldn't go out with that boat unless I had a charging system. Bilge pumps, engine, gauges, tilt trim, marine radio, fish finder, anything electrical will suck the battery(s) down pretty fast. just not safe! jmho. Take your time and do it right and you will feel alot safer. You don't want to be getting towed in! That costs money too.
 
True true.... I have a couple of fully charged batteries, but what I don't understand is the fact that the batteries have not died. I have one little automotive battery hooked up and it has not died. I sat there and let it idle for close to 25-30 minutes then bumped it up a bit to let it run and work the oil in well. I'm going to use it for short runs on the lake striper fishing, I guess I will go ahead and get everything done and as soon as I get some mullah accumulated I will go with the alternator kit.
 
True true.... I have a couple of fully charged batteries, but what I don't understand is the fact that the batteries have not died. I have one little automotive battery hooked up and it has not died. I sat there and let it idle for close to 25-30 minutes then bumped it up a bit to let it run and work the oil in well. I'm going to use it for short runs on the lake striper fishing, I guess I will go ahead and get everything done and as soon as I get some mullah accumulated I will go with the alternator kit.

All your powering is 7-8 volt ignition system and a few gauges. The battery have enough power to run the boat for half the day, barring a radio and use of the running lights.
 
All your powering is 7-8 volt ignition system and a few gauges. The battery have enough power to run the boat for half the day, barring a radio and use of the running lights.

Awesome, I will run the engine on one battery and run everything else on the other two batteries. I have a huge garmin 10 inch monitor gps i'm going to have to make sure I run on the other batteries.
 
Awesome, I will run the engine on one battery and run everything else on the other two batteries. I have a huge garmin 10 inch monitor gps i'm going to have to make sure I run on the other batteries.

Read post #6

I was more or less kidding. But it could be done if the kit is not in your budget.
 
I don't recommend running on batteries, ever. JMHO, that is for limping home only when something is broken.

NEVER us a automotive alternator from your earlier post, use only a marine alternator conversion kit. Fires and explosions tend to cost more then the hundred bucks you thought you saved.

Something else to look for. Previous owner probably had the voltage regulator fail and as you suspect had an alternator. New voltage regulators are $550-600+. Since you have to start over, check to see if the voltage regulator has been removed from the block & cooling loop, if not take it out and put a new hose in that "run" for a bit better coolant flow and fewer leak paths. A new Alt kit is HALF the VR price and if you can likely find a used Alt kit for probabably less, but of unknown condition of course. Maybe buy it from the orginal owner???
Number one killer of batteries is heat, it is hot in the bilge; number two killer, running down starting batteries like deep cycle batteries, they are not designed for deep discharge activity which is what you are asking to do. That thing will be junk before you know it. Be safe and save some long term money, you will have a much better summer and you will get more life out of your battery you already have with an alternator.
 
You need to be running the bilge blower at a minimum of 3-5 mins. before every start and 5 mins. after fueling which draws the battey down. It is also a good thing to run the blower while under way to remove latent heat gain from the dog house. Your carb will appreciate it. A few boaters have gotten alternator brackets from junked cars and made some modifications to the mounting bracket holes...it will save you some money. The 110 amp marine alt. is good to have for the charging power but not a necessity. A 65 amp marine alt. will suffice and save some money...make sure it is a single wire self exciting type. Make sure you size the charging wire to match the alt.'s output! I prefer 8 ga. wire for 65 amp. and 6 ga. wire for 110 amp.
 
jadilla, when I first rebuilt my engine, I was in the same boat (lol). But, never attempted to launch until I installed the after market alternator. I too ran the engine on the trailer, but for a much longer period of time at around 1000-1500rpms. Of course, with muffs and water running. After about an hour and a half, I started to smell unburned fuel vapor coming out of the exaust system, then when I would try and throttle, it would either backfire and or bog with very little power. Also noticed after running this way a few times, the plugs were covered with black carbon. I did this for breakin purposes only and to see if the engine was going to hold together after rebuild being it was the first time I had rebuilt one of the 470's. I am not saying that my battery at that time was up to par but all the same it went flat after about an hour and a half. If you could get a 65 amp marine alternator, you could possibly build a bracket to mount it. But! The problem arises as to allignment issues from the crank pulley to the alternator itself. If you have power steering, then there would be another pulley to figure into the layout. You would have to make sure that the alternator mounting bracket is afixed to the front of the motor securely. You could probably copycat and fabricate but the question arises as to which one you copycat. Dont forget that the block is aluminum. The timing cover is aluminum. There have been posts about guys making there own brackets but shortly after a few months posted about broken timing covers, pulled threads, problems,problems,problems. (mostly home made brackets but not all) Some problems may have been caused by simply a poor design and some because of improper torque at the front of the motor and also misallignment of pulleys causing vibration. Breezeworks 470 talk sells an alternator kit. Talk to Kevin, the moderator. Breezeworks 470 talk is a forum dedicated towards the 470 owners and there are some great people that are willing to help you. Not forgetting this site either! These guys are great too! Whatever you decide to mount up, just make sure you take a straight edge across the front of all pulleys after installation so you are not running crooked with your belt. You will know right away and smell burning rubber if belt is not running true. Your new alternator may also heat up and fail prematurely if not running true. To tell you the truth, I paid $400 for the one I got and it was fabricated (welded) crooked as a dogs leg. The alternator diode did not work when brand new. A buddy helped me fix the diode problem, but the point is: I was totally dissatisfied with the product and actually had to repair a brand new product to make it work correctly. There are several manufacturers but again you will have to determine what is best for you. Just be careful when installing the kit also. Read all of the directions and follow them to a tee. You'll get it, just takes some time,some work, and of course some money! good luck, Tom
 
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Hey, it's a start! Alot of Amperage. I don't think you need that much. jmho. I was going the same direction as you when trying to choose a suitable system for my boat. My setup came with a 65 amp. which is overkill on my little boat. jmho again. Some guy was talking about not needing that much power on another site especially for a little boat. For the price, I would say go for it! Delco is alright. just remember, if you are going to eventually buy a kit that does not come with an alternator, it would have to have the same bolt pattern or setup. I think most are the same but don't assume anything. Maybe someone on this site could add to this to save you any bother. Look on ebay under Mercruiser 470 and go through all the parts until you locate the aftermarket alternator kits. There is a high mount setup deluxe package. (that is what I bought) It is expensive, but I really like the mounting assembly. It is strong as heck and there are mounting bolts that attach into the iron head. Like I said, I had problems with my installation but after I debugged everything, it works very well for what I need. I think the place is in Marysville Washington. (Hunn Finn?) After you see it on ebay maybe google the Hunn Finn site. It should come up. Maybe make a deal without alternator. I think the alternator that he provides are pretty much low budget if you know what I am saying? good luck, Tom P.S. I wasn't sure if you had power steering or not? Mine has power assist steering and it will probably make a difference on your selection options.
 
I have twin 470's one has power steering the other now has a delco 55 amp marine 1 wire i found for <$60 new. There was an existing mounting bracket and I bought an adjuster bracket from napa and all is well. I do however still have the existing stators dead ended, thinking if it has no path it makes no power. Am I being dangerous? Does anyone else have their stock charging system abandoned in place?
 
I have twin 470's one has power steering the other now has a delco 55 amp marine 1 wire i found for <$60 new. There was an existing mounting bracket and I bought an adjuster bracket from napa and all is well. I do however still have the existing stators dead ended, thinking if it has no path it makes no power. Am I being dangerous? Does anyone else have their stock charging system abandoned in place?

I have read about two issues here regarding leaving the 470 stator on the engine following a conversion. One of course is the fact that even though the remaining wires are taped off and dead ended or whatever the potential for a dead short is possible because the stator is still making electricity. Secondly it is recommended that the stator itself be removed. A "PITA" job. If a magnet comes loose from the stator, which is common I guess, it can take out the cover and wipe out your timing marks etc.

Dennis
 
Thanks Dennis, I plan on removing them when I pull the engines for resealing. Just too hard for me to do in the bilge with 2 engines. (as are the gaskets&seals)
 
I have a 1978 Bayliner Victoria. I bought it when it had the factory charging system installed but the regulators were bad (actually melting). I abandoned (dead ended the system) and put in a single 55 amp marine alternator which has worked well. I still have electrical issues though. When I use the bilge blower it draws excessive current and if I leave the shore power connected the anodes need replaced in a few months. Also, some days it runs great at 40mph plus and others it wont even plane. I believe this to be sticky distributors not advancing. Also it seems to crank slow on either engine when starting. I have no reference though as all my modern vehicles crank much faster. Are the 470's notoriously slow crancker's or do I have an electrical issue? I am only running 2 deep cycle batteries and the system can accommodate 4 so I am missing the starting batteries but I thought 2 deep cycles could handle the job.
 
The first thing I did is sand all my battery and starter connections to no avail. (plus they looked pretty good to start with) I will ad starting batteries even though i have two deep cycles I need more. I do have a volt meter and the performance issue seems independent, however the engines will fail in a manor resembling vapor lock and I have yet to determine if that is a voltage issue. (let them sit for 45 min and right back to life. Both engines still crank. I am running the alternator through the existing charging circuits and since I am producing less than factory amperage the wiring should be good. I am going to start simple and drown both distributors with WD40 and see if that loosens them up. Batteries may be past their prime but issues are since they were new. I understand that 55amp alternator is minimalistic but as I mostly use it as a live aboard when I am working out of town I will see about more charging system later. (a bigger alternator on the power steering side.) Thanks for all the help guys, I am famous for overlooking the obvious.
 
Good Idea about the ground. See what I mean by overlooking the obvious... Anyway I have not upgraded from the points ignition as I do not wish to invest any real money right now, just time as I am not working steady. Today was my first in 28 days out of work, I got 4 hours today and hoping for 8 tomorrow and possibly 40/wk for a while... We will see.
 
bobsquatch, you asked if the 470's are slow crankers? The answer is yes if you do not have really good batteries, cables,grounds etc. I think #4 wire would work best. Just because the wires look good from a visual perspective does not guarantee that there is not any degradation within the wire jacket. May not be the case but figured I would throw it out there. Also, which starters do you have on the engines? The Delco's with the built in solenoid are alot better than the older style starters with the remote solenoid. Forget what the earlier brand starters were. I think prestolite? There are too many connections that can get corroded on the older setup which robs alot of amperage which in turn can cause a dogging when starting. How old are the starters,cables? I cleaned up my Delco starter when rebuilding and have had no issues in two years. Have you ever pulled the starters and attempted to take apart and clean,inspect brushes,field, post connectors. That will give you a weak crank symptom. Also, try and keep the starting battery cable as short as possible and clean as a whistle at the ends. Dialectic grease might help to coat the connections just to slow down corrosion after everything is nice and shiny again. Excellent grounds are a plus also. I have more than one on my boat. maybe overkill, but it gives you a chance if one gets weak or fails. good luck, Tom
 
...When I use the bilge blower it draws excessive current...
Check the wiring for internal corrosion...if it is black coated copper it is corroded and should be replaced. New blower motors draw less amperage.

I am running the alternator through the existing charging circuits and since I am producing less than factory amperage the wiring should be good.
You stated the regulator was melting. That would have affected the charging circuit wiring. Try changing the alternator output and ground wiring to 8 ga. finestrand copper and you'll see an improvement.
 
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