Evinrude 9.9 - 4 bladed prop?

[Sumner]

I think having an extra motorcycle battery if you allready have two deep cycle batteries is a waste.... ...

The problem is the batteries are up under the v-berth/sink and my wiring might not be adequate from there back to the outboard and I don't know if I want to replace it as I have a fair amount of money in it now and a larger gauge wire is more expensive than the battery. Walt ran 4 gauge between the two and I have 8. If I had the 4 for sure I wouldn't get the second battery.

I also want the outboard hooked to at least one of the batteries at all times so I don't take a chance on blowing the diodes in the alternator and with the off-1-2-both switch I have now it could accidentally be in the off position and I want to stay with the switch at least for now, so I have charging options from the generator and the solar panels.

$35 for a battery takes care of a lot of the above ,

Sum

Our Trips to Lake Powell, UT - Kootenay Lake, Canada - Priest Lake, ID

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[walt]

Sumner, where did you get your prop re-pitched, what did it cost? Im thinking maybe getting the 5 pitch changed to 6.

My batteries are all the way forward as possible in the boat - two big six volt golf cart batteries and I have 4 gauge wires running the entire length of the boat to a break out box in the Laz for the outboard starter - seems to work very well. Batteries up front also help with trailering weight distribution.

The other really important issue about the 8 gauge wires with batteries up front and the outboard in the rear.. I saw over 50 amps when I first started the outboard (it was brand new, temps just over freezing). I normally see maybe 35 amps, don't know what the very peaks are since my meter does some averaging. Peaks are likely higher than what I see on the meter.

There should be a fuse right near the battery in case you short the main 12 volt wires (in my case, they run the length of the boat). The fuse needs to blow before the wires melt their insulation and possibly fuse together - ie, the fuse prevents some bad stuff from happening.

In my case with the 4 gauge wire, I can put a fuse in which is large enough to handle the outboard starting current - but small enough to protect the wires (90 amp in my case).

With 8 gauge wires and a 26 foot run... its a little iffy picking a fuse which does what is described above.. Ie, the smaller wires require a lower amp fuse - and it may need to be so low that it blows when you try and start the outboard.

What Sumner is doing gets around this problem..

 

[Sumner]

Sumner, where did you get your prop re-pitched, what did it cost? I'm thinking maybe getting the 5 pitch changed to 6...........What Sumner is doing gets around this problem..

Walt call Midwest Propeller Service at 913-782-0213. They are in Olathe, KS......

http://www.midwestpropeller.com/

...and they charged me $15, but I think he said that was a little less than if you just sent them a prop. The prop was $80 and they re-pitched it from a 9 to an 8. He could of gone more, but that was what he recommended. They did a great job. It looks like it came from the factory that way. Call them and talk to the "old man".

If they can do the 5 to a 6 that might be really nice, maybe about perfect for our situation. Keep me informed.

On the battery thing I've thrown it around in my head laying awake at 3 am :cry: and with my combination of the generator, solar and the two batteries and now the outboard it might be the easiest solution at this point at least. I wish now I would have done the 4 gauge up front like you did, but at the time I forgot about the outboard. Other than that it has worked fine. I want to rewire the boat, hopefully this summer and maybe I'll still do that down the road.

I have one motorcycle battery that I bought for my lakester and since it isn't done :cry: we have been using it to inflate the zodiac. I'd like to just keep it for that, so I guess I'll be getting a second one.

c ya and let us know if they can re-pitch the 5. Also while you are talking to them ask them if they could re-pitch the 7 four blade down to a 6,

Sum

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[timebandit]

I can't say for sure what size the wire is but here is my story.

I am a professional mechanic and I have a remolt starter switch from Sears. This switch is designed to connect the car battery + to the key side of the starter sol. so you can crank the motor over while under the hood.

Now what I use it for is to go from the battery to the hot side of motorcycle starter bypassing the sol. and a bunch of safty interlock switches to crank the motor with or without the ign. on.

The wires on the switch are about 8 feet long and cant be over #12 gage. I have heated the wire when cranking for 15 seconds.

Some things to think about----

The power to start this motor is just that, to turn the starter. It does not have to run the ign. system or an electric fuel pump or a computer. It just has to turn the motor over so 11.5 volts will start the motor.

If you have enuff 8 gage wire to run a 35 amp alt.to the batteries up front (20 feet) you won't over heat the wires starting the motor for a few seconds.

When you size your motorcycle battery remember that motorcycles that ran a 25 amp charging circuit used the 25 amps to run a headlight and tail liight and ign and instrament lights and maybe more so that the amps to the battery were about 10 amps.

Mororcycle batteries have just one vent and tend to vent acid when over charging.

I would use a lawn tractor battery even if it is a little bigger if you just gota have a battery back there.

 

[Sumner]

.................If you have enuff 8 gage wire to run a 35 amp alt.to the batteries up front (20 feet) you won't over heat the wires starting the motor for a few seconds........................I would use a lawn tractor battery even if it is a little bigger if you just gota have a battery back there.

I'm not so worried about overheating the wires as I am about having good current and voltage to the starter. I have a feeling the #8 wires will be ok and if the breaker doesn't trip and the outboard turns over good I'll leave what I have alone and concentrate on the wiring in the rest of the boat as it is in pretty sad shape.

If I have a problem then I'll decide if I want to increase my wire size from the stern to the batteries or go with the battery option. I would just have to add one new wire as I could use the 2 #8 wires for either the positive or the negative side in parallel.

If I go with the battery it will be with a ventless AGM battery like the one I have now.

Thanks for the input,

Sum

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[timebandit]

Where do you get your batteries and what size is it, that is cheap for a agm.

$35 for a battery takes care of a lot of the above ,

If I go with the battery it will be with a ventless AGM battery like the one I have now

 

[Sumner]

Where do you get your batteries and what size is it, that is cheap for a agm.....

I got the AGM down at a battery discount place, batteries is all they sell, in Phoenix that a friend took me to (but for a place as cheap or cheaper on the Internet look at the link further down this post).

On checking I think the size AGM I have now might be too small....

..... It is the battery the arrows are pointing to in the race car. The other larger one in the picture that isn't an agm is for starting and to run the water pumps for engine cooling and the turbo inter-cooler. I looked and the smaller one is only 5 AH. I bought it for the computer and data logger on the car and it only has to supply power for 5 miles.

I looked and Tohatsu recommends a 40 or 70 AH battery for the 9.8 HP. I can't figure why it has to be that size as the outboard is under 250cc and looking at motorcycle batteries here.....

http://www.batteryspec.com/

......it looks like a lot of the motorcycles, snowmobiles and jet skis are using batteries in the 10-12 AH ratting and I'll bet one of those would work. They have an AGM for about $40, which includes shipping.....

http://www.batteryspec.com/cgi-bin/cart.cgi?action=link&product=20

...that I would think would work. Notice the word 'think' , because I can't figure out why Tohatsu recommends such a large battery unless they are thinking you are going to also use it for lighting and such or for fears of overcharging a small one, but I would think the alternator wouldn't do that.

But saying that I think the following is a better option if I have to do anything other than what I have now. I forgot that I had found this place......

http://stores.ebay.com/Genuinedealz...84430QQ_sidZ779049QQ_trksidZp4634Q2ec0Q2em322

....where I can get their cheaper #4 tinned cable for $1.23 a foot and the better more flexible #4 tinned for $1.55 a foot. So I think that buying that makes a lot more sense now. I could use the #4 for the positive and the 2 #8 wires I have now for the negative leads from the stern to the batteries up front. This would also make my charging circuit a little more efficient with less line losses. I'd get the better more flexible cable.

Still as I mentioned before I'll try what I have now and see if it works before I do any of this.

c ya,

Sum

Our Trips to Lake Powell, UT - Kootenay Lake, Canada - Priest Lake, ID

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[timebandit]

"I looked and Tohatsu recommends a 40 or 70 AH battery for the 9.8 HP. I can't figure why it has to be that size as the outboard is under 250cc and looking at motorcycle batteries here....."

The outboard motor has a set of coils to provide for its use and more in the charging circuit.

I think the charging system is like that of a plug in battery charger of say 10 amps.

It seems to me that batteries like about 10% of the amp hour rating for charging or in the case of a 5A battery about 1/2 amps.

The engine recommendation for battery size is more for charging than starting.

You are planning on keeping the alt. on the bussa, right? You will need about 20A to run it and it won't run with less than 12.5V.

 

[Sumner]

........You are planning on keeping the alt. on the bussa, right? You will need about 20A to run it and it won't run with less than 12.5V.

Yes on the alternator, so it will most likely supply the stock busa computer. With the turbo at this point I'm not sure what I'll do about the increased fuel needed for it. I'll probably wait until the car is more finished and see what is best then as all of the computer stuff is changing rapidly.

Some of the guys use the stock computer and stock injectors and then add a second set on an extended runner going to the plenum after the intercooler and run those on a separate computer, like megasquirt that kick in under boost and are boost referenced. This would be the cheapest approach and I'd like to end up with megasquirt on a couple other vehicles I have, so doing that I'd just have the learning curve for one setup.

Even if I don't run either computer off of the smaller battery it will get used for the data logger. I had to add one on Hooley's Stude as it would drop out while we were firing the motor and the voltage dropped and then if you forgot to re-set it, no data :cry:.

c ya,

Sum

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