Logo
FULL SITE MENU

Battery Info 1987 350

H

hippie

Regular Contributor
"Hi men, I have a 1987 350 CID, 260 hp that needs a set of batteries. Does anyone know the "cold cranking" amps needed for each? If I remember right they should be at least 650 amps each. Also, how about regular car batteries as opposed to "deep cycle" marine batteries. Thank you, Bob"
 
"Bob I like deep cycle since I

"Bob I like deep cycle since I power other items. If you are going to use a deep cycle battery also as a starting battery, it should be oversized about 20% compared to the existing or recommended starting battery group size to get the same cranking amps."
 
"If you are only going with on

"If you are only going with one battery, get a
combo battery, i.e. a marine start/deep cycle battery. Do not go with a deep cycle as your only battery.

If you are installing two batteries, install a marine start duty battery as your main battery, and a combo start/deep cycle as battery #2.
Do not use "both" position on the battery switch for anything other than an emergency, i.e., neither battery #1 nor #2 alone will crank the engine."
 
"I bought a marine starting ba

"I bought a marine starting battery @ 650 c.c.amps and a deep cycle marine battery @ 100 hrs for the bilge and electronics. Thanks to all who stated their opinion and Guy, I read your article and it was very informative. Thanks all, Bob"
 
"Bob:

What is the charging

"Bob:

What is the charging scheme used in your system? Also, are your new batteries the same 'chemistry' (lead-acid, AGM, etc)?"
 
"Makoman, The new batteries ar

"Makoman, The new batteries are lead acid. The charging scheme is alternator to the battery switch, where I can choose which battery to add current to inorder to recharge it. I can also draw current from either battery solo or both batteries at once (which is not recommended). The electrical is the older style Thunderbolt IV without points in the distributer."
 
I'd recommmmend NOT turnin

I'd recommmmend NOT turning the battery switch unless it has the field disconnect piggyback AND it is hooked up. Moving those switches with the alternator running has caused many an alternator to go for rebuild.

You may wanna look at ACR's (auto charging relay); these will let both batteries charge and still maintain independence when the engine isn't running.
 
"makomark, I have never heard

"makomark, I have never heard of a "piggyback" device. Mine is the standard switch that is circular in shape and colored orange. I don't recall the name but it's the popular brand you see everywhere. Do you have more info on this "piggyback system" ? Thanks again, Bob"
 
"Its a battery switch that ind

"Its a battery switch that indicates that it has a "field disconect" feature, although if you have a single wire alt, not sure how that would work. The danger is that the alt be running without being connected to any battery, i.e. DO NOT TURN TO OFF if engine is running. There are some switches that are arrainged... OFF-A-Both-B
These are probably safe to switch from A to B while running as you are guaranteed not to have the alt disconnected going from A to B. There are other switches that are A-Off-B-Both and they are dangerous in that you can go from A to B and transit "off", i.e., disconnected if not careful."
 
"Bob, Mine has off-a-both-b. I

"Bob, Mine has off-a-both-b. It must be set on one or the other to even start, so as you are saying "I have nothing to worry about". On off it is disconnected from both batteries and will not start. Thank you men for your responses.
(I finally got something right!). Bob"
 
"If you don't have 2 small

"If you don't have 2 smaller (~ 14 gauge) wires going to the battery switch you DON'T have the disconnect.

Whether it is safe to switch between the batteries is determined by the switch's construction...I'd bet few are make-before-break. You can test the switch with a test light. Hook it up to the common lug =on the switch and rotate the switch between the three battery selections. If the light goes out at anytime, DON'T move the switch with the engine running.

Robert - if its a 1-wire alternator, you can't hook up the disconnect without modification. When you're done, it will be a 2 or 3 wire type."
 
"This is a common misnomer!

"This is a common misnomer!
Most all of today's MBSS's (main battery selector switch) are "make-before-break" contact....., so switching banks causes no harm when the engine is running! (if concerned, do the test like suggested)

It's the passing through OFF (without field protection) that can cause alternator damage.

If you have an old MBSS, it would behoove you to replace it. (Perko offers among the smallest of contacts, btw)

Best to not crank on a single Deep Cycle battery. Cranking on Multiple Deep Cycles (in a House Bank for example) seems to not cause any issues. I know of several people, including mself, who do this on our Stbd engine with no problems at all. (I do not even have a dedicted cranking bank for my Stbd side.... only a large bank of Deep Cycle batteries)
I do, however, have a "combine" feature if need be!

Mark's comment re; the chemistry is important. Do not mix battery types!
Fact is..., best to not even mix age, size, condition, etc., within a group of multiple House Bank batteries..... standard, deep cycle or otherwise!
Best to replace all within this bank at the same time!


Bottom line..... if you have a single engine boat, you will want to have a dedicated "cranking" battery on # 1 (to be held in "reserve"), and your Deep Cycles battery(s) on # 2.
Never allow a bank to remain discharged for ANY length of time beyond reason. Manage these appropriately, and you will do just fine.
If you spend any time at all on the hook, you'll know how important this is.

."
 
"Maybe its just me, but I have

"Maybe its just me, but I have had great luck with the dual purpose batteries. I have a tender that keeps them hot but out of the slip they really get drained. Second year they are doing great. Guess we will see if they make that three year warranty.."
 
Back
Top