The exact battery rating shouldn't make any difference as long as cranking speed is adequate. Oddly, the factory manual does not really provide an exact spec for battery size but it does reference 600 and 800 CCA group 27 battery sizes.

I think your hard start issue is due to a problem with the fuel pump check valve as MobileAutoRepair suggested.

 

I can start my engine with either one, two or all three of my batteries, and each additional battery certainly turns the starter faster.

But the engine always catches quickly, even if the starter is turning slowly with just one old abused battery.

The throttle body temperature sensor and the check valve on the fuel pump probably have more to do with excessive cranking than a weak battery.

When my engine is restarted warm, the lightest tap of the starter kicks it to life. When overnight cold, under a second. more batteries make the starter crank faster, but do not appreciably decrease the time the starter cranks before the engine catches

 

More Batteries will just give you more Cranking Amps. It won't make the starter go faster, 12V is 12V and when you do connect batteries together they equalise to the same voltage.

Sure the van will run on a smaller battery, as a smaller battery is still quite big, it will just wear out quicker and cause the alternator to work harder.

The easiest way to check however would be to connect up another battery and see it it makes a difference, no need to buy a larger size.

The main point I would like to make is that these vans need to have a slightly better quality, than something you can just throw into a small vehicle. Also it is the way I like to have my vehicles set up.

One last advantage is if you run electrics while the van is not running gives you more buffer on running down the battery.

 

I really do not think that anyone is disputing that 12 volts is 12 volts. It's the reserve capacity that is important when the van is not running not the cold cranking amps. You are correct, the starter can only spin so fast which is one of the reasons I questioned your logic in the first place. The voltage regulator is located in the PCM on my van and that controls the output of the alternator.

So what is left? The amps and volts required by the distributor and the high energy components it contains. So the draw of these components is the only thing in question related to the battery.

Jason

 

Well, we made down to Florida. Of course we have been traveling at speeds of 70-80 mph. We left on Thursday night last week and stopped overnight in Dalton Georgia. The next day we headed into hurricane country and stopped in Ocala Florida to spend the evening. So by Sunday we were in the Fort Myers Florida area. Our best gas mileage was 13.7 mpg. Of course traveling at high speeds we knew we would not get the best mpg. We came down here to get married on the beach at sunset the first week of Sept. We are happy that we made it safely and we could not have asked for a more comfortable ride. The only incident I had was that the front blower motor needed at rap with a hammer to start it because the brushes occasionally do not make contact lol but the hammer seems to get it working. I did pick up a blower motor at advanced and we change it if necessary. Maybe on the way back we will slow our speeds down for a tank and see if our mpg improves. My honest opinion is that the Bosch Fusion plugs do not seem to be helpIng any with mpg. They do have a money back guarantee so no harm no foul lol.

Jason

 

If you were to place a voltmeter on the battery when the starter is cranking, you will see that the voltage goes down to the low 9's or even less during cranking.

So having 3 batteries providing their cranking amps most certainly allows the starter to spin faster because the voltage stays closer to 12.8 volts during cranking.

When batteries are put in parallel, it can take many hours for the batteries to actually equalize to the same state of charge. The cabling between the batteries and the internal resistance of the batteries determine the rate at which they equalize.

The voltage regulator is basically there to throttle back the alternator so voltages do not climb above ~14.5. The battery itself and the wiring between battery and alternator actually determines how many amps it can suck from the alternator.

So a larger battery which has had the same amount of amp hours removed from it can ask for significantly more amperage from the alternator until 14.5 volts is reached, so saying a bigger battery is better for the long term life of the alternator is just not true.

Having a bigger battery is better for the life of the battery, because it is depleted to less of it's capacity under the same loads while the engine is off.

Battery longevity is determined by the number of cycles, and the depth of discharge, and how quickly it is returned to a full state of charge, all other factors being equal.

Comicdon1, congrats on a successful journey.

 

Hello all, We successfully made it back from Florida a few weeks ago and are catching up on things and getting settled be back home.

I do have a couple of updates.

First the Van ran flawlessly with the exception of the occasional problem with the blower motor. As I mentioned before I solved that but rapping the side of it with a hammer when necessary. I have since replaced the blower motor.

We noticed when I drove at the lower speeds of 55-65 and drafted trucks our best mileage we can report is 15.1 mpg. Our second best driving at speeds of 70mph with some drafting averaged 14.7 mpg. We still seem to get between 12-13 mpg when it includes city driving.

On my list of things to replace are the coil, and I am going to start going through the vacuum hoses. After I replaced the blower motor, a day later I noticed the air conditioning would intermittently switch between the floor and the window defrost. At first I thought it was the resistor switch, but after looking I noticed a cracked vacuum hose that open and closes the distribution doors inside the van. I must of broken it when I installed the blower motor. I quickly wrapped it in rubber tape with repaired the problem and allowed it to function correctly again.

So the problem was solved but it reminded me that I need to go over all the vacuum hoses and replace them.

Jason

 

Perhaps the speedo and thus odometer are off.

Drive 60mph and start the stopwatch when passing a mile marker. The next one should be passed at 60 seconds.

GPS works too I hear.

 

I am currently running E3 plugs in both my 318 and 360 motors. Plugs cost around $6 a piece, well worth the money. I have a 96 Ram 2500 4WD ext cab with oversize tires and 5 speed manual trans 360 motor getting average of 21 mpg on highway and 18 city/country driving. i have several friends running same plugs with similar results all have gained at least 2.5 mpg. I have about 6000 miles on mine at this time and still running same as new.

 

I beg to differ! I've had so many v8 magnum Rams and vans from late 80s to most current and they always fire very quickly dodge has what's well known in custom build world as a high torque starter and are often integrated into high horsepower engines. Almost every 318 or 360 I ha e ow Ed even with crappy plugs wires etc will fire almost the instant you hit the starter if they're warmed up and have a good tune up and you go to start it most the time you barley hear the starter before it fires. In my opinion as far as tune up components go I've had better luck running OEM copper plugs with good wires cap rotor and coil as these ignition systems don't produce a very hot spark I've found running anything hotter than a copper will cause fuel knock over time and foul out the plugs unless you run premium fuel constantly. These engines have a very simple ignition system and unless you upgrade the ignition system and air intake it is pointless to run anything hotter than a copper. If you're looking for a simple upgrade to increase fuel economy slightly increase the spark plugs wires insulation by .5 to 1mm (jeggs.com) for a more efficient spark transfer specially the coil wire. Upgrade ALL GROUNDS they're cheesy in these models change your pcv and breather valve and run a Spectre or k&n air filter (I prefer Spectre) also run some marvel mystery oil to fuel every dozen fill ups or so and ad marvel mystery oil to oil every oil change this is my tried and tested formula for these engines I promise increase power and fuel mileage and noticably smoother like too smooth can't tell if it's running sometimes. I've owned over 20 of these trucks personally and dealt with hundreds I a Mopar fan boy for sure!