84 Dolphin Electrical Question

[djstory]

Hi All,

I took my 84 Dolphin on a 64 day, 8,000 mile trip this summer and it performed beautifully. Actually, my wife drove it most of the time as I was riding my bicycle from coast-to-coast. The motorhome was awesome, it was a comfortable home to our family of 6 and had no mechanical issues at all. But I got home, parked it for a month, and then tried to start it to move it- no start. I was able to eventually jump it, but only after leaving the cables hooked up for a while. Now another month has gone by and I can't jump it at all.

Any ideas on what could be wrong? I am not mechanically inclined, but it seems if it were a bad battery I would have had some issues during our trip. It sat for quite a while before our trip too and always started pretty easily. Can a battery just up and quit like that or is there likely some other electrical issue?

I wanted to check on this list before going out and spending the money on a new battery.

Thanks

Don

[fisherman120]

Hi All,

I took my 84 Dolphin on a 64 day, 8,000 mile trip this summer and it performed beautifully. Actually, my wife drove it most of the time as I was riding my bicycle from coast-to-coast. The motorhome was awesome, it was a comfortable home to our family of 6 and had no mechanical issues at all. But I got home, parked it for a month, and then tried to start it to move it- no start. I was able to eventually jump it, but only after leaving the cables hooked up for a while. Now another month has gone by and I can't jump it at all.

Any ideas on what could be wrong? I am not mechanically inclined, but it seems if it were a bad battery I would have had some issues during our trip. It sat for quite a while before our trip too and always started pretty easily. Can a battery just up and quit like that or is there likely some other electrical issue?

I wanted to check on this list before going out and spending the money on a new battery.

Thanks

Don

it could still be the battery, ive heard of brand new batteries up and breaking all the sudden whithout warning. i would take it out and take it down to autozone or checkers or where ever you have close and get them to test it for you before you replace it. If the battery is fine then you will know that there is a problem else where.

[T.A.J.]

it could still be the battery, ive heard of brand new batteries up and breaking all the sudden whithout warning. i would take it out and take it down to autozone or checkers or where ever you have close and get them to test it for you before you replace it. If the battery is fine then you will know that there is a problem else where.

Batteries that sit can trickle down to nothing. Get a good quality replacement and enjoy your RV. Costco batteries are awesome (hassle free replacement). Batteries, like people, Get weak with age. If ever you get to Mont., say hi!

T.jackson1963@gmail.com

[our85dolphin]

Don,

Don't be too quick to blame the batteries. It is true they might need replacing, but there may be a deeper problem.

We have a 1985 Dolphin that might be similar to yours. When we bought it about five years ago, we had various electrical problems with the engine battery. We replaced both house and engine batteries and installed a bigger (130 Amp) alternator, but we still had a problem with the engine starting the next morning, especially when we drove at night with the headlights (and all those running lights) on. This happened dozens of times. Also, once we had to fly away for several weeks when we were driving in our Dolphin, so we parked it at the airport long-term lot. When we returned, the engine would not start without a jump (we carry one of those battery jumpstart units).

Our rig has (not sure if it was standard equipment from Dolphin) a three-lug battery isolator. (It is located on our rig in the engine compartment, just over the driver-side tire.) The Dolphin actually needs a four-lug isolator. The thing I learned last year was that alternators need a little surge of current to get started--with a three-lug isolator the alternator does not get that and so the alternator will not charge the engine battery. So someone had put wire connecting the the engine-battery lug of the isolator to the house-battery lug of the isolator. This was an essential Macguiver-type repair because without it neither the engine nor house battery charges properly. But unfortunately, having the jumper wire between the lugs effectively is like not having an isolator at all (which means leaving just one house light on, or the water pump or whatever... will discharge both the house and engine batteries over a few days).

So, if you don't have an isolator or if you have three-lug isolator with the two lugs tied together, you have to be certain to cut the house 12-volt electricity completely if you are going to park for a long time. (You could remove all the 12-volt fuses to be sure.)

We have removed the jump wire. What we do now is use that wire to spark the house and the engine lugs together on the isolator for a second or two when we first start the engine. You can hear the engine starting to work harder when the alternator kicks in. Doing it this way means the batteries are charging, but the isolator works to keep the engine battery from draining if we leave a light on in the house (of course, that will drain the house battery, but the engine will start (remember to jump it) and that will charge the house up again).

I am planning on installing a switch in the cab to do the jump so that I don't have to pop the hood every time I start the engine. The other alternative would be to get the expensive four-lug isolator.

Maybe your problem is different. But before you buy batteries, etc. it might be good to take it to someone who knows electrical systems that you trust (not someone just trying to sell you stuff). We spent hundreds of dollars before we learned the problem could be solved with just one wire.

--Mark