Community Forums

MikeandJan · 04-04-2017, 01:13 PM

My coach is stored through the winter in a lot with no external power. Usually I go over every month or so and exercise the generator. Occasionally I'll start the engine also. Getting ready to do some traveling so I went over to the lot several weeks ago and the engine would turn over barely for a second or two but not nearly enough to start. The chassis batteries were at 12.4 volts so I thought they might need a little boost - tried with the house battery booster switch. Same result. Cleaned all the battery terminals, although they looked good. I charged the chassis batteries by running the genny and plugging in a battery charger. Got the chassis batteries to 12.75V. Now engine starter seems to do nothing. I'm thinking I probably need to call a mobile service for a new starter. Any other suggestions? I can't get under the coach and have no tools or skills to change the starter. Thanks.

Kiawah · 04-04-2017, 01:40 PM

How old are your chassis batteries? I would suspect them first.

You taking their voltage after just having a charger on them is not an accurate reflection of their SOC. Measure their voltage after a couple hours of rest. See if the batteries are holding a charge, or is they have a cell going bad and the voltage has dropped.

After you check the voltage, you may also try wiggling your key a little. If the ignition switch is going bad, it may not be making contact for the start switch, and not engaging the solenoid for the starter motor.

Unplanned Tourist · 04-04-2017, 01:54 PM

Make sure the battery connections are good and clean on Chassis batteries. Have someone try to start it while you read the voltage at the batteries. This will tell you if the batteries are bad or the starter or wiring to it is bad. Could be a connection on a relay as well.
Good Luck.

8.3Oilbuner · 04-04-2017, 02:13 PM

Hi MikeandJan; I agree with Kiawah and Unplanned, you say the engine did turn over, and after you did the boost, the engine still did crank. Even with the gen running charging batteries, you depleted a large amount of the amperage reserve in the chassis batteries. Depending on outside temp, the grid heaters were in use on the engine while you waited for the wait to start light went out. Then you go to crank the engine, huge draw on the batteries. Even batteries in fairly good condition will take some time to recover after that huge amperage draw was put on them. Like others have said, could take hours to recharge. How old are your batteries? Have you checked specific gravity of the batteries when fully charged to see what shape they are in? I would do like others have said, get the batteries fully charge before going the bad starter route. Hope this info helps you get going. Also note, batteries can show 12.4V or higher but, if their amperage capacity has been compromised, you don't have enough to turn over that 505 cubic inch diesel engine.

MikeandJan · 04-04-2017, 06:58 PM

The charger was on the start batteries for 6 hours. Unfortunately, they are sealed no-maintenance batteries and I don't believe there is any way to test other than voltage. They were in the coach when I bought it 1 year ago and they look like new - no dates or anything. While the engine turned over it was just the ugghh like you hear with a dead battery. I'm going to look at it tomorrow and check the voltage after letting it sit over night. I might just buy new batteries to eliminate the unknown. I did talk with Cummins today about mobile service - they should change their Coach Care to Coach Don't Care. Told me that they only do mobile service for OTR trucks and I would have to have it towed to the shop which is 33 miles away!

mackwrench · 04-04-2017, 08:04 PM

The batteries can be load tested, where ever you buy them should be able to load test them....
From what you've described, my guess is one or both are bad.

Ray,IN · 04-04-2017, 10:13 PM

I assume you've already removed, cleaned and re-tightened every cable connection; the next move might be measuring resistance in your cables. Cables and terminals can corrode inside the covering and inside terminals, you can't see it but it can be found with an ohm-meter(disconnect both ends first)

barmcd · 04-05-2017, 06:35 AM

I had a similar issue and it turned out to be the battery. The static voltage was almost 13 volts, but the cranking voltage was very low. You have to measure the voltage when the starter is engaged. It was only a year old and under warranty so I took it back to O-Reilly and it tested bad. I got a new one under warranty. I'd at least haul it down to an auto parts store and have them test it.

MikeandJan · 04-25-2017, 07:28 PM

Thanks to all of you who provided advice. I had the batteries load tested - one was OK and the second was marginal. I replaced both with Interstate 1100 CCA batteries and had the same result from the starter. I think I mentioned that both Cummins (23 miles) and Cat (9 miles) said to have the coach towed to their shop. Getting the coach out of the campground storage lot with a wrecker would be a challenge as well as an unneeded expense. IF it were an OTR truck, both allowed as how their mobile mechanic would take care of it. A good local mechanic (who has done work for me before) finally had time to take a look and confirmed that the starter is bad. The new starter arrived today and hopefully will be installed in a day or so. The weather has not helped with over 8 inches of rain in the past 3 days. Thanks again. I'll update when the problem is resolved.