Community Forums

wolfe10 · 12-26-2014, 06:59 AM

If voltage AT THE BATTERIES dropped like that when you turned the key to the first position (to turn on the Intake Manifold Heater), the batteries are bad. If the big voltage drop occurs at the engine or dash, but not at the battery, more likely to be a corroded or loose connection.

Yes, if this occurs only when the starter is engaged, it would be something else (engine, starter, etc), but first step is to verify water level in batteries, fully charge the batteries and have them load tested.

Brett
2003 Alpine 38'

Algoma · 12-26-2014, 07:05 AM

A 2000 Alpine will have an ISC engine and it sounds as if the starter motor is not turning. The fact that the voltage drops when you try to start implies current is getting to the starter but it is not turning, maybe it is jammed. If you have a clamp meter try measuring the current the starter draws. If it is only a few amps then you have a bad connection somewhere.
Try starting with the generator running to ensure the batteries are charged up.

DMTTRANSPORT · 12-26-2014, 07:11 AM

6 year old batteries....I would start right there....

Pds47 · 12-26-2014, 07:14 AM

If batt voltage does not drop below 10 volts while cranking the engine the batts are OK does the engine spin over or not ??? inquiring minds would like to know

Lindenberg · 12-26-2014, 07:59 AM

1). What exactly do you mean "won't turn over"? Do you mean the starter is not spinning the crankshaft, or the starter is spinning the engine, it just won't start?
When I turn the key the starter doesn't do anything.

2). Is your motor a C8.3 or an ISC8.3 (what year)?
My Motorhome is a 2000 Alpine.

3). If outside temps are below freezing, are you using your block heater?
I'm in Southern California and it is in the 60's

Also, when I press the "Boost" switch to tie in the house batteries the voltages do increase. The boost feature is working so I don't believe it is only the chassis batteries getting old. When my chassis batteries were failing 6 years ago the engine wouldn't turn over but pressing the boost butting started it right up. This is why I suspect something else is going on.

Lindenberg · 12-26-2014, 08:36 AM

Quote:

Originally Posted by Dennis4809

Had the same situation with the "loose cable" except we were at a rest stop on I-39. Tightened the nut and everything was fine. Now use lock tight.

What nut(s) did you tighten? The only connections I haven't checked are on the starter itself. I'm not sure how to get access to the starter connections because of it's location.

SteveS · 12-26-2014, 09:47 AM

If you are getting 10.8 volts at the starter (through secondary solenoid) then it sounds like 1) starter is jammed, or 2) starter brushes are shot, or 3) starter winding is open.

tiredvet · 12-26-2014, 09:57 AM

I had a no start issue a few months back and after checking out the starter,alt,bats and connections it turned out to be a bad ground fuse.

Lindenberg · 12-26-2014, 10:04 AM

Where was this fuse located?

twinboat · 12-26-2014, 10:23 AM

Before you start tightning battery cables on the starter, unhook the batteries. If not, you may be doing some welding down there. Been there done that. It`s tough on the wrench`s

Lindenberg · 12-26-2014, 11:36 AM

I'm getting closer! I tightened all the connections on the starter solenoid and the starter. Checking the voltage on the output of the solenoid on the starter when trying to start the engine showed almost nothing. Not even 1v. Is it safe to assume the start solenoid is the problem?

I've read comments where you can hit the starter with a rubber mallet to encourage the starter to start. What do you hit, starter or solenoid? Is this to get the solenoid to make better contact?

Lindenberg · 12-26-2014, 11:36 AM

I'm getting closer! I tightened all the connections on the starter solenoid and the starter. Checking the voltage on the output of the solenoid on the starter when trying to start the engine showed almost nothing. Not even 1v. Is it safe to assume the start solenoid is the problem?

I've read comments where you can hit the starter with a rubber mallet to encourage the starter to start. What do you hit, starter or solenoid? Is this to get the solenoid to make better contact?

MnTom · 12-26-2014, 12:39 PM

What happens in the starter solenoid is every time you engage the starter the contacts arc just a bit when they open. Over time it burns one side away. That causes high resistance making the contact get hotter and burning more making it get hotter and burning more and..... well, you get the idea. If you take a hammer and tap on the solenoid you can get the contacts to make enough of a connection to get it started. This page will give you an idea as to what they can look like. STARTER CONTACT PICTURES I don't know if it is the same starter on hte 5.9, but if so the parts can be had here quite reasonably: Larryb - LarryB's Cummins & Dodge Denso Starter EASY rebuild kit 94-06

Algoma · 12-26-2014, 12:42 PM

Based on the layout of my coach, the ground fuse is in the service bay at the rear on the passenger side. There was a recall that raised the value of this fuse and on later coaches it was eliminated altogether. So it was a known problem. Did you check the starter solenoid in this bay first? Mine stopped working one day, you could hear a click but it did not make contact. I now carry a spare, NAPA ST85.