1988 Club Wagon Ambulance, 7.3L IDI Diesel

With the batteries fully charged and the voltage guage showing 13 volts, when I turn the key to engage the starter, all power is lost, voltage guage drops down to zero, lights go out, and there is no action at the starter. Just had the starter overhauled and brushes replaced last year. This has never happened before, although it has seemed like the starter pulls on the batteries a little harder than it should.

Anyone know what this could be? Is it some connection grounding out the whole system? Im gonna check the connections to and around the starter as soon as I can, Saturday probably. But if anyone has an idea where I should start looking, or had a similar problem any input would be appreciated.

-Mike

 

A couple of things come to mind. First, your battery may show fully charged, but still bad and unable to supply the current needed for the starter. Have your battery load tested to be sure. Batteries are supposedly sealed, yet may still be low on water, which will cause problems too. Also check your battery terminals, cables, and connections for problems. Bad corrosion, loose connections, or damaged cables will be highly resistive and drop the voltage as well as current available to the starter.

I'd check your starter again, if your starter is bad, unable to turn the motor over, it will draw much higher current than normal, which will drop the voltage and give you the indications you have.

 

If the problem was "grounding out the whole system....With the batteries fully charged" you'd probably be posting about smoke & fire. It would be more likely from a bad ground. Check the heavy frame to block ground cable.

Mods to outfit as an "Ambulance" add a lot of extra high amp connections included in the dual battery/high output system. Any may be suspect.

However if its never had solenoid(s) replaced, that's where I'd look 1st. These are well known to eventually wear out, toasting the internal contacts. They're not expensive & easily replaced, just be sure to disconnect the terminals on batteries neg (-) 1st, or else you might just find yourself "grounding out the whole system" w/a spectacular flash & shower of sparks.

 

also you need to check the ignition switch
this is located on the column under the lower dash cover
M.

 

Best way is a volt meter from battery negative to a good ground on frame. Read voltage while attempting to start. anything over .2 volt is excessive resistance on ground cable. Clean post and contacts and try again or replace.

 

Thankyou everyone for your input. Couldn't see from the top and it was bolted on tight so i didnt look closer at first, but I found that the + terminal on the drivers side battery was partly melted! and not making good contact with the wire. Best I can figure its because i got one of those cheap bolt on replacement terminals, bolt came lose, wire started shaking around and arcing, melting the terminal. At least I hope thats what caused it. Ill only buy proper crimp on terminals from now on.

Also I found that part of the hard cranking was because the elbow that comes out the back of the injection pump was pluged up. I beleive its a one way valve. anyways I took that off and cleaned it out good with and air compressor and it cranks over way stronger now. Just thought I'd post that incase it helps anyone searcing the forum.

-Mike

 

its the ground or the park safety switch. i had this happen to me and it was [ because the shifter linkig is worn and sloppy] show it was in P when it really was in R.if its not one of those then check the battery amps not just the volts.

 

I have an 89 e350 jamboree by fleet wood 7.5 460 recently replace the ignition switch under dash , both battery's, fuel pump and fuel filter, when I turn key to start I loose all power

 

Start with the basics - check all battery cable ends, make sure that they are not the 'clamp on the cable' (held on by 2 - 1/4-20 bolts) replacements. If they are, toss 'em and replace with HD cables.

 

They are the clamp style had to replace them as some one cut original off what's an HD cables I got a negative cable replacement direct replace but what about the positive do I have to replace the entire cable ? Same as the negative ?

 

Does the positive cable go to a solenoid or directly to the starter ? Any truck parts supplier should have a good quality cable. A typical auto parts house may not have a cable with the correct wire gauge size.

 

So the positive goes to the starter selonide
So I replaced the selonide the positive cable and the negative cable grounded to frame same problem even if I jump the selonide it does the same thing ......
Is it possible the starter is shorting out ?
If I push the emergency start button using the camper battery (both new ) I won't loose power but it will not engage the starter .....

 

Without tools its possible to check for starter failure somewhat simply......

Turn headlights on, observe their relative brightness and then have someone else try engaging the starter. If they go exceptionally dim or fully extinguish chances are huge the starter itself has locked up, drawing so much power the lights go out. In this case its time to have the starter tested by a competent local auto electric rebuilder.

I do notice this seems to have begun only after the ignition switch was changed so that makes me suspicious if it was somehow installed incorrectly? That might seem impossible but the switch itself could be bad.

With a test light you could check the battery input lug on the starter itself, again having someone try to engage it. Assuming the cables are in good condition the state of the test light will show if there is power to the starter and whether its drawing too much current.

 

Ok here's the thing when I turn the key on I have no power it I push the emergency start button I get lights and powe if I turn key to start it all shuts off push the emergency start button all lights and power come back on if I hold the emergency start button and turn the key (linking the 2 batterys) no start but I do get a beeeeeep type sound (similar to the you left your key in ignition door open buzzer sound )
I did just pick up another ignition switch but will wait to install and change the starter based on what you are thinking

 

I have installed a starter still same problem. ..... the last thing in going to try is change the ignition switch after that I'm at a loSS ......any other ideas beside the ignition switch? ?