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Renenite · 10-24-2015, 10:35 AM

I have a 1996 Bounder F53 chassis, 460ci, 30'. Class A
I'm having intermittent problems with starting, happens a few times but it seems the battery hasn't enough juice to turn it over & it needs a 2sec jump to start, then works fine? I think it's in the solenoid, I have to play with the key sometimes too. I want to replace the starter solenoid, where is it?
Then I reading something & they said to replace the starter relay 1st????
Wheres that located? I know there's a ignition relay in the battery control box, is that the same? Could sure use some help, thanks.

subford · 10-24-2015, 11:39 AM

The starter solenoid is mounted on top of the starter.
But the starter relay is mounted on the side of the dog house on the drivers side. See image below.

No the relay you speak of in the fuse relay box that you are calling the battery control box is the PCM Power relay. The PCM Power relay is controlled by the Ignition switch.

Before you replace anything the next time it does it pull up on the shift stalk and see if it will crank then. If it does you may have a problem with the shift linkage to the NSS on the side of the transmission.

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Renenite · 10-26-2015, 02:06 PM

Thanks Bill, I want to replace both, I will ck the shift stalk too, there's 78,000+ miles & it's almost 20yrs old.

2000 Damon · 10-26-2015, 03:19 PM

I have found in a starting system that is intermittent is either a poor ground to the motor, starter relay contacts burnt, or a starter armature bearing worn out causing the armature to stick to the commutator . The starter solenoid just slings the gear out to engage with the flywheel. If the solenoid is bad the starter would still turn but not turn the motor. You would definitely hear that . It has the sound of a pneumatic lug nut driver spinning without being attached to a bolt. If the starter bearing is going bad you can usually figure that out by tapping lightly on the casing of the starter when it is in it's "not start state" and the ignition switch is in start mode. Tapping on the starter jiggles the armature and gives a little air between the armature and commuator. If this makes the starter turn you need to either replace the starter or overhaul it with new brushes and bearing. The starter relay can be checked by verifying you have 12 volts to the small wire during start this voltage engages the relay and enables the two large post on top to short and provide high current to the starter. There is usually 3 or 4 wires to the relay. One is ground, small wire ( or the case of the relay provides this through contact with the mounting bolt ). Second small wire is start voltage from ignition switch through column park switch ( or clutch switch) and brake on position switch. The final two connections are both large cables one goes to the battery and the other goes to your starter. If your ignition switch is in the on position you can short across these two contacts and start your motor when the relay is bad. You have to have a heavy cable or short it with a screwdriver. It will definitely make sparks. Starter relays often go bad due to the heavy load being placed on the internal contacts (50 amps or more) the internal arcing creates carbon build up and eventually corrodes the contacts preventing voltage from being passed across the contacts. Some times if someone is holding the start switch on and it isn't starting tap on the starter relay and see if this makes the starter turn if so you know you need a new relay. Sorry for the drawn out explanations. Hope it helps troubleshoot your problem.

subford · 10-26-2015, 04:36 PM

The starter relay does not handle 50 amps or more. There is only a 12GA wire going from the starter relay to the starter solenoid.
Also the starter will not spin if the starter solenoid does not pull in as the starter solenoid makes the electrical connection between the battery and the starter.

The above information applies to a 1980's and older trucks but not for the 1996 F53.

Here is how the starter relay and solenoid are wired:

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Renenite · 10-27-2015, 06:15 AM

Monday, I was checking the location of the controls, I had to turn the tires to see the starter, I tried starting the RV & the battery was almost dead? I was testing to see if the converter was working right last week per fleetwood it was plugged in, charge increased good. Anyways, I didn't open the disconnects on the batteries & unplugged it & the battery was dead, why? This is the main problem that's been plaguing me for the last 3 yrs, so I plugged it back in to see if the batteries will charge. But this is my main problem, why is the eng battery losing its charge when nothing is on, I'm thinking there's a short some where in the relay or solenoid??? If I open the disconnects then close them before starting it usually will start everytime, I not sure what to check, can you help???

subford · 10-27-2015, 06:38 AM

I am not sure if your converter charges the chassis battery or not.

My converter does not charge the chassis battery. It only charges the coach battery(s) and provide 12 VDC power to the coach while plugged in.

Note that there maybe power to the PCM Computer pin #1 with the disconnects open and if so the battery will be down in about two weeks if not ran as noted by the Ford Motor Co.

This diagram below may be how yours is wired.

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2000 Damon · 10-27-2015, 01:16 PM

Yooo Subford The 12 ga wire you refer to is the wire that energizes the coil of the starter relay which I referred to as a small wire. This wire does not pass the heavy current that goes to the starter. According to your drawing this wire on the drawn vehicle is a size 6 some are size 4 ( the same size as battery cables) . My diesel truck with two batteries has a size 4 cable. I guess if the motor is small enough you could get by with a smaller wire and relay. Your drawing does not show the size of the output wire between the starter relay and the starter. But one could assume since the input wire to the relay contact is a size 6 then the out put contact should be the same. I might be old school but the starters I overhauled during my day had a solenoid attached to the starter which moved the starter bendex gear forward on a shaft into position to engage with the flywheel. The starter did not depend on this unit for its crank voltage. Both units were connected to the positive output (6 ga wire ) from the starter relay. So if the solenoid on the starter went bad and did not move the gear, the starter would still spin with a totally different sound because the gear did not engage with the flywheel.. Now some people confuse the term solenoid and relay. A relay is a solenoid that moves switching contacts ( so the term switch or relay is given) . A solenoid can move many things ( valves, shafts, locks etc. ) The starter solenoid mounted on the starter moves the gear so the term relay or switch does not apply. It is a solenoid

subford · 10-27-2015, 02:27 PM

Damon,
The 12GA wire I spoke of runs from the starter relay and carries the current to the starter solenoid coils. The high current for the starter goes from the batteries to the starter solenoids contacts on top of the starter and then to the starter windings.
The high current for the starter does NOT go through the starter relay.
The small wire that energizes the coil of the starter relay is 18GA and is wire number 32 in the diagram above.

If you do not understand that drawing here is another wiring diagram for the same circuit in the 1990's F53's that may be little clearer. Maybe I should have post it instead of the one above but it does not show the wire sizes and the detail of the one above.

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Renenite · 10-28-2015, 06:29 AM

All wiring is still factory nothing has been changed, still can't find out why the engine battery drains when it's not plugged in, disconnects are closed, nothing is on & sits???
Why the engine battery?? Something is pulling off that battery. My friend used it in July for a concert, he's a sheriff, it was plugged in he said everything worked good he was there 3 days & when he was leaving he went to start it, nothing, he said he played with the key(ignition) & after a few it started???? This totally frustrating.

subford · 10-28-2015, 06:42 AM

It does not sound like a battery problem.
My guess as noted above is either a bad or out of adjustment Neural Safety Switch. I said above to try and pull up on the shift stalk when it does it to see if it starts then.
If not that I would say a bad Starter Relay in the dog house.

Could also be a bad Ignition Switch but I dough that.