Starting problem

[starduster]

I have a cat 300hp that just had a starter literally burn out. (It looked like a welding fire) the casting at the end cap of the solenoid on the starter partially melted. I replaced the starter and the key will turn on the starting circuit (Lights up the dash indicators etc) but will not actually make the starting motor turn the engine over when turned to the starter position. I found a relay in the engine compartment mounted on the frame rail that has one very small red wire and two medium size wires lugged to it. If I jump across the two large lugs with an insulated screw driver with the ignition key in the normal "on" running position the starter will turn and start the engine. I am trying to figure out if that relay with the lugs on it is bad or if I have a bad ignition switch? Is there anything else in the starting circuit that could cause this? I did also probe from the hot in the back of the ignition switch to each of the other wires coming out of that switch but was not able to make the starter turn.

[starduster]

I have a cat 300hp that just had a starter literally burn out. (It looked like a welding fire) the casting at the end cap of the solenoid on the starter partially melted. I replaced the starter and the key will turn on the starting circuit (Lights up the dash indicators etc) but will not actually make the starting motor turn the engine over when turned to the starter position. I found a relay in the engine compartment mounted on the frame rail that has one very small red wire and two medium size wires lugged to it. If I jump across the two large lugs with an insulated screw driver with the ignition key in the normal "on" running position the starter will turn and start the engine. I am trying to figure out if that relay with the lugs on it is bad or if I have a bad ignition switch? Is there anything else in the starting circuit that could cause this? I did also probe from the hot in the back of the ignition switch to each of the other wires coming out of that switch but was not able to make the starter turn.

[Ragman]

Hi Starduster, Welcome to the iRV2 Forum.

Last fall we purchased a 2001 National Tradewinds with a 330 CAT. Took a 1000 mile shakedown cruise; then we headed for Mazatlan, Mex. We stopped in NM to fill up with propane and had the same problem with the relay that you described. Jump-started with a screwdriver, continued to Mazatlan with no problem. It started every time.

We arrived at our campground in Mazatlan, pulled into our space and she was "dead in the water." Like you, I wondered if it was the ignition switch or what? While checking the relay, one of the larger cables was hot. I pulled off the small wire and using a 12-V light probe, had my wife turn ignition on and found the wire it was hot. I felt this eliminated any problem with the ignition. So I decided it must be the relay. I located an Auto Zone and after five tries and the guy going up and down the ladder looking for one, he found one exactly like mine. Cost: $22 American dollars. Yeah!! Went back to campground, slapped it on and it has worked ever since.

Test that small wire and ask your DW to turn on the ignition. (We used our 2-way radios to communicate)If it's hot I'll bet the relay is your problem. I would also check the other cable to make sure it isn't hot with the ignition on. I hope this helps you.


IRV 2 has been a great help to me in maintaining our motor homes over the past six years. I hope you enjoy it as well.

P.S. You may not know it, but you've already taught me something.... I've been calling that blasted relay a solenoid all the time. Never get too old to learn.
Larry

[starduster]

Actually you taught me two things, The device I was calling a relay is actually a solenoid. I assumed it was not a solenoid because the person who sold me the starter motor told me that the starter solenoid was built in. If it is then I have a two solenoid starting circuit. I did find the part at Autozone (ford part)today and when installed my key now starts my motohome once again. Thanks for confirming my suspicion.

[RLS]

I had the same problem on my coach. I cleaned all the battery connections and all the leads going to the starter. That didn't help. I replaced the solonoid that your talking about, problem solved. Cost was just over $17.00 at the local Freightliner parts house. If you need the part number let me know and I will look it up for you.
Bob

[starduster]

Thank you for sharing your experience with this problem. Your input lead me to purchase a Ford solenoid for around $17.50 at a local auto parts store and that solved the problem.