PTS 17.5KW 2700 hrs. After running the genset for roughly 70 hours continuous, plugged into shore power for over a week, then running continuously for about 80 hours I noticed the genset overheating. Then found in the `97 Royale that there was a generator stop switch that killed the genset then in about 30 seconds it started right up.... No manual stop that I can find. It was a several minutes before we could pull off and get in the generator bay. Just kept holding stop button ever time it started. At the generator there was not manual off switch, only the 3-way momentary stop/preheat & start positions. I finally just hit all the DC disconnects on the coach and disconnected the the generator battery - success. During all of this I immediately noticed no hot air blowing on my feet from genset cooling fans. Also there was now a bigger than pin-hole in mu lower radiator hose about 4-6 inches from the gen.... I opened the control box and noticed the, what look like 27yo factory, 16/3 SO cord was gummy and melting - but only the green & white - the black hots (2 circuits) were hot but not disintegrating. Our guardian angel must have been watching as we contacted Prevost PASS for assistance and were offered to go to Prevost Ft Worth to plug in, troubleshoot and repair for as long as we needed - now the angel part, where we pulled off was only 2.4 miles from Prevost. So after spraying the bulk of the coolant into the bay we closed everything and headed to Prevost. I didn't do too much investigating as Prevost provided me with a service company for Kubota Generators. I called them in the morning, tech was there about 12:30p and the games began. I'll sum up the experience by saying I told the tech/company to jump in the lake and I did the repairs myself. The tech did dive into the generator while I was running to multiple stores around DFW rounding up parts because the tech had no parts, filters, etc. on him after I had to fill out a detailed spreadsheet questionnaire at 8:15am and provide a CC authorization before they would dispatch. During this time he said the water pump was failing - I spun the pump and he was correct.
So what was wrong? I think a domino effect. Fan wires melted/shorted (but 20A breaker never tripped....). Temps hit 240 indicated and old hose blew. No problem. Replaced 16/3 SO with 10/3 and crimp splices vs wire nuts. Added manual kill switch on side of gen control box (in same path shown on PTS manual schematic). Replaced water pump. Belt looked great, but I have an extra. Replaced failed hoses, the long ones - however I will be doing this again in the near future at I could only find 1.25" radiator/heater hose at Napa, not the reinforced with anti-kink wire stuff it had like they use on boats. None the less it lays in there fine, although it is now a multi stage process to push the genset back into the compartment to not kink or have hose laying on a chafing surface - not ideal but will last the summer. Crawling in the generator bay in 105 deg heat...not fun. Did a full service with filters and a conversion to Delvac1 from Shell T4. Took several times to bring to temp, let sit, etc., to bleed air from system via vent on T-stat housing. Ran great for a few hours, even inside the bay. Then while on the road I turned on the water heater and all was well for about 1 hour - then overheating again. No breakers popped. I ran in and bought an amp clamp multi-meter because I thought the 20A breaker was bad. Well it wasn't, there is a time delay module in the control box that, with the transfer switch transfers load after about 20 seconds or so. I had good voltages, fans were running, etc... Off we went again. About an hour down the road, here we go again. Temps climbing, and I noticed that the AC units shut off and show an E7 alarm on the Dometic t-stat. This time I say the white 4A field breaker popped out (it has never been popped out before). Manual has faulty field breaker several times in the troubleshooting flow charts. I figure, they are thermal breakers, it's hot in there, over 27 years... Ok, bad breaker is possible. So I put the amp clamp on, 1A, all 3 roof airs pop on ~2.8A, turn on the water heater ~3.35A, turn on the microwave and I watched it climb to 4.4A then the breaker popped. So why is my field wire from the main AC output breaker to the voltage regulator so high? SO I reset the breaker and said, it shouldn't be this high but let's just not run the water heater and MW (the MW was really for a load test). Then the AC units started shutting off (E7 error) which used to mean the 4A field breaker was tripped. Well not this time. And in the time it took me to go from the driver seat to the gen bay, the load had transferred and the AC were running again. They held for several minutes in the several of the same cycles to the point of only holding for about 20-30 seconds - all the time with no tripped field breaker. In fact the field wire never gets over 2.8A until it shuts off, it sits at 1A until load is transferred back.
My guess is the voltage regulator has completely failed (it’s on the exciter side now?) – thoughts? The manual is giving me just enough info to be frustrating. Maybe there’s something I’m not seeing.
On a side note, I removed the squirl cage blowing into the generator end to get my fat self into the luxury accommodations of an antifreeze soaked gen bay. I noticed the grate was almost fully obstructed with road dirt/grime similar to fan belt dust, but a bit slimy. I’d like to squirt some engine degreaser in the re and spray it out with a hose. I thought about taking the entire end cap off but didn’t want to wind up pulling the generator apart. Curious on thought’s, etc.. My only concern is the degreaser hitting a conventional bearing and removing all the grease from it, yet I’m certain they are sealed bearings, but yet I ask for thoughts.
Last edited by No Name; 07-12-2024 at 02:57 AM.
Eddie
1997 XL45 Royale
2018 Jeep Wrangler
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Originally Posted by Pipeliner Prevost
