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How to Fix Onan Cummins HGJBB 2.8 Generator Carburetor Problems After
Engine Hard 2-4 hours 84 👍

How to Fix Onan Cummins HGJBB 2.8 Generator Carburetor Problems After

Called the landlord about the Onan Cummins HGJBB 2.8 generator in my rental RV and he just said "figure it out" when the carburetor started acting up after winter. Left our 2017 Winnebago Travato 59K with its Onan Cummins HGJBB 2.8 generator sitting for almost a year (oops), and now it's throwing a tantrum. It's running rougher than a shopping cart with a wonky wheel, and the moment I try to put any load on it - like actually using it for something useful - it just gives up and dies on me.

I removed the carburetor, and my friend helped me clean it in a sonic cleaner. Now I'm stuck because I'm not sure if the throttle and choke linkage are correctly positioned when I reinstalled it. I've confirmed fuel is getting to the carburetor, but it won't start. I took some pictures showing the wire connections and mounting, hoping someone can help me figure out the precise linkage setup.

I'm pretty sure I know what's wrong (thanks, old gas and my laziness with fuel stabilizer), but I'm wondering if anyone can confirm my suspicions about what happens to these carburetors when they sit with stale fuel. Is this the classic 'your carburetor is now a museum of varnish' situation? And if so, what's the real deal on getting it cleaned up and running again? …more
DPF Failure Code: Repair Cost & DIY Options for RV Diesel
Engine Medium 4-6 hours research and shop visits 82 👍

DPF Failure Code: Repair Cost & DIY Options for RV Diesel

According to my diagnostic scan the DPF failure code shouldn't be appearing since regeneration happened just 500 miles ago on my 2022 Holiday Rambler Cummins B6.7. Local Freightliner service center is quoting $6,400 for complete DPF replacement at 38,000 miles.

Before proceeding with this expensive repair, I need to verify: Is this quote within normal range for dealer pricing? Should my 2022 engine still have emissions warranty coverage that would apply to DPF failure? Are there alternative repair options like professional cleaning that might resolve the issue without full replacement?

Looking for technical guidance on the most cost-effective approach to address this DPF failure code before committing to the quoted repair. …more
Onan 7500 QD Code 36 Fix: How to Solve Generator Overfill Oil Shutdown Problems
Engine Easy 45 minutes 82 👍

Onan 7500 QD Code 36 Fix: How to Solve Generator Overfill Oil Shutdown Problems

Woke up this morning to fire up my Onan 7500KW QD for camping season, and that dreaded Code 36 shutdown nightmare is back again. I can restart it after waiting a bit, but this is driving me nuts.

I've been digging around online and came across something weird - apparently these dipsticks are calibrated wrong? Some folks are saying you're supposed to keep the oil level just above the 'ADD 1QT' mark instead of at the full line to avoid overfill shutdowns. That sounds backwards to me, but I'm seeing it mentioned everywhere.

Before I start messing with oil levels or throwing money at fuel pumps and control boards, can anyone confirm if this dipstick thing is actually legit? Really hoping it's something this simple! …more
Onan Generator Won't Stay Running: Complete Repair vs Replace Guide 20
Engine Medium Decision process 77 👍

Onan Generator Won't Stay Running: Complete Repair vs Replace Guide 20

Three distinct sputtering sounds keep coming from my Onan generator that fires up perfectly but dies out after running for a while. Multiple service calls and repairs have been attempted, but the problems persist intermittently, making diagnosis challenging.

The repair costs are accumulating significantly, and I'm reaching a decision point regarding whether to continue troubleshooting or consider replacement options. What criteria should I use to determine when total repair investment justifies switching to a replacement unit? Are refurbished Onan generators a viable alternative, and what factors should guide this repair-versus-replace analysis for intermittent generator failures?

(Note: This is specifically about my RV's Onan generator, which I'm referring to as my 'Jenny'.) …more
Cummins ISM 500HP at 142K Miles: High Mileage or Just Getting Started?
Engine Medium 2-3 hours inspection 70 👍

Cummins ISM 500HP at 142K Miles: High Mileage or Just Getting Started?

Planning to buy my first diesel pusher and I'm completely clueless whether 142,187 miles on this 2005 Cummins ISM 500HP is considered high mileage. The coach is equipped with a Cummins ISM 500 horsepower engine paired with an Allison MH 4000 6-speed transmission. While I've done some research on these powertrains, I'm getting mixed opinions about what constitutes "high mileage" for this particular combination.

Some people are telling me that anything over 100K miles is getting into risky territory, while others say these commercial-grade engines are just getting broken in at that point. I want to make sure I'm not walking into a money pit, but I also don't want to pass up a good coach if the mileage number is scaring me unnecessarily.

What's the realistic lifespan expectation for the Cummins ISM 500HP and Allison MH4000 combination? Should 142K miles be a red flag that makes me walk away, or is this actually considered moderate mileage for these heavy-duty components? I'm trying to determine if I should focus more on the maintenance history and overall condition rather than getting hung up on the odometer reading. …more
2003 Fleetwood Southwind Exhaust Manifold Repair in Waukesha WI RV Services
Engine Hard 8-16 hours 67 👍

2003 Fleetwood Southwind Exhaust Manifold Repair in Waukesha WI RV Services

The exhaust manifold gasket on my 2003 Fleetwood Southwind is shot and I'm staring at a hefty repair bill — worth fixing or time to walk away? The situation is complicated by four broken studs that are flush with the head, which means this repair will likely require head removal to properly extract the damaged hardware.

Given the complexity of this repair on a motorhome chassis, I need to identify the appropriate type of service facility in the Waukesha, Wisconsin area. This isn't a standard automotive repair - it requires specialized knowledge of RV systems and heavy-duty engine work.

What type of professional service centers should I be targeting for this level of exhaust manifold repair work on my Fleetwood Southwind? …more
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