New Again

[DAVEHOLMAN]

I've been a member since I bought a 1984 Carpenter, 4 years ago. I finished that project, took 2 trips, then donated it to a church that lost their bus in Hurricane Harvey.

I got the bug, again. And this time, I know what I did wrong last time. So, I can either make new mistakes, or get some advice BEFORE I buy the next one. lol

I am looking at a 2009 El Dorado EZ Rider II with a Cummins ISL9 CNG engine mated to an Allison B300R.

CONS: The rated "service life" is 12yrs/500,000 miles. This is a rental car shuttle, with only 270,000 miles, not a city bus with a million. I assume the 12 years is mostly because the CNG tanks, which have 3 or 8 years left on them, depending who you ask. So, the drive train should be good for a long time, with low service requirements, and the tank replacement will be a bunch, but not for a few years.
Also, water/waste tanks are problematic, but I think I can get creative there.
Finally, the range is only 450ish miles, and in some places CNG stations are still 500 miles away. But most of my trips are West Coast, and we have them everywhere out here. I've checked between here (SoCal) and Washington, and here to Utah...those are doable. If I decide to do a cross country, it would require some serious planning.

PROS: ALL THAT ROOM! I travel with my brother who is in a wheelchair, 3 grown kids, and often several of their friends. At 35 feet, and wider than a school bus, there are a lot of options to put in a bathroom, bunkhouse, entertainment center, etc. And it has not one, but 2 wheelchair ramps, so like, putting a table across the aisle up front wouldn't have to be undone every time we get in or out.
Like I said, the powertrain is inexpensive (relatively) to operate and maintain.

I mostly do multi day road trips with a motel stay at the destination, so I don't have huge water/120v needs. An extra guest battery or two, and a medium sized inverter, along with 50 gals of water and similar waste tanks should be adequate.

So...what am I missing?

 

[Truthseeker4449]

What sort of route was this shuttle running? It may not have ever been loaded heavy, but if the route never was over 25 mph or less than a few miles in length it might be just as worn out. Check for blowby, the lack of any will suggest a healthy engine. Get the engine hours and convert the hours into mileage.

Definitely double check those tanks, get up on the roof and open up those access panels. They will be marked with a discard year, the lifespan of the tanks will dictate how long the bus is really good for.

Those engines do require a special oil that is not available at most auto parts stores. This is because CNG buses produce a lot of water as part of the combustion process and a good amount of it ends up in the oil. The normal additive package in diesel oil for keeping the soot in suspension does not mix well with the water.

The ISL-Gs tend to suffer from ignition related misfires a lot. Ignition harness failures are not rare and there is an updated harness available now that includes extra ground wires. Coil boots must be changed with the plugs to help keep problems at bay.

Also for a while these engines were prone to melting pistons. Again there's a fix for this, but still requires an engine teardown to install new pistons and liners.

Do not store these buses inside and be wary of lighting open flames in them or near them. The CNG systems do tend to leak down. I highly recommend closing the CNG shut off valve whenever you park to avoid losing the entire fuel load.

I've been working on a lot of NABI buses as of late with the same engine, I'm not an expert on these engines yet, but I'm now more experienced with them than anyone else in my shop. That's not saying a whole lot, aside from many shops don't really know how to handle a CNG bus if one were to come in.

You should read up more on operating manuals and practices if you decide to move forward. Aside from that it sounds interesting and honestly I've kinda pondered one myself.

 

[DAVEHOLMAN]

Thanks! I'm going to look at it/drive it Friday. I'll definitely check the tanks. I take it the tanks start leaking over time, kind of regardless of how they're used? As in, doesn't matter where they are weather-wise, or how often they're filled, etc?

As far as the route...its an off-site rental yard by LAX, and about 2 miles each way is freeway, so they must get up to 45-50 mph some of the way. But, yeah...a lot of stop and go/idling in the airport itself.

 

[Truthseeker4449]

Thanks! I'm going to look at it/drive it Friday. I'll definitely check the tanks. I take it the tanks start leaking over time, kind of regardless of how they're used? As in, doesn't matter where they are weather-wise, or how often they're filled, etc?

As far as the route...its an off-site rental yard by LAX, and about 2 miles each way is freeway, so they must get up to 45-50 mph some of the way. But, yeah...a lot of stop and go/idling in the airport itself.

Might be alright then as far overall wear, still try and get engine hours.

I believe the main source of the leaks are downstream of the shut off valve, where they are a number of connection points and sensors, plus the engines own shut down valve, pressure gauges, and the fuel regulators.

At least on the buses I've been working on, after I close the shut off valve, the pressure is usually gone in anywhere from a few hours to a few days. Perhaps this is not supposed to be happening, but the fleet I've been fixing up is in such a sorry state that if I don't smell gas, then it's not significant enough to worry about.