Bus Breakdown 8v92

[Loc]

On Saturday we headed out for a short one-night camping trip. When we arrived at the campground about 90 miles northwest of Houston I stopped to register (nice Corps of Engineers' Park on Lake Somerville). When I got back in the bus it would turnover but not start. It seemed like the engine wasn't getting any fuel. I checked the fuel filter to make sure that it was indeed getting fuel - it was. I tried to start the coach from the rear, again it would crank but not fire. This is a 1992 Angola Conversion with an 8v92 with DDEC II (258K miles with about 50K on a full rebuild) and an HT 755 ATEC Allison.

With a little more trouble shooting, I noticed that when I turned the ignition key on that the CEL and SEL (Check Engine Light and Stop Engine Light) did not illuminate as normal when the key is turned to the on/run position (normally the CEL and SEL illuminiate for about three seconds and then go off). Howerver, the CTL (Check Tranmission Light) did illuminate with the key in the on postion which is not normal. I tried checking codes on the ATEC and DDEC but with no luck - no flashing lights on the dash board. I got on the phone to DFW Prevost to ask for some assitance. They walked me through a number of things over the next hour and a half to see if we could find the problem. I and they believed that it had something to do with the DDEC or ATEC. We checked power to breakers front and rear, power to relays and whether the relays were working. Everything checked out normal. They went to the shop to look at the wiring diagram and we did a little more troubleshooting until they finally said that it was likely the ECM.

To make a short story long, I finally called Coach-Net to ask for towing assitance since it appeared we weren't going to be driving the bus anywhere. Coach-Net (as usual) was very responsive and there was a tow truck at our aid within a couple of hours. By this time is was dark and they did not want to tow the bus at night. The driver took my keys and they towed the bus back to Houston on Sunday.

The bus is at Stewart and Stevenson and they have started work on it. I will let you know what they find. In the meantime, anyone on the board have any thoughts?

[grross]

Did you check the Allision transmission fuses that are located near the steering box in a non-descript 4X4 plastic box? Similar problem happened to me a year ago with our 99 Marathon. It only took 12 hours to find the box with the assistance of Marathon, Alison and Prevost!!!
Good Luck

[Loc]

Yes if it is the same box. I spent some time finding the box and then walked through checking it with Prevost on the phone.

[Ray Davis]

I had a problem attempting to leave Kerrville last October, after sitting for 8 days. Similar, but it sounds different. But, I'll mention it, just in case.

My coach wouldn't start, but in that case the check engine and stop engine light were lit. It turns out that I was low on coolant, which prevented the engine from running. At the time I didn't have a jumper to try to blink the error codes, nor did I have a Pro Driver to tell me.

Adding coolant solved the problem, and I was on the way.

Best of luck ....

[Jerry Winchester]

LOC,

As we have the same vintage coach / engine I would have gladly seined up the DDEC code reader and motored over to the lake to help you out. I would think you might have a sensor problem that is keeping the DDEC computer from telling the injectors to do their thing. Unless it was smoking when you tried to start it.

And not to fault your process, but having had several large vehicles not restart in a similar fashion leaving me blocking a road or in a bad spot, so I rarely shut the engine down when fueling, checking in at the RV park or any other intermediate step between leaving the hanger and parking for the night.

I will be curious to learn how your trip to Stewart & Stevenson goes. At their admission they only have a few 8V92 guys left in the shop and I would like to know how they do.

[JIM CHALOUPKA]

Jerry, Thanks for your tip on the Do Not Shut Down Until You Are Destinated. I will try to remember that.
JIM

[Loc]

Jerry,

I think an investment in a DDEC reader might be worthwile for my vintage coach. Where did you purchase yours and what was the approximate cost (if you don't mind saying). If I had one, I could have more quickly diagnosed that I needed a tow truck or even perhaps found and fixed the issue (fixed may be optimistic). Are you willing to offer remedial DDEC reader operating classes? I am assuming that the reader plugs into the port in the lower compartment below the driver's seat and is realtively easy to use.

On the other point - I agree. I usually let her run when fueling or checking in, but for whatever reason I decided to shut her down on Saturday. Thankfully, I pulled into a parking space and was not blocking anything. Had I been blocking the road that would have probably resulted in a divorce given my gleeful attitutde at the time.

I have had the bus at S&S (Houston) at least ten times in the last five years. They have replaced injectors, a transmission sensor, a couple of engine sensors, the engine compartment oil pressure guage and run the rack, etc. S&S in Albuquerque did my engine rebuild. Sometimes it takes a couple of days to get in to the shop given the availability of their 8V mechanics. So far they have done a pretty good job. Do you have a good 8V mechanic?

Loc

[truk4u]

Loc,

Are you coming to POG 3? JDUB checked out a bunch of Coaches at POG 2 with his reader.

[Jerry Winchester]

LOC,

I bought the DDEC reader on eBay. There are usually a couple of them for sale each month and they range from $500 to $700 depending on the modules you get, if it has the printer, etc. You can also pick up the DDEC Troubleshooting manual there as they come along pretty often.

Funny thing, when we hooked up the reader to A$$Crak4U's coach, it said there was a loose nut behind the wheel and something about too much Viagra. What's up with that?

No, the only 8V mechanic I have laying around is my dad. He rebuilt and tuned 8V's for 25 years, but retired about the time the DDEC stuff hit Detriot Diesel. He is, for some strange reason, very competant on CAT engines with electronic controls. Go figure.

JDUB

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[Loc]

Tom

I am going to try to attend. I have a trip to Asia that I am trying to reschedule, but it isn't looking good.

Jerry,

Since my attendance at POGIII is not looking likely, may I impose (with a proper offering/sacrifice) to find a time that is convenient for you to bring the bus up to Cypress and get an up close and personal look at the DDEC reader in action?

Loc