Leveling switch question

[Prevost.Rick]

graig call me mon your country has a secondary leveling system i,ll update you on c/c and prevost systems 813-833-2284 rick thank you

[craiglenz]

Well guys i moved the coach today after sitting for three days. Air held good and no leans. Before I left I tried exhausting the air and all worked well with the leveling system. All three points raised and lowered as they should. When I arrived at my next stop and went to level the coach same thing. Little pssts of air when i tried to lower any of the points. After chasing around the switches as before it started to work again. So it seems it is when the coach comes out of ROAD position that this problem occurs. Sorry Rick havent been able to get a chance to call but will make a point to tomorrow. If this spurs any ideas Im all ears.

On a side note I just had my inverters removed and serviced in Richmond California. They were new in 2005 and used very little. The inverters would go into overtemp when charging. Turns out BOTH had fan failures. Strikes me as strange they would both go out at the same time but they were both dead. Ernie the service tech there put them on his scopes and load tested them and all was fine. Put new fans in and were back in business. Have no idea how long they were out. Batteries were dead when i did my pre buy inspection and now with new batteries in the coach the overtemp issue came to light. Good to know now that the battery bay has been fully serviced. Couldnt be more happy with the service Ernie at Xantrex gave me. Highly recommend him to the group.

[tpr]

Craig,

I have had two Angola Coaches before my present coach. A 1991 MCI and a 1996 Prevost. The 96 had chronic air problems, prevost told me the air system was contaminated with moisture and gunk from the Jun Air aux compressor. They told me the aux aircompressor was tapped into the system after the air dryer(I don't know how true that was). The gunk would make the cylinders in the norgren valves either stick or move slowly to fill or exhaust air. After chasing leaks and stuck valves for a few years I had Prevost purge and clean out the air system and replace the norgrens. It helped alot, the only one that ever needed attention after that was the 5 way in the compartment under the drivers area. I always carried a few spare norgren valves just in case as any mechanic can change them. Angola made fine coaches and after you de -bug it you should have a comfortable and reliable ride.

[craiglenz]

This morning "The Bus Depot" in Las Vegas took a look at my leveling problem and ended up replacing one of the Valve Spools. Part # 641927. First they took apart the five valve norgren valve and inspected and cleaned it but all was good. Seemed to be a little unfamiliar with the 5 valve vs 4valve norgren which they run on the majority of the fleet coaches they service. One point I thought Id mention is now when the selector switch on the leveling system is moved from the drive position to the left, right or front positions it gives off a short exhaust of air. Didnt do that when it was giving me trouble. Since the coach is new to me I didnt pick up on it cause I didnt know that it should do that. Now its quite obvious. The learning continues but now the bus levels as it should. And for an added bonus it seems to hold it there.

Thanks guys for the input on this. If ever in Las Vegas John over at "The Bus Depot" on South Decatur Boulevard has a real nice four bay shop with full length pits on two, coach lift and a full service spot free wash as well. Highly recommend their service.

Merry Christmas Poggers,

Craig

[Jon Wehrenberg]

Craig,

One of the hardest parts of ownership is sometimes we do not have a benchmark for determining the difference between what is the correct operating condition, or an abnormal one. Anyone new to a Prevost might not recognize a problem with shifting, or Jake brake operation or suspension control operation. With respect to the suspension not all systems function the same because over the years Prevost made changes to the design and operating logic, and converters sometimes altered the system to provide some features. So in the case of the suspension even experienced owners changing converters may not be sure what is correct or a sign of a defect.

I don't have and have never had a pure Prevost level low system so for me to know if a short whiff of air is normal. Few of us can know every single variation and how each performs.

While I kid about us sometimes giving correct answers, it is the truth. We can only speculate sometimes.

Diagnosing any of the suspension systems often requires a hands on approach and a meticulous step by step verification each component is functioning as required, starting with the electrical side of the system and then following the pneumatics. It sounds daunting, but if someone undertands the system well enough it is actually very easy to follow through the system(s) and isolate the bad part or parts. And it can be done quickly. I did a diagnosis on a bus and in less time than it took to remove the bad valve I was able to zero in on the culprit, and taking it apart proved it was in fact what was wrong.

Diagnosing on a forum is also difficult because having eyes, ears and fingers on the bus is significantly better than trying to interpret the written word.

Glad you have it resolved. We have far too often felt the pain of a POG member who had his wallet vacuumed by service techs who were getting on the job training.

[craiglenz]

Thanks Jon and everyone who help us newbies learn our coaches. That's is absolutely true that with something new "to us", one doesn't have the ability to diagnose a problem based on "how it operated when it was working correctly" as was the case with this leveling system. One always questions if its the system that's not working right or if I simply don't know what "it should" work like. Fortunately for a coach that has such low miles for being 15 years old it seems that things are coming together and the butterflies are getting fewer and fewer with each new sound I awake to. :-)

Thanks again, Merry Christmas and a Happy New Year to all of you.