Pressure runs too low on MCI-5C

[luvrbus]

Different PPV valves have different pop pressure they are not all the same

[chuckdrum]

Hey Gents,

Sorry I abandoned you on this thread...

I decided there were enough different possible problems here that I should take it in to someone who knows these systems well.  All indications were that the governor was bad, but a trained eye might discover other items, as well.

I checked with some of the shops I've used in the past for specific issues, and none were interested in helping me. Mostly, they appear to be abandoning RVs of any kind. Then I got a lead from NW Bus Sales (where my coach was purchased back in the mid 90's by the guy who did the build out)-- GLM Charters in Puyallup WA.  They run a handful of bus charters but also have their own shop and work on other rigs, as well.  Can't believe it's taken me 8 years to find this guy but I'm sure glad I did.  Gary is definitely my new best bud, as he's familiar with older MCI and Prevost coaches as well as some of the newer models.

Anyway, he ended up replacing the governor and everything works great now.  Cuts out around 125psi, back in around 90.  He said compressor and air dryer were fine.  He drained all the tanks and found no water, so the air dryer (not original equipment) is working well. 

He also replaced my main fan belt, as I was having difficulty removing the bumper that would give access to that. 

With help from all of you, the research I did on my own, and my new mechanic, I've learned quite a lot about air systems in the past couple weeks!  Thanks for your assistance and expertise.

Once I get my Webasto back together (took it to my local dealer to verify that the controller had to be replaced), I'll be ready to hit the road again!  And stop if I have to!

Peace,

Chuck

[luvrbus]

The 25 to 30 lb drop is one thing I never like about about D style governor ,I installed the 0-1 type on my coach you adjust with shims now I just have a 5 lb drop between the ranges 

[richard5933]

Good news. Glad you found the problem and that it was something simple. Also glad that you now have a resource in your area with this mechanic.