Battling running issues since Labor Day 2023

[byekryam]

I apologize for the long post ahead of time.....

Still battling getting this RV back road worthy since Labor Day 2023 when we broke down in Delaware (no electrical to engine)

Multiple mechanics, some said they could do it and then decided they couldn't, some started to work on it then months later weren't doing anything so I had to bring it somewhere else, others did some repairs, multiple tows, finally towed to mechanic in Maryland, supposedly fixed, spent $6,200.00 in mechanic fees combined with towing fees between everyone (1st mechanic fixed a ground issue\2nd mechanic replaced diode on old distributor and changed thermostat)

I went down to pick up RV in May 2024, got 2 miles from mechanic and it started bucking. Would drive fine up to about 25 mph and then would try to stall when strain was put on engine. I couldn't afford any more mechanic fees or towing so I drove it home from Maryland between 25 mph – 40 mph bucking the whole way pumping the pedal constantly so as not to stall

Since getting it home I have:

Removed, dipped, and rebuilt carburetor, and reinstalled

Replaced distributor

Replaced mechanical fuel pump on engine

Replaced spark plugs

Replaced air cleaner

Removed, cleaned, and re-set spark arrestor air cleaner shield

Replaced as much of emissions valves as possible (PVC, EGR, etc. - some not made anymore)

Replaced as much of vacuum hosing as accessible

Blew out as much of the fuel lines and hoses as accessible

Replaced some of the fuel hoses as accessible

Replaced inline fuel filter

Replaced the inline fuel pressure regulator (just to rear of back tires on passenger side in frame)

Replaced the tank selector switch by back fuel tanks

Added 3 grounds to frame, body, engine, and dash frame

At present I can't get fuel from back tanks to engine. The new fuel selector switch shows it is reading both tanks as when I switch from front tank to back tank it shows changes in fuel levels so I believe that is working properly

I have driven it up to 50 mph on the highway by using a portable gas tank to the mechanical pump on the engine without any further bucking\stalling.

I have an inline electric fuel pump I was going to install, but haven't gotten to that yet, to help prime the engine to help start easier

Right now it's at a mechanic by me who has a lift that can pick it up so I can drop the tanks and change out the fuel pumps in each tank and change any last fuel lines. It's been there a week and I called for an update today because we're supposed to go away this weekend and not cancel our 2nd trip this summer but he told me there's no electrical to the fuel tanks (even though when I switch the tank sensor switch back and forth, the fuel gauge changes accordingly) and he doesn't want to get involved (thanks for the heads up earlier - needless to say trip #2 canceled). He says he can't find a wiring diagram for the P30 Winnebago fuel wiring. I looked through all my manuals and I have plenty of Chevy P30 diagrams, but none specific to the Winnebago showing the fuel electrical diagrams. Does anyone have this specific diagram (1986 Chieftain 31)? I can't find it online. Thanks

[Eyez Open]

https://www.classicwinnebagos.com/forum/index.php?topic=8795.0

For Reference:
You do realize that all this information is from the free book (Member Area, Manuals, Diagrams & Tech Info, scroll down to chassis section and select Chevy/GM P-30 Service and Maintenance Manual).   Both I and the Barth write up are referrencing pages in that book.