1986 350 need help to figure out

[Graymac]

Good afternoon.
I have 1980 motor home with a 350 engine and according to the serial number was built 1986 or newer.

Problem I am having is a total lack of power under load, spews black soot on startup.

Hasn't ran much this past two years but was starting to act up before parking it.

Today I pulled the housing off to have a look and see.
Found one plug wire completely off, checked the plugs and everyone was only hand tight.
Pulled them all and cleaned up and re gapped to 0.40

Starts better, but now idles quite high and still stalls out under load.

Any thoughts on where to start?

Rochester quadrant carb
Thanks in advance as I am sure it is an easy questions for some.
Brian

 

[txab]

I'd probably look at rebuilding that Quadra Jet for starters. Ethanol fuel doesn't play well with fuel systems when it is just sitting around and getting old. But sounds like you need a carb adjustment including the choke. Also check for vacuum leaks. Check timing too. That's a few things to consider

 

[OldCracker29]

The fuel filter on those quadropukes gum up and need cleaned often. I'd start with the carb and then do a complete tuneup on it along with an oil change after you get it running good.

 

[Graymac]

Thanks guys. I guessed that's where I should start, but it is always nice to have confirmation.
Brian

 

[PenguinLTZ]

When all that is done, check for vacuum leaks. Manifold, etc. you mentioned a high idle

 

[Graymac]

Yea it started idling high after I cleaned and gapped plugs. Changed fuel filter and pinched fuel line. Still idles high and as soon as i put it in gear it dies.
Frustrating as I am selling it but don't want to sell a lemon.

 

[OldCracker29]

Yea it started idling high after I cleaned and gapped plugs. Changed fuel filter and pinched fuel line. Still idles high and as soon as i put it in gear it dies.
Frustrating as I am selling it but don't want to sell a lemon.

I would rebuild the carburetor.