[Dustywrenches]

Hello, I am brand new to this forum and helping a friend out with his 85 350 4WD pick up. It only has 68,000 miles on it and has been sitting for 10 years or so. The engine backfires through the carb when we try to start it and sometimes throws a good size fireball up too! It has the 4bbl Ford/Holley double bowl carb which I rebuilt. Also I can't get the choke to operate consistently so I have to hold the choke closed to start it again even if it is still warm. I checked the timing with the vacuum hose disconnected and the mark jumps around about 20 degrees or so. When I took for a test ride it would stall if I gave it gas too fast and doesn't have much power.

After reading a ton of threads with guys having the same issue I'm thinking this is a common problem maybe??? Has anybody discovered the fix for this problem??

Thanks in advance for ANY help and suggestions!

 

[pedal2themetal45]

HI,
The timing mark jumping around is a classic sign that the timing chain is bad and in need of replacement along with the timing gears.. thats the cause of the back firing. The timing mark should be solid at idle..

good luck take care be safe
tim

 

[427HISS]

Yep, that's what I was going to say. Take the cover off and see.

 

[Dustywrenches]

HI,
The timing mark jumping around is a classic sign that the timing chain is bad and in need of replacement along with the timing gears.. thats the cause of the back firing. The timing mark should be solid at idle..

good luck take care be safe
tim

Thanks for the answer (Not the one I was hoping for) I had a suspicion that could be it! I heard that you can pop the distributer cap off and crank the engine right and left to see how much play is in it.

 

[pedal2themetal45]

HI,
Yeah you can do that (move it by hand CW and CCW) the rotor should move at the same time as the crank.. but most likely its not going to .. as well as jump time with a lose chain..
It is a little bit of a PITA but it well run better with a new one.. Since its an 85 I'm not sure you can use a straight up (0*) set.. with it being somewhat computer controlled.. MadPorter well know it he replies or John.

good luck take care be safe
tim