Stalling

[divemedic]

so my wife has been driving the 77 while the windshield is getting repaired on our other truck. She's complained of intermittent engine shut downs. She's finally been able to assess symptoms and I was able to follow her today as we left home.

- Black smoke during acceleration/ throttle increase

- rapid drop in rpm

- no changes to oil pressure gauge

She states she can recover the engine speed with rapid gas pedal feathers. If the engine does shut down, she's only ever able to start it with throttle feather.

Historically, the truck starts easily and without hesitation. No loss of power noted. Did not smoke at all.

I'm inclined to investigate the fueling side of business. Any advice?

 

[GreaseMonkeyJP]

I would be on the lookout for a leak in the fuel system allowing air in.

When my fuel primer pump went it let so much air in that it stalled, and I had a similar experience of needing some throttle to restart.

I also recently had an issue where I would loose power during driving at the same point in my commute every morning and found that it was just the fuel filter being loose, and the seal would break and let in air when I took a tight right hand turn.

 

[divemedic]

Awesome thank you!

 

[Tennessee Jed]

Nic did you ever figure this out? Just curious.

 

[divemedic]

I haven't yet. Unfortunately I've been busy with a home reno project which is keeping me busy.

 

[roscoFJ73]

I would drive until it begins to stumble, then give it a few pumps with the hand pump on the fuel filter.. I have had 2 1HZs get air into the pump from where the rubber fuel line joins the metal fuel line near the injection pump. I forget if its the inlet or outlet that goes back to the tank.

 

[joekatana]

Probably air getting in the fuel lines, try to pump it up before you start it, it should hold its pressure so if you can pump it several times you can start chasing the culprit.

 

[ALEXY]

I have a piece of transparent hose between fuel filter and pump. That is easiest way to tell if air is likely the problem.

 

[divemedic]

Funny thing is, I drive around trying to reproduce the issue and I can't. It's never stalled on me. Once I get my garage cleaned out I'll be doing quite a few things to the 70 over winter. Maybe I can nail down the issue then.