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‘94 Hard Start (video)

You are on the right track. possibilities:
Sucking air
Fuel drains back to tank
Fuel leak
Lift pump not building pressure (which I never heard the tone of LP change before cranking)

So- I would ask:
what is fuel pressure before and after LP cycles before cranking engine? and while cranking engine?

Set up phone on video if by yourself or have someone crank while you watch the clear return line.
 
Will L. said:
You are on the right track. possibilities:
Sucking air
Fuel drains back to tank
Fuel leak
Lift pump not building pressure (which I never heard the tone of LP change before cranking)

So- I would ask:
what is fuel pressure before and after LP cycles before cranking engine? and while cranking engine?

Set up phone on video if by yourself or have someone crank while you watch the clear return line.
Click to expand...

1) I am in Montana and truck is in California.
2) Brand new Walbro lift pump that I installed.
3) I replaced return line hosing only on driver’s side when I replaced the IP. Told him to inspect those with flashlight while running at night.
 
Walbro FRC-10? They back in stock somewhere?

30 seconds of cranking and then take a 2 min break.

This condition is extremely hard on the starter as you hear it thrown out at high RPM. The overrun clutch in it may be the first part to fail. Powermaster covered it for me...

Till it's "fixed": Have them put their foot on the throttle halfway to the floor or floor it. Lift when it starts to avoid the engine RPM race to the moon. Experience working the throttle will help keeping it from hitting redline.

More throttle helps get the air out of the system.
 
WarWagon said:
Walbro FRC-10? They back in stock somewhere?

30 seconds of cranking and then take a 2 min break.

This condition is extremely hard on the starter as you hear it thrown out at high RPM. The overrun clutch in it may be the first part to fail. Powermaster covered it for me...

Till it's "fixed": Have them put their foot on the throttle halfway to the floor or floor it. Lift when it starts to avoid the engine RPM race to the moon. Experience working the throttle will help keeping it from hitting redline.

More throttle helps get the air out of the system.
Click to expand...

Bought the original Walbro FRC 10 from Leroy. Sat on the shelf until this year when Installed it to absolutely rule out fuel pressure to the IP as an issue. Truck was work fine until. Tuesday of this week.
 
could be a supply line, clamp, or fitting somewhere sucking air. have him get a recording of the clear hose on the IP return while cranking it up to see if there are any air bubbles. the worst is the injector lines bleeding off pressure while sitting. have him inspect all the lines at the injectors for any evidence of leaks or at the IP where the lines connect.
 
dbrannon79 said:
could be a supply line, clamp, or fitting somewhere sucking air. have him get a recording of the clear hose on the IP return while cranking it up to see if there are any air bubbles. the worst is the injector lines bleeding off pressure while sitting. have him inspect all the lines at the injectors for any evidence of leaks or at the IP where the lines connect.
Click to expand...

Those were my instructions last night. I verified no leaks at the IP. I am suspicious of the cap/plug on the last injector on driver's side. I pushed that on with the clamp on it. I tested it several times by pulling hard on it. Still, it was a blind shot on the install and I always suspect.
 
This morning update: Once the truck starts it runs fine, but once it gets under a load like going up a hill, it starts to sputter in the higher RPMs. No obvious diesel coming from any of the injectors on driver's side and the first two on the passenger side. No air bubbles in the clear return line at the IP. Said it stalled twice driving it this am and it took a long time to restart, like it's fuel starvation.

For reference, I installed a filter before the Walbro. He'll go through it over the weekend.
 
You said: “... to absolutely rule out fuel pressure to the IP as an issue...”
Nope. Sorry, it doesn’t work that way. New defective, something like dirt or water gets in there, fuel line or clamp fails, this list could go on an on.

Fuel Pressure Gauge- it HAS TO BE at the ip. You can guess at it all day long or decide to do it how stanandyne said to diagnose it to dealerships.
 
Will L. said:
You said: “... to absolutely rule out fuel pressure to the IP as an issue...”
Nope. Sorry, it doesn’t work that way. New defective, something like dirt or water gets in there, fuel line or clamp fails, this list could go on an on.

Fuel Pressure Gauge- it HAS TO BE at the ip. You can guess at it all day long or decide to do it how stanandyne said to diagnose it to dealerships.
Click to expand...

I told him we need to install the pressure gauge. Need the fitting. It will just be laying in the engine compartment.
 
Wire fall off the lift pump?

Do you still have the screen in the fuel pump? Just be aware if you are looking for plugged screens, filters, tank socks...

frc-10.jpg
 
Colby has been using my Honda and has not had time to work on the ‘94 Suburban. He had to move the Suburban for street cleaning this am and it started right, but this is what he found after the short move from the street to the driveway:

42FAE081-61FE-4FCF-9819-6E66E61BD96B.jpeg1C23402D-0B3B-414C-BF62-ACCFB5D6AF0A.jpeg

I told him to go through and replace the fuel line from the hard line to the FFM. I had replaced the line from the lift pump to the hard line.
 
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