lugnutgmc
Well-known member
This is for an AHU motor swapped into an 81 Caddy. The motor was running about a year ago in the swap, then I had a valve stick and had to pull the motor to rebuild it and the head. I reinstalled it in the last week, but have not been able to get it started. It cranks great, but I don't think I'm getting any fuel into the cylinders. No smoke or even a hint of starting.
This is an ALH pump swapped into an AHU.
So far we've done the following:
Primed the pump and filter multiple times with a mitghty vac, also pressurized the tank, we had good fuel out of the lines, both feed and return.
Cranked the engine with the injectors cracked and all we get are dribbles of fuel and air bubbles.
Replaced the 109 relay
Checked wiring
Replaced the shut off solenoid with a used known good one
I then thought the seals on the pump might be bad from sitting, although there are no visible leaks. So we started replacing the seals, the old ones seem suspect, so I'm hoping that was the cause of the air in the system.
While we had the pump apart I realized the fuel adjustment collar was sticking, I'm used to them moving freely, this one was almost stuck to the shaft, I had to manual free it up. Then I tried manual cycling the quantity adjuster in the top of the pump, it would barely move. I have another old pump pulled apart and the springs cause it to snap back, this one at first was stuck in position and after sea foam now resets slowly but does not move easily.
Any suggestions for freeing this up? I think to disassemble the pump further to clean the shaft I need to desolder the connections, something I'm not sure I want to do.
There were also some fine metal filings stuck to the top cover of the pump. Not a good sign
This is an ALH pump swapped into an AHU.
So far we've done the following:
Primed the pump and filter multiple times with a mitghty vac, also pressurized the tank, we had good fuel out of the lines, both feed and return.
Cranked the engine with the injectors cracked and all we get are dribbles of fuel and air bubbles.
Replaced the 109 relay
Checked wiring
Replaced the shut off solenoid with a used known good one
I then thought the seals on the pump might be bad from sitting, although there are no visible leaks. So we started replacing the seals, the old ones seem suspect, so I'm hoping that was the cause of the air in the system.
While we had the pump apart I realized the fuel adjustment collar was sticking, I'm used to them moving freely, this one was almost stuck to the shaft, I had to manual free it up. Then I tried manual cycling the quantity adjuster in the top of the pump, it would barely move. I have another old pump pulled apart and the springs cause it to snap back, this one at first was stuck in position and after sea foam now resets slowly but does not move easily.
Any suggestions for freeing this up? I think to disassemble the pump further to clean the shaft I need to desolder the connections, something I'm not sure I want to do.
There were also some fine metal filings stuck to the top cover of the pump. Not a good sign