Replaced Carb, Can't Get Truck to Start (3 Viewers)

[sp73]

My new to me truck's carb needed a rebuild and I picked up a working one that was pulled when a fellow member went with a different setup.

Install went well, I have double and in some cases triple checked everything. Truck turns over, will not start. The carb glass reads full and I disconnected the fuel line to the carb to confirm fuel was pumping. Using carb cleaner, the engine fires immediately and heads to redline briefly.

New fuel filter, fresh gas. Truck was previously starting easy enough.

That's it.

 

[John McVicker]

Did you accidentally pull off the dizzy wire or similar?

 

[sp73]

No clue what that is?

 

[John McVicker]

The wire to the distributor on the engine.

 

[sp73]

No I didn’t touch anything on the ignition side.

 

[John McVicker]

You most likely have something installed incorrectly or missing in your rebuilt carb. And your carb glass should not read ‘full’, it should read 1/2 full on the glass.

 

[sp73]

You most likely have something installed incorrectly or missing in your rebuilt carb. And your carb glass should not read ‘full’, it should read 1/2 full on the glass.

Yeah if I put gas directly in the carb it starts immediately but revs towards redline.

 

[mattressking]

Yeah if I put gas directly in the carb it starts immediately but revs towards redline.

If it starts when you dump fuel in primary barrel, your accelerator pump is not functioning or ICS is not connected/non-responsive, or bad emissions computer. First, remove intake, rotate butterfly from closed to full open and verify fuel is/is not squirting a solid stream of fuel from barrel closest to valve cover.

If that is working correctly then disconnect fuel cut solenoid wire from chassis harness, ground the white and provide 12v direct from battery to the other wire (orientation doesn't truly matter here for testing). Make sure you hear a distinct click from solenoid on carburetor.

Report back after on both.

 

[sp73]

If it starts when you dump fuel in primary barrel, your accelerator pump is not functioning or ICS is not connected/non-responsive, or bad emissions computer. First, remove intake, rotate butterfly from closed to full open and verify fuel is/is not squirting a solid stream of fuel from barrel closest to valve cover.

If that is working correctly then disconnect fuel cut solenoid wire from chassis harness, ground the white and provide 12v direct from battery to the other wire (orientation doesn't truly matter here for testing). Make sure you hear a distinct click from solenoid on carburetor.

Report back after on both.

Fuel is not squirting from the barrel, if I did as you said correctly. I’m pumping the accelerator rod by hand and looking down the barrel.

 

[mattressking]

Fuel is not squirting from the barrel, if I did as you said correctly. I’m pumping the accelerator rod by hand and looking down the barrel.

Another way to verify is look-in in barrel and have somoene press the throttle completely to the floor to ensure you're doing it correctly. If thats the case and no fuel is squirting then.....

1. AP nozzle is clogged
2. AP pin circuit is clogged or incorrect spring/pin
3. Accelerator Pump or spring is damaged or missing spring.

All of which will need carb disassembled to inspect properly.

 

[DrRock]

Hello All, @sp73 has my old carb from my 1985 FJ60. When I pulled it from my truck, it worked really well. It has been sitting a while but when I pulled it I ran it dry. Just wanted to chime in here so I can help out and so that all know what the carb’s vintage is.

Let me know how I can help.

Cheers, James

 

[sp73]

Another way to verify is look-in in barrel and have somoene press the throttle completely to the floor to ensure you're doing it correctly. If thats the case and no fuel is squirting then.....

1. AP nozzle is clogged
2. AP pin circuit is clogged or incorrect spring/pin
3. Accelerator Pump or spring is damaged or missing spring.

All of which will need carb disassembled to inspect properly.

The bellows on the AP is missing the top which probably does nothing. The spring is very slow to respond when I push down the arm attached to it vs. my old carb.

 

[mattressking]

Cool - double check the fuel cut solenoid clicks reliably - if it does - I’d recommend removing and servicing carburetor

 

[sp73]

If it starts when you dump fuel in primary barrel, your accelerator pump is not functioning or ICS is not connected/non-responsive, or bad emissions computer. First, remove intake, rotate butterfly from closed to full open and verify fuel is/is not squirting a solid stream of fuel from barrel closest to valve cover.

If that is working correctly then disconnect fuel cut solenoid wire from chassis harness, ground the white and provide 12v direct from battery to the other wire (orientation doesn't truly matter here for testing). Make sure you hear a distinct click from solenoid on carburetor.

Report back after on both.

Solenoid test is good. Audible clicking.

 

[sp73]

Progress has been made.

Last night I noticed that the plate which bolts on top of the carb that the accelerator rod linkage hooks to was under the base of the carb and not on top. My mistake - this cased noticeable gap. I installed it correctly and tightened the four carb bolts sealing the gap between the carb base and the engine.

The engine will start with the choke out, and will stay running if I lightly feather the pedal. It quits with the choke off.

 

[John McVicker]

The easiest/best thing I can suggest is for you to access the series of 2f carb rebuild videos by PinHead.

They are GREAT videos by PinHead who is a long time Mud member. Very easy to follow videos that will get you back on track.

Sorry I don’t have the link.

 

[sp73]

The easiest/best thing I can suggest is for you to access the series of 2f carb rebuilds by PinHead.

They are GREAT videos by PinHead who is a long time Mud member. Very easy to follow videos that will get you back on track.

Sorry I don’t have the link.

I saw the link last night. I’ll find it - thanks.

 

[DrRock]

How long did you let the engine warm up for prior to taking off the choke? I used to let the temp needle creep up 1/4 before.

 

[sp73]

We are up and running gents.

Choke OUT --> Idle around 1100 and smooth
Choke IN --> Idle rough and around 500. Engine stalls after it gets fully warmed up.

I'm looking at the FSM right now for idle issues.