Accelerator Pump Discharge Weight Spring (1 Viewer)

[RustyAndDusty]

I disassembled the carb on my ‘85 fj60 and the discharge weight didn’t have a spring under it. The check ball is there but no spring to be found. I figured I’d look around my junk drawers for a spring that fits but wanted to double check with you guys if there might be a good reason to reassemble it without the spring. I assume some previous owner lost it when doing a rebuild. What kind of symptoms could a missing spring cause? Thanks!

 

[OSS]

I recall other people using a ball point pen spring with good success.

Or if you wanted to get fancier, remove a ball point pen spring from the pen then search online for a comparable dimensioned stainless steel spring. Try McMaster Carr.

 

[RustyAndDusty]

I recall other people using a ball point pen spring with good success.

Or if you wanted to get fancier, remove a ball point pen spring from the pen then search online for a comparable dimensioned stainless steel spring. Try McMaster Carr.

Great idea, pen spring it is!

 

[RustyAndDusty]

I recall other people using a ball point pen spring with good success.

Or if you wanted to get fancier, remove a ball point pen spring from the pen then search online for a comparable dimensioned stainless steel spring. Try McMaster Carr.

The pen spring worked great, thanks. I did trim it down a bit as it was pushing the weight up with more force than I imagine it needed. Carb is back on the truck and running although only with the choke pulled as I didn't measure how many turns it took to remove the idle mixture screw when I cleaned it. I turned it out 1-1/2 turns as pinhead suggests in his carb rebuild video. Guessing I'll need to turn it out a bit more to richen the mixture a bit in order to get it to idle without the choke so I can warm it up and attempt the whole lean drop idle adjustment process.

 

[RustyAndDusty]

Actually, upon further inspection Im not sure its really mixture issue Im having. My accelerator pump isn't squirting fuel into the carb after the rebuild. It just kind of dribbles out now. I disconnected the linkage to the actuator arm and operated it by hand and the pump sprays fuel with force but the range in which it sprays it outside of the upward limits that the linkage can reach. Maybe I made a mistake somewhere with my linkages? I checked with a diagram and it seems good but if anyone can find something obvious in this photo of mine please let me know!

 

[RustyAndDusty]

Sorry, I got that wrong, double checked and the linkage does reach far enough but the plunger doesn't go down quick enough/easily enough to spray the fuel like when I do it by hand. The rod reaches the top but the arm follows slowly behind by the pressure of the spring if that makes sense. Here's a photo I snapped immediately after pulling the throttle and the spring allows the actuator arm to take its time reaching the top. Not sure what the issue could be here. Is the accelerator pump plunger that came with my kit a little too snug or did I get something wrong here when rebuilding? If I keep pumping it til there's no more fuel to for the pump to spray it sprays out air fast and east, there's no resistance.

 

[OSS]

Maybe the aftermarket accelerator pump piston is too tight in the bore.
If you’ve got your old worn pump piston, reinstall that and see if the actuation is smoother. If so…. That new piston is a bit too chubby.

 

[RustyAndDusty]

I went ahead and threw the original accelerator pump back in and it has the same problem now as the new one. Im thinking its not the pump. My next theory is that I pushed the retaining clip that goes under the accelerator pump too far and its holding the check ball down and not allowing the fuel to come through that port with enough volume. Does that actually make sense or is that no how that system works? Either way seems like I need to open this thing up again.

 

[RustyAndDusty]

I went ahead and threw the original accelerator pump back in and it has the same problem now as the new one. Im thinking its not the pump. My next theory is that I pushed the retaining clip that goes under the accelerator pump too far and its holding the check ball down and not allowing the fuel to come through that port with enough volume. Does that actually make sense or is that no how that system works? Either way seems like I need to open this thing up again.

I’m going to take the air horn off the carb again today but I had a realization just now. My carb kit came with two different gaskets for the air horn. I used the one seen on the left i this screenshot. Is that my mistake? Should I put the other one as seen on the right side in there?

 

[RustyAndDusty]

It was the makeshift accelerator pump discharge weight spring… I removed it and the pump works great now so… not really sure what the purpose of that spring is but I’m back on track. Judging by all the posts I see on here where people find out their weight is stuck or even dimpled in place by a previous owner it seems the spring is unnecessary.

 

[jaymorgan]

It’s been a few months, is it still running strong without the spring? I’m having the same issue and thinking I need to take the makeshift spring out of there too now.

 

[RustyAndDusty]

It’s been a few months, is it still running strong without the spring? I’m having the same issue and thinking I need to take the makeshift spring out of there too now.

Yep, works perfectly without a spring in there. I say ditch it if you're having the same exact problem I was.

 

[jaymorgan]

Yep, works perfectly without a spring in there. I say ditch it if you're having the same exact problem I was.

Awesome. Thank you.