A quick question RE: 460 PI engine

Discussion in 'General Automotive Questions' started by handy_andy_cv64, Apr 25, 2017.

  1. Hillbilly

    Hillbilly In Maximum Overdrive

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    The lower end of the rod has a keyed slot it goes in then rotates so a tang holds it in place. The top end uses a small spring from the throttle solenoid bracket and hooks thru a tiny hole in the top end of the connecting rod.
     
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  2. handy_andy_cv64

    handy_andy_cv64 In Maximum Overdrive SILVER MEMBER

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    Crap. Neither carb has a throttle solenoid. I've seen a few 4300s for sale, I think one, maybe two, had one. Thank you.
     
  3. Hillbilly

    Hillbilly In Maximum Overdrive

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    Make a little tab to go under the carb mounting nut in that corner for your lower spring holder. Then find a little weak spring to fit thru the tiny hole in the top of the rod. Put a little washer behind the spring top to keep the rocker arm from rubbing thru the spring.
     
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  4. handy_andy_cv64

    handy_andy_cv64 In Maximum Overdrive SILVER MEMBER

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    I think I know what you mean. I'll give it a try.
     
  5. handy_andy_cv64

    handy_andy_cv64 In Maximum Overdrive SILVER MEMBER

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    So I was able to score a throttle solenoid, which attached right up, and one of the connectors in the engine harness is correct for the solenoid, so the carb (the wagon's one) must've had one, and it has a spring that looks a bit different from the kickdown lever spring, so I assume it must've gone to the accel pump rod. Anyway, the rod on that has a boogered lower end, the tab's gone. So I pulled the rod off the PI carb, and installed it. However, it was bent in places it shouldn't have been, so the pump arm wouldn't work. It wouldn't even hold the pump's fulcrum arm correctly.

    PSX_20201217_145550.jpg PSX_20201217_145614.jpg PSX_20201217_145637.jpg

    So this morning, I bent the rod back to resemble the old rod:

    PSX_20201217_150023.jpg

    The PI carb's rod's on the left; I'm now going to install it. Hopefully it'll do the job and not be a problem I barely have any expertise to tackle. Yes, I don't normally mess around with carbs.
     
  6. handy_andy_cv64

    handy_andy_cv64 In Maximum Overdrive SILVER MEMBER

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    So it's installed:

    PSX_20201217_154908.jpg PSX_20201217_154936.jpg

    First is at rest. I have not measured the plunger height yet. Second is the WOT position, and the plunger and arm are bottomed out. So, when I adjust it, the manual says, for '68 and newer, to bend the rod; I know you bend at the bends, not the straight sections, but do you bend both, to keep the ends vertical? Or will it still properly actuate with only one one of the bends bent?
     
  7. handy_andy_cv64

    handy_andy_cv64 In Maximum Overdrive SILVER MEMBER

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    Well, I simply jumped in, bent the rod at both elbows; the spec for the non-police 4300D calls for 15/32" height at closed throttle. So, throttle closed, and throttle at WOT:

    PSX_20201217_164914.jpg PSX_20201217_164945.jpg

    I just need to hook up choke t-stat power and verify butterfly opening spec, and plug all unused vacuum ports. Then exhaust manifolds, plugs, wires and cap, and some gas into the float bowl, then hook up a battery and hope she fires.
     
  8. Hillbilly

    Hillbilly In Maximum Overdrive

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    Yeah, the ends need to be on the same plane to prevent binding. Plunger height looks a little low, that leaves you with less pump shot and you might need more. I see someone moved the fulcrum arm pivot pin out of the middle hole in the past. Probably trying to compensate for a worn plunger rubber. The design of the plunger bore is tapered toward the top of the bore so if the plunger is too high you get a delayed squirt until the plunger rubber reaches the straight part of the pump bore. Ford didn't give you much room to work with on the plunger travel especially considering the pump is only activated on the first part of the throttle movement. Every dang one of these carbs seem to be a little different so you probably don't want to hear this part. Remove the carb and place it on the bench using blocks that let the throttle blades have full travel. Next fill the carb with fuel then visually find how high you can set the plunger looking for the spot where the plunger rubber gets into the taper of the pump bore. When you find the height where the pump consistently produces a nice fat squirt, bend the rod to match that height at the idle position of the throttle blades. A weak accelerator pump shot is one of the flaws common to these carbs. A healthy pump shot stops stumbling and bogging at initial throttle tip in then the power valve takes over and supplies the needed extra fuel. If the power valve is stuck or gunked up, you will have a huge bog when the secondarys start to open. It must be clean and free to move. Put a new filter on there too, the less dirt that goes in that carb, the better.
     
  9. Hillbilly

    Hillbilly In Maximum Overdrive

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    That looks much better. Try it ! You may still have to finness it but you are in the ballpark .
     
  10. handy_andy_cv64

    handy_andy_cv64 In Maximum Overdrive SILVER MEMBER

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    Thank you! I was hoping you'd chime in. The carb rebuild kit sheet specified the 15/64ths for the non-PI carb, and it looks like I'm within 1/64" high. We bought the kit for the airhorn gasket, but I went ahead and replaced the accel pump cup and a couple other parts. The needle and seat were new when Joe first got the car, so I left it, but I can replace it if needed. I just hope there aren't any other problems. But, of course, once we fire it off, I'll post how it went. Oh, one more question: the 'A' Vin exhaust doesn't match the 'C' VIN manifolds, and the Bear's old exhaust was trash from the manifolds back. Will we have to cover the manifold ends against fresh air on the exhaust valves? I figure you'll know, as you deal with race cars of all stripes.
     
  11. Hillbilly

    Hillbilly In Maximum Overdrive

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    Depends a lot on the temperature ( ambient ) at the time you fire it off. 50 degrees or above should be ok. Remember this, the longer the engine runs the more heat is stored in the surrounding metal giving you a safety net of sorts. If I know you, there will be a few healthy blips of the throttle involved if nothing else just to listen to the big boy breathing. ALWAYS let it return to idle for at least 30 seconds to let things equalize heat wise before you kill the ignition. Good idea to have an observer on both sides because there will be a healthy flame front several inches past the manifold outlets. Don't have flammable junk under the car.
    Gonna' be loud ! Hope the neighbors are understanding too. Don't expect it to idle smoothly, you can work on that after the exhaust is in place.
     
  12. handy_andy_cv64

    handy_andy_cv64 In Maximum Overdrive SILVER MEMBER

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    Got it. Yeah, the Bear was lapping flame when we fired up the 351, but as soon as I dialed in the initial timing, they just about went away. Good to know on the ambient temp, this is South Texas, and so far, the late Fall's been warmer than normal. So I figure, as long as the carb's not lean, and I get the dwell and timing set toot-sweet, it should warm up nicely without warming up too fast when cold.
     
  13. handy_andy_cv64

    handy_andy_cv64 In Maximum Overdrive SILVER MEMBER

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    So it's been about 2 1/2 months since posting. Put a gallon of water in, the lowest tube immediately leaked. Pulled that radiator, popped in the wagon's radiator, no leaks so far. Had to tighten the lower hose clamp at the water pump because it began dribbling as I added another gallon of water. Don't worry about the straight water; we put in a de-rusting compound. I swear, it looks like it has black strap molasses in it. Anyway, got the negative cable hooked up, plopped the Bear's battery in it, and just to make sure it wouldn't start leaking oil anywhere, we cranked it with the coil disconnected and no plugs. Smooth with good speed on the starter motor.
     
  14. Hillbilly

    Hillbilly In Maximum Overdrive

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    I use EvapoRust. Scary what comes out of engines even the ones with clean antifreeze. Keep rinsing afterwards, eventually the rinse will be clean.
     
  15. handy_andy_cv64

    handy_andy_cv64 In Maximum Overdrive SILVER MEMBER

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    I've heard of it, but we've already put this in. The heavy rinse-out is really necessary, though, no matter what you use. This'll get a flush tee when the time comes.
     
  16. Hillbilly

    Hillbilly In Maximum Overdrive

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    Have had to remove the block drains on a few to get all the crud out. Caught some of the crud and examined it to find most of it was casting sand and nearly dissolved casting mold support wires. On the ones I could easily reach I knocked out the rearmost freeze plugs only to find crud built up as high as the top of the freeze plugs. Engines seemed to run much cooler with all that junk out.
     
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  17. handy_andy_cv64

    handy_andy_cv64 In Maximum Overdrive SILVER MEMBER

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    Oddly enough, I had that on a Jeep 4.0L six. Low miles, owner loved it but it would run hot all the time, and she loved it too much to trade it in. Well, it sprang a leak at the rear freeze plug, so, yard out the drivetrain and remove the flexplate. When I popped the old plug out, wet sand began to ooze out. I showed the boss, he said dig it out. I complied, got soaked flushing the block out and dragging the rest of the caked sand from the coolant jacket. What a mess. But. once back together and burped, it finally ran where it was supposed to, temperature-wise. Oh, and this was a Chrysler Jeep, not an AMC Jeep.
     
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  18. Hillbilly

    Hillbilly In Maximum Overdrive

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    Failure to wash out the casting sand has plagued every brand. I think the most notorious was the case of the 6.0 liter International diesels sold to Ford. Do you know the story on howcome that came about Andy ?
     
  19. handy_andy_cv64

    handy_andy_cv64 In Maximum Overdrive SILVER MEMBER

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    :DI do now.....
     
  20. handy_andy_cv64

    handy_andy_cv64 In Maximum Overdrive SILVER MEMBER

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    I had only heard what were rumor and supposition, but you confirmed a couple of them (Ford wanting to dump Navistar, and the head bolts not to design spec). The casting sand, I figured was just one or two that got past QA, but if it was a lot more, yikes.
     

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