Is this AVK Vacuum Actuator Change-over bad? (pics)

[sinful7]

Third post in about a week- that means one thing: Stuff's broken! Thanks to all the replies on my previous posts. I honestly didn't expect to find this, but in replacing my thermostat, I pulled the PS pump and the vacuum actuator for the intake change over mechanism. What I found inside was a spring that had been broken into four smaller springs, and lots of gunk on the changeover cylinder. The vacuum actuators and the arms are in fine shape, so I'm wondering if I can just replace the little spring between the actuator and the runner cylinder, but the plastic engagement notches on these parts look suspect. What do you think?





Thanks again for all the help.

[diagnosticator]

Replace that part with a new or good used part,

[sinful7]

I've ordered a new one from ECS, I think this one looks destroyed.

- - - Updated - - -

Thanks! Will do.

[sinful7]

So I received and installed the new part- Here's the pics. One thing that happened to me is the plastic bushing at the far end of the intake manifold became dislodged, falling into the lower intake runners. I removed the IM and shook it out, and here's what I noticed:
First, here's a comparison of the old changeover cylinder and the new one. Notice the new one has a bisecting channel:


Next, the far side bushing, on which I replaced the isolating O-rings with 10mmx14mm Dorman rings:




This bushing goes on the end of the changeover:



And on installation, I had to lubricate the changeover actuator o-ring (at the valve side of the changeover) as well as the receiving intake manifold flange with motor oil to get it to fit. I probably removed/reinstalled it a dozen times to get it to seat without too much force. I couldn't imagine doing this with the IM installed - it took pressure and gentle wiggling to get it to seat completely. the end result is the changeover and the intake manifold ports should align perfectly:




Last thing to note is that the replacement part is one piece. One $400 piece. Be gentle with it. The plastic circumferential bushings could be broken or dislodge easily if you use excessive force, but when you get down to seating and sealing the piece, the o-ring requires a gentle, persistent rocking to get it in place. Just take your time and if it doesn't feel right, work it back out and try again.
Thank you for the help Diagnosticator!

[diagnosticator]

Good job! (the 10mm X 14mm O rings look a bit to fat however. A thinner cross section O ring would fit better, and be easier to assemble.)

That part was a lot more expensive than I would have guessed. :>(

[Zach L]

Thanks for sharing all this detailed info. Props for taking the care and time to get it done the right way

[sinful7]

Good job! (the 10mm X 14mm O rings look a bit to fat however. A thinner cross section O ring would fit better, and be easier to assemble.)

That part was a lot more expensive than I would have guessed. :>(

I agree about the thinner o-ring, but the way those were worn it looked as if the bushing had been spinning in the receiving orifice, so I assumed they used to be much larger. that end seated without much trouble, but I will note that the crossover is not quite as easy to manipulate as previously. It doesn't bind however, so I attribute that to new vacuum actuator springs and diaphragms. The end bushing did become seated fully without trouble, reaching in through the throttle body hole to position.