Okay, the next question is: Since I didn't put that rod back in, would that either cause it to never hit 3rd? I am playing with the old one right now...If I push on the rod, I feel a spring. I assume the vacuum on this line pulls the modulator in and the pin comes with it? In that case, I can see where the pin missing would keep it from shifting into third. However, I have read where people shorten those pins and their shift points are stacked....so confused and tired of smelling like ATF.

 

I can't answer that. I *think* it would not allow the trans to shift into 3rd.

 

simple enough to put it back on. It was my initial understanding that a bad mod would not allow the truck out of 1st gear, but that is definitely not the case with my vehicle.

 

I still don't know if the missing pin would prevent the trans from shifting into 3rd.

Now that I've rested a bit, I can say that the vacuum pulls the valve internals back, making the pin seat further into the valve, when there is high manifold vacuum (idle/light throttle and cruising). When the engine load increases due to throttle being opened further, the manifold vacuum drops. This would push the pin back into the trans.
The harder you are accelerating, the later the shift points *should* be. Without the pin, the trans be seeing a false signal of no load, which *should* make the shift points lower.


I do know that after I replaced my mod valve after it removed itself, my trans no longer shifted into 2nd in 10 feet, or into 3rd at 25MPH max.
A couple years later I had the trans rebuilt, and the tech drove the truck, then used a small flat blade screwdriver to adjust the valve (inside the vac fitting) in order to delay the shifts even more, as it still wanted to shift into 2nd at 5-10MPH unless I was really on throttle.

 

Okay, another few discoveries:

1) The carb has one nut missing. The back left nut was sitting on the left valve cover. When I put it on, It ran down and stopped 1/4 of an inch from the carb base. I looked and the threads stop there. Do I just add a few washers to the bottom of the nut to get it to snug down? I know I have a leak back there because if I spray carb cleaner back there, the engine about stalls out.

2) I figured out how to make the shift indicator sit on the PRND21 properly. However, my shift collar only allows 5 positions as is (PRND2). How do I adjust the shift collar?

3) I made my first venture to a junk yard. I found a replacement horn bar and ***** for the light and wiper switch. Tomorrow, I will go back and get the instrument bezel as mine is rosewood and my radio bezel is black. I am beginning to really see signs of where this truck was cobbled together.

4) Same yard has a good C6 transmission for sale. They want $100 for it. Should I screw with my old one or replace it with the one in the yard?

Thanks in advance for your opinions and advice!

 

Washers between the nut and carb should help secure the carb, however, I'd suggest pulling the carb and checking the base gasket.

I don't know on the shift collar, and I didn't see any question in the third point.

$100 for a C6 isn't bad, if it comes with a warrentty. Certainly less than a rebuild or even a carry-out rebuilt unit.

 

One should always put a flat washer between aluminum and nuts or bolts ... Preferably a hardened one, never a locking one.

Yes, it's ok to add enough flat washers to prevent the nut from bottoming out on the stud, however if you pull the carb try and screw the stud in a little deeper if possible.

-Enjoy
fh : )_~

 

Shorter studs should be pretty cheap at an auto parts store, I suspect the EGR valve has been
removed and that's why this situation is occurring. If I were taking it apart for some reason
(maybe to replace the gaskets) I'd prolly replace the studs with shorter ones, too.

 

So these things are just studs that screw into the intake manifold? Can I just double-nut them and run them back down into the manifold? I'm just trying to see if the missing bolt would stop the vacuum leak.

 

I just went back to page 1 and looked at your pics again, I see your EGR valve there so I'm
not sure why you're having the problem of not enough threads on the studs, maybe they
can be screwed into the manifold some more (yes, that's what these are) or maybe somebody
replaced 'em with ones that are too long or somethin;'.

In any event, yeah, you can use washers and/or double-nutting or whatever you need to hold
the carb firmly in place to stop the vacuum leaks. if it were mine, I'd investigate why this
situation exists and fix it correctly the next time I were to be taking it apart for some reason.

 

Is it possible the goober who took the nut off (must have removed the carb for whatever reason) ended up backing out the stud if then nut was frozen on it? I can see if the nut was locked on tight, he could have unscrewed the stud from the manifold and made it "longer" in a way.

 

I found that the front right one is longer than the other two as well. but at least it is snugged down on the carb.

 

I have an idea, i'd like more opinions if you guys are giving them away:

Late C-6 Valve Body: eBay Motors (item 370123818106 end time Jul-25-10 08:57:22 PDT)

Is that a good deal? He said he would replace the VB if it does not work. $25 seems like a steal. Plus, if I put it in and the old one just needs rebuilt, I'll throw a shiftkit in that one and wait for a rainy day to do some tinkering.

If the VB isn't bad, and I have reverse gear (which I do), does that ONLY leave the governor as the culprit? No strange noises or anything come from the transmission and the fluid was bright red. I am really not wanting to take it to a tranny shop only to have them tell me they want to rebuild it...but I guess that maybe the case.

I have checked vacuum at the VM
I have replaced the VM
I have adjusted the lever linkages

Short of opening the transmission and dropping the VB, I don't know what else to do.

 

Could be, I don't see why not. But, this seems to be the least of your problems.

I don't know much about auto trannies so I can't help there, you passed my level of
knowledge long ago....

-ct

 

Okay, I got a tach at the yard for $8. I got it installed and just took it down the road.

At idle, I am at 1000 RPM. I engage R or D and the idle drops to 900. I watch the tach as I drive and see it shift into 2nd at 1100-1200 RPM. In 2nd, I get to 2000 at 45MPH. At this point, the engine is howling. When I coast, I can feel the engine slowing the truck down.

I never see it go to 3rd.

I ordered that VB. I will put it in as soon as I get it.

I love junkyards.